diff --git a/.circleci/config.yml b/.circleci/config.yml
index c6a2acb950..08bc03f609 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -17,13 +17,17 @@ jobs:
     parameters:
       XCODE_VER:
         type: string
-        default: "12.5.1"
+        # https://circleci.com/docs/using-macos/#supported-xcode-versions-silicon
+        default: "13.4.1"
       CC:
         type: string
         default: "" # e.g. "clang"
       CXX:
         type: string
         default: "" # e.g. "clang++"
+      CPP:
+        type: string
+        default: "" # e.g. "clang -E"
       CC_STDVER:
         type: string
         default: "" # e.g. "-std=gnu17"
@@ -39,15 +43,27 @@ jobs:
       BREW_MORE:
         type: string
         default: "" # e.g. "avahi" for all-driver tests
+      #HOMEBREW_PREFIX:
+        # Detected below at run-time
+        # See https://docs.brew.sh/Installation :
+        # * /opt/homebrew for Apple Silicon,
+        # * /usr/local for macOS Intel and
+        # * /home/linuxbrew/.linuxbrew for Linux
+        # TODO: Find a way to select one of the values based on the platform?
+        #type: string
+        #default: "/opt/homebrew" # since July 2024 CircleCI only serves Apple Silicon instances
+        #default: "/usr/local" # was when CircleCI builders had x86
 
     environment:
       CC: << parameters.CC >>
       CXX: << parameters.CXX >>
+      CPP: << parameters.CPP >>
       CC_STDVER: << parameters.CC_STDVER >>
       CXX_STDVER: << parameters.CXX_STDVER >>
       BUILD_TYPE: << parameters.BUILD_TYPE >>
       CI_BUILDDIR: << parameters.CI_BUILDDIR >>
       BREW_MORE: << parameters.BREW_MORE >>
+      #HOMEBREW_PREFIX: << parameters.HOMEBREW_PREFIX >>
 
     # Specify the execution environment. You can specify an image from Dockerhub or use one of our Convenience Images from CircleCI's Developer Hub.
     # See: https://circleci.com/docs/2.0/configuration-reference/#docker-machine-macos-windows-executor
@@ -65,25 +81,63 @@ jobs:
 
       # Note: MacOS default /bin/bash 3.x is too old for ci_build.sh
       # Brew brings /usr/local/bin/bash 5.x as of this writing
-      # TODO: Are Binutils needed?
+      # We also reinstall/relink openssl@3 because asciidoc deps pull
+      # in openssl@1 and MAYBE they conflict (cause lack of exposed
+      # symlinks).
       - run:
           name: "homebrew"
           command: |-
-            HOMEBREW_NO_AUTO_UPDATE=1; export HOMEBREW_NO_AUTO_UPDATE;
-            brew install ccache bash libtool pkg-config gd libusb neon net-snmp openssl $BREW_MORE #binutils
+            #HOMEBREW_NO_AUTO_UPDATE=1; export HOMEBREW_NO_AUTO_UPDATE;
+            brew install ccache bash libtool binutils autoconf automake git m4 \
+                pkg-config aspell asciidoc docbook-xsl cppunit gd \
+                libusb neon net-snmp \
+                nss openssl \
+                libmodbus freeipmi powerman $BREW_MORE
+            #brew reinstall openssl@3
+            if ps -ef | grep -v grep | grep sshd ; then
+                brew install mc
+                ifconfig -a || true
+            fi
 
-#      - run:
-#          name: "homebrew-libtool"
-#          command: |-
-#            #find /usr /opt /lib* -name '*ltdl*' -ls 2>/dev/null || true
-#            brew unlink libtool && brew link libtool
-#            #find /usr /opt /lib* -name '*ltdl*' -ls 2>/dev/null || true
+      # https://github.com/Homebrew/legacy-homebrew/issues/15488
+      - run:
+          name: "homebrew-relink"
+          command: |-
+            #find /usr /opt /lib* -name '*ltdl*' -ls 2>/dev/null || true
+            brew unlink libtool && brew link libtool
+            #find /usr /opt /lib* -name '*ltdl*' -ls 2>/dev/null || true
+            brew info openssl
+            #brew info openssl@3
+            #brew info openssl@1.1
+            #command -v pkg-config || true
+            #pkg-config --list-all || true
+            #HOMEBREW_PREFIX="`brew config | grep HOMEBREW_PREFIX: | awk '{print $2}'`"
+            #ls -la "${HOMEBREW_PREFIX}/lib/pkgconfig" || true
+            #ls -la "${HOMEBREW_PREFIX}/include/openssl" || true
+            #ls -la "${HOMEBREW_PREFIX}/include/openssl"/* || true
+            #find "${HOMEBREW_PREFIX}"/Cellar/openssl* -ls || true
+            pkg-config --libs --cflags nss
+            pkg-config --libs --cflags openssl || {
+                brew unlink openssl && brew link --force openssl
+                pkg-config --libs --cflags openssl ; }
+            brew unlink net-snmp && brew link --force net-snmp
 
       - restore_cache:
           keys:
             - ccache-{{ .Branch }}-{{ arch }}-{{ .Environment.CIRCLE_JOB }}
             - ccache-master-{{ arch }}-{{ .Environment.CIRCLE_JOB }}
 
+      # Fail fast if we had a problem with prerequisites - this
+      # situation would likely impact all build branches anyway.
+      # Requires a Personal API token in the building account:
+      # https://support.circleci.com/hc/en-us/articles/360052058811-Exit-Build-Early-if-Any-Test-Fails
+      - run:
+          name: Fail Fast
+          when: on_fail
+          command: |-
+            echo "Canceling workflow as a step resulted in failure"
+            curl -X POST --header "Content-Type: application/json" "https://circleci.com/api/v2/workflow/${CIRCLE_WORKFLOW_ID}/cancel?circle-token=${CIRCLE_TOKEN}"
+
 #      - run:
 #          name: "check shell"
 #          command: /usr/bin/env bash --version || true; command -v bash || true
@@ -99,14 +153,16 @@ jobs:
       # uses of sem_init() and sem_destroy() in nut-scanner.c)
       # NOTE: CANBUILD_NIT_TESTS=yes to check if single-executor environments
       # do not have a problem with it.
+      # NOTE: python3.11 is available but broken on some of the workers
+      # (no homebrew dirs in search path)
       - run:
           name: "ci_build"
           command: |-
-            CI_CCACHE_SYMLINKDIR="/usr/local/opt/ccache/libexec" \
+            HOMEBREW_PREFIX="`brew config | grep HOMEBREW_PREFIX: | awk '{print $2}'`" \
             CANBUILD_NIT_TESTS=yes \
-            CFLAGS="$CC_STDVER -Wno-poison-system-directories -Wno-deprecated-declarations" \
-            CXXFLAGS="$CXX_STDVER -Wno-poison-system-directories" \
-            LDFLAGS="-L/usr/local/lib" \
+            CFLAGS="$CC_STDVER" \
+            CXXFLAGS="$CXX_STDVER" \
+            PYTHON=python3.12 \
             ./ci_build.sh
 
       - run:
@@ -125,6 +181,13 @@ jobs:
             - ~/.ccache
           key: ccache-{{ .Branch }}-{{ arch }}-{{ .Environment.CIRCLE_JOB }}
 
+      - store_artifacts:
+          path: config.log
+
+      - store_artifacts:
+          path: config.nut_report_feature.log
+
+
 # Invoke jobs via workflows
 # See: https://circleci.com/docs/2.0/configuration-reference/#workflows
 workflows:
@@ -132,37 +195,58 @@ workflows:
     jobs:
       # Note: while "ccache" lists hordes of symlinks to gcc-XXX versions,
       # in practice these toolkits are not installed (by default)
+      # or actually identify as clang
 
 ### This scenario is a subset of fightwarn-all below (modulo C standard),
 ### so disabled to not waste time from free CircleCI allowance limit:
 #      - osx-xcode:
-#          name: "gnu17-clang-xcode12_5_1-default-all-errors"
-#          XCODE_VER: "12.5.1"
+#          name: "gnu17-clang-xcode13_4_1-default-all-errors"
+#          XCODE_VER: "13.4.1"
 #          CC: "clang"
 #          CXX: "clang++"
 #          CC_STDVER: "-std=gnu17"
 #          CXX_STDVER: "-std=gnu++17"
 
+#      - osx-xcode:
+#          name: "gnu11-gcc-xcode13_4_1-out-of-tree"
+#          CC: "gcc"
+#          CXX: "g++"
+#          CC_STDVER: "-std=gnu11"
+#          CXX_STDVER: "-std=gnu++11"
+#          # Try an out-of-tree build:
+#          CI_BUILDDIR: "obj"
+
+#      - osx-xcode:
+#          name: "c99-cxx11-gcc-xcode13_4_1-default-distcheck"
+#          CC: "gcc"
+#          CXX: "g++"
+#          CC_STDVER: "-std=c99"
+#          CXX_STDVER: "-std=c++11"
+#          # Try usual and distchecked build:
+#          BUILD_TYPE: "default"
+
       - osx-xcode:
-          name: "gnu11-gcc-xcode12_5_1-out-of-tree"
-          CC: "gcc"
-          CXX: "g++"
+          name: "gnu11-clang-xcode13_4_1-out-of-tree"
+          CC: "clang"
+          CXX: "clang++"
+          CPP: "clang -E"
           CC_STDVER: "-std=gnu11"
           CXX_STDVER: "-std=gnu++11"
           # Try an out-of-tree build:
           CI_BUILDDIR: "obj"
 
       - osx-xcode:
-          name: "c99-cxx11-gcc-xcode12_5_1-default-distcheck"
-          CC: "gcc"
-          CXX: "g++"
+          name: "c99-cxx11-clang-xcode13_4_1-default-distcheck"
+          CC: "clang"
+          CXX: "clang++"
+          CPP: "clang -E"
           CC_STDVER: "-std=c99"
           CXX_STDVER: "-std=c++11"
           # Try usual and distchecked build:
           BUILD_TYPE: "default"
 
       - osx-xcode:
-          name: "stdDefault-xcode12_5_1-fightwarn-all"
+          name: "stdDefault-xcode13_4_1-fightwarn-all"
           # Run "default-all-errors" with both compiler families,
           # using their default C/C++ standard for current release:
           BUILD_TYPE: "fightwarn-all"
@@ -170,8 +254,8 @@ workflows:
 ### This does not work due to missing dependencies built for MacOS in homebrew:
 ### TODO? Evaluate other packagers (MacPorts, fink...)?
 #      - osx-xcode:
-#          name: "c17-clang-xcode12_5_1-alldrv"
-#          XCODE_VER: "12.5.1"
+#          name: "c17-clang-xcode13_4_1-alldrv"
+#          XCODE_VER: "13.4.1"
 #          CC: "clang"
 #          CXX: "clang++"
 #          CC_STDVER: "-std=c17"
diff --git a/.github/codeql/codeql-config.yml b/.github/codeql/codeql-config.yml
new file mode 100644
index 0000000000..28eaa5d8a1
--- /dev/null
+++ b/.github/codeql/codeql-config.yml
@@ -0,0 +1,4 @@
+# For interpreted languages:
+paths:
+  - scripts/python/module
+  - scripts/python/app
diff --git a/.github/workflows/PyNUTClient.yml b/.github/workflows/PyNUTClient.yml
index 018562485b..e4a4834180 100644
--- a/.github/workflows/PyNUTClient.yml
+++ b/.github/workflows/PyNUTClient.yml
@@ -47,7 +47,7 @@ jobs:
             {  TAG_NAME="$(git describe --tags --match 'v[0-9]*.[0-9]*.[0-9]' --exclude '*-signed' --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*')" \
             || TAG_NAME="$(git describe --tags --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*' --exclude '*Windows*' --exclude '*IPM*')" ; } \
             && test -n "${TAG_NAME}" \
-            || TAG_NAME="2.8.1-`TZ=UTC date +%s`" ;
+            || TAG_NAME="2.8.2-`TZ=UTC date +%s`" ;
         fi >&2 ;
         TAG_NAME="$(echo "$TAG_NAME" | sed -e 's/^v\([0-9]\)/\1/' -e 's,^.*/,,' -e 's/^v//' -e 's/-g.*$//' -e 's/-/./g')" ;
         echo "TAG_NAME=$TAG_NAME" >> $GITHUB_OUTPUT
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 2438bd0555..edb55bd86f 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -23,7 +23,7 @@ on:
 jobs:
   analyze:
     name: Analyze
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     permissions:
       actions: read
       contents: read
@@ -32,10 +32,22 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
+        # https://docs.github.com/en/actions/using-jobs/using-a-matrix-for-your-jobs
         language: [ 'cpp' ]
         # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
         # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
-        # TODO: Want to find Python sources to test like with LGTM, see https://github.com/networkupstools/nut/issues/1726
+        os: ['ubuntu-latest']
+        # TOTHINK: windows-latest, macos-latest
+        compiler: ['CC=gcc CXX=g++', 'CC=clang CXX=clang++']
+        NUT_SSL_VARIANTS: ['no', 'nss', 'openssl']
+        NUT_USB_VARIANTS: ['no', 'libusb-1.0', 'libusb-0.1']
+        include:
+          # Add cell(s) to the matrix, beside the combinatorics made above
+          - language: 'python'
+            os: 'ubuntu-latest'
+            compiler: 'PYTHON=python3'
+            NUT_SSL_VARIANTS: 'no'
+            NUT_USB_VARIANTS: 'no'
 
     steps:
     - name: Checkout repository
@@ -52,12 +64,40 @@ jobs:
 
         # Details on CodeQL's query packs refer to : https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
         # queries: security-extended,security-and-quality
+        config-file: ./.github/codeql/codeql-config.yml
 
+    # https://docs.github.com/en/code-security/code-scanning/creating-an-advanced-setup-for-code-scanning/codeql-code-scanning-for-compiled-languages
+    - if: matrix.language == 'cpp' && matrix.os == 'ubuntu-latest'
+      name: NUT CI Prerequisite packages (Ubuntu)
+      run: |
+        sudo apt update
+        case x"${{matrix.compiler}}" in x*clang*) sudo apt install clang ;; x*) sudo apt install gcc g++ ;; esac
+        sudo apt install libltdl-dev libtool libtool-bin cppcheck ccache libgd-dev libcppunit-dev libsystemd-dev libssl-dev libnss3-dev augeas-tools libaugeas-dev augeas-lenses libusb-dev libusb-1.0-0-dev libmodbus-dev libsnmp-dev libpowerman0-dev libfreeipmi-dev libipmimonitoring-dev libavahi-common-dev libavahi-core-dev libavahi-client-dev libgpiod-dev libneon27-dev libi2c-dev i2c-tools lm-sensors
 
     # Autobuild attempts to build any compiled languages  (C/C++, C#, Go, or Java).
     # If this step fails, then you should remove it and run the build manually (see below)
-    - name: Autobuild
-      uses: github/codeql-action/autobuild@v3
+    #- name: Autobuild
+    #  uses: github/codeql-action/autobuild@v3
+
+    #- if: matrix.language == 'cpp'
+    #  name: NUT CI Build (default-all-errors matrix)
+    #  run: |
+    #    BUILD_TYPE=default-all-errors BUILD_SSL_ONCE=true DO_DISTCHECK=no CI_SKIP_CHECK=true CANBUILD_DOCS_ALL=no ${{ matrix.compiler }} NUT_SSL_VARIANTS=${{ matrix.NUT_SSL_VARIANTS }} NUT_USB_VARIANTS=${{ matrix.NUT_USB_VARIANTS }} ./ci_build.sh
+
+    #- if: matrix.language == 'cpp'
+    #  name: NUT CI Build (fightwarn-all)
+    #  run: |
+    #    BUILD_TYPE=fightwarn-all ./ci_build.sh
+
+    # TOTHINK: Can we prepare the working area once (apt, autogen => containers?)
+    # and then spread it out for builds and analyses?
+    # Can ccache be used across builds?
+    - if: matrix.language == 'cpp'
+      name: NUT CI Build
+      run: |
+        ./autogen.sh
+        ./configure --enable-warnings --enable-Werror --enable-Wcolor --with-all=auto --with-dev --without-docs ${{matrix.compiler}} --with-ssl=${{matrix.NUT_SSL_VARIANTS}} --with-usb=${{matrix.NUT_USB_VARIANTS}}
+        make -s -j 8
 
     # ℹ️ Command-line programs to run using the OS shell.
     # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
diff --git a/.gitignore b/.gitignore
index bc2e70a1a3..fd04ce4e58 100644
--- a/.gitignore
+++ b/.gitignore
@@ -14,6 +14,7 @@
 /_install_pkgprotodir/
 Makefile
 Makefile.in
+
 ## Parent directory only
 /aclocal.m4
 /ar-lib
@@ -22,6 +23,7 @@ Makefile.in
 /ChangeLog.adoc
 /config.guess
 /config.log
+/config.log.inplace-outer
 /config.status
 /config.sub
 /config.h
@@ -43,16 +45,23 @@ Makefile.in
 /README
 /TODO
 /UPGRADING
+/VERSION_DEFAULT
+/VERSION_FORCED
+/VERSION_FORCED_SEMVER
 /install-sh
 /libtool
 /ltmain.sh
 /missing
 /test-driver
+*-contentchecked
 *-spellchecked
 *-prepped
+*.usage-report
 *.adoc-parsed
 *.adoc*.tmp
+*.adoc*.tmp.*
 *.txt*.tmp
+*.txt*.tmp.*
 /cppcheck*.xml
 /.ci*.txt*
 /.ci*.log
diff --git a/COPYING b/COPYING
index 94adc8c31f..40882612c2 100644
--- a/COPYING
+++ b/COPYING
@@ -3,7 +3,14 @@
  or (at your option) any later version. See "LICENSE-GPL2" in the root of this
  distribution.
 
- The files in the scripts/python/ directory are released under GNU General
+ The scripts/python/module/nut_telnetlib.py file is copied for fall-back
+ purposes from Python 3.10, and released under its original license (the
+ PSF License Version 2). It was only modified in the comment section to
+ describe the copy, purpose and provenance per section 3 of the license.
+ According to https://github.com/python/cpython/blob/3.10/LICENSE most of
+ the licenses Python was provided under over the years are GPL-compatible.
+
+ Other files in the scripts/python/ directory are released under GNU General
  Public License (GPL) version 3, or (at your option) any later version. See
  "LICENSE-GPL3" in the root of this distribution.
 
@@ -11,6 +18,11 @@
  license as Perl itself. That is to say either GPL version 1 or (at your option)
  any later version, or the "Artistic License".
 
+ The scripts/installer contents were donated to the Network UPS Tools project
+ by Eaton in 2022, including the license change from the one originally used
+ with their software companion to terms of the open-source project (that is,
+ GPL version 2 or newer).
+
  Several fallback implementations for methods absent from standard library of
  an end-user's current build platform are derived from source code available
  under the two-clause BSD license (common/strptime.c, common/strnlen.c)
diff --git a/Jenkinsfile-dynamatrix b/Jenkinsfile-dynamatrix
index 11e14f15bf..e55a526ddd 100644
--- a/Jenkinsfile-dynamatrix
+++ b/Jenkinsfile-dynamatrix
@@ -25,7 +25,8 @@ import org.nut.dynamatrix.*;
     def dynacfgPipeline = [:]
 
     // NOTE: These can be further disabled or active in different combo specs
-    // below based on branch names
+    // below based on branch names. Also note that the values are somewhat
+    // "inversed" -- e.g. that "disabledSomething = false" means "enable it".
     dynacfgPipeline.disableSlowBuildAutotools = false
     dynacfgPipeline.disableSlowBuildCIBuild = false
     dynacfgPipeline.disableSlowBuildCIBuildExperimental = false
@@ -254,7 +255,7 @@ import org.nut.dynamatrix.*;
 
     // Imported from jenkins-dynamatrix JSL vars/autotools.groovy:
     // a workaround for the cases of curiously missing MAKE envvar...
-    dynacfgPipeline.buildPhases['distcheck'] = """( if [ x"\${MAKE-}" = x ]; then echo "WARNING: MAKE is somehow unset, defaulting!" >&2; MAKE=make; fi; eval \${CONFIG_ENVVARS} time \${MAKE} \${MAKE_OPTS} distcheck DISTCHECK_FLAGS="\${CONFIG_OPTS}" )"""
+    dynacfgPipeline.buildPhases['distcheck'] = """( if [ x"\${MAKE-}" = x ]; then echo "WARNING: MAKE is somehow unset, defaulting!" >&2; MAKE=make; fi; eval \${CONFIG_ENVVARS} time \${MAKE} \${MAKE_OPTS} distcheck DISTCHECK_FLAGS=\${CONFIG_OPTS:+\\"\$CONFIG_OPTS\\"} )"""
 
     // Note: shellcheck/spellcheck/... require autotools currently
     // or need to be redefined with respective BUILD_TYPE
@@ -285,7 +286,10 @@ set | sort -n """
         }
 
         withEnvOptional(dynacfgPipeline.defaultTools) {
-            unstashCleanSrc(dynacfgPipeline.stashnameSrc)
+            stage('Unstash sources') {
+                unstashCleanSrc(dynacfgPipeline.stashnameSrc)
+            }
+
             buildMatrixCellCI(dynacfgPipeline, dsbcClone, stageNameClone)
             //buildMatrixCellCI(dynacfgPipeline, dsbc, stageName)
         }
@@ -315,7 +319,10 @@ set | sort -n """
         }
 
         withEnvOptional(dynacfgPipeline.defaultTools) {
-            unstashCleanSrc(dynacfgPipeline.stashnameSrc)
+            stage('Unstash sources') {
+                unstashCleanSrc(dynacfgPipeline.stashnameSrc)
+            }
+
             def dynacfgPipeline_ciBuild = dynacfgPipeline.clone()
             dynacfgPipeline_ciBuild.buildSystem = 'ci_build.sh'
             dynacfgPipeline_ciBuild.buildPhases = [:]
@@ -421,6 +428,64 @@ set | sort -n """
         //'bodyParStages': {}
         ] // one slowBuild filter configuration, autotools-Wall
 
+        ,[name: 'Default autotools driven build with default configuration, bitness and warning levels on each NUT CI farm platform (but with fatal warnings as of gnu99/gnu++11, must pass where enabled)',
+         disabled: dynacfgPipeline.disableSlowBuildAutotools,
+         //branchRegexSource: ~/^(PR-.+|fightwarn.*)$/,
+         //branchRegexTarget: dynacfgPipeline.branchStableRegex,
+         //branchRegexTarget: ~/fightwarn/,
+         //appliesToChangedFilesRegex: dynacfgPipeline.appliesToChangedFilesRegex_C,
+         'getParStages': { def dynamatrix, Closure body ->
+            return dynamatrix.generateBuild([
+                //commonLabelExpr: dynacfgBase.commonLabelExpr,
+                //defaultDynamatrixConfig: dynacfgBase.defaultDynamatrixConfig,
+                requiredNodelabels: [],
+                excludedNodelabels: [],
+
+                dynamatrixAxesVirtualLabelsMap: [
+                    //'BITS': [32, 64],
+                    // 'CSTDVERSION': ['03', '2a'],
+                    //'CSTDVERSION_${KEY}': [ ['c': '03', 'cxx': '03'], ['c': '99', 'cxx': '98'], ['c': '17', 'cxx': '2a'], 'ansi' ],
+                    //'CSTDVERSION_${KEY}': [ ['c': '03', 'cxx': '03'], ['c': '99', 'cxx': '98'], ['c': '17', 'cxx': '2a'] ],
+                    'CSTDVERSION_${KEY}': [ ['c': '99', 'cxx': '11'] ],
+                    'CSTDVARIANT': ['gnu']
+                    ],
+                dynamatrixAxesCommonEnv: [
+                    // One set of several simultaneously exported envvars!
+                    // CONFIG_OPTS are picked up by our dynamatrix configuration
+                    // and substituted into shell "as is" for normal builds
+                    // (so splitting into many tokens), or quoted as a single
+                    // token DISTCHECK_FLAGS in its stage (split by make later).
+                    ['LANG=C','LC_ALL=C','TZ=UTC',
+                     'CONFIG_OPTS=--with-all=auto --with-docs=auto --with-ssl=auto --enable-Werror --enable-warnings --disable-Wcolor --enable-silent-rules'
+                    ]
+                    ],
+
+                mergeMode: [ 'dynamatrixAxesVirtualLabelsMap': 'replace', 'excludeCombos': 'merge' ],
+                allowedFailure: [
+                    dynacfgPipeline.axisCombos_WINDOWS,
+                    dynacfgPipeline.axisCombos_STRICT_C
+                    ],
+                runAllowedFailure: true,
+                //dynamatrixAxesLabels: ['OS_FAMILY', 'OS_DISTRO', '${COMPILER}VER', 'ARCH${ARCH_BITS}'],
+                //dynamatrixAxesLabels: [~/^OS/, '${COMPILER}VER', 'ARCH${ARCH_BITS}'],
+                dynamatrixAxesLabels: [~/^OS_DISTRO/, 'COMPILER'],
+                excludeCombos: dynacfgPipeline.excludeCombos_DEFAULT_STRICT_C
+                    + [dynacfgPipeline.axisCombos_WINDOWS_CROSS]
+                    + [[~/OS_DISTRO=openbsd-6\./, ~/COMPILER=GCC/]]
+                    // Here we picked just OSes and compilers (gcc or clang),
+                    // so exclude systems which have e.g. gcc-4.2.1 which claims
+                    // type range comparison warnings despite pragma fencing.
+                    // gcc-4.8.x on CentOS 7 and Ubuntu 14.04 looks already okay.
+                    + [[~/OS_DISTRO=macos/]]
+                    // MacOS (at least agents prepared with HomeBrew packages)
+                    // requires a few pkg-config and CFLAGS pre-sets which are
+                    // done in ci_build.sh and defeat the purpose of this stage.
+                    // So it is easier and more honest to just skip it.
+                ], body)
+            }, // getParStages
+        //'bodyParStages': {}
+        ] // one slowBuild filter configuration, autotools-everywhere
+
         ,[name: 'Various non-docs distchecked target builds with main and ~newest supported C/C++ revisions (must pass on all platforms)',
          disabled: dynacfgPipeline.disableSlowBuildCIBuild,
          //branchRegexSource: ~/^(PR-.+|fightwarn.*)$/,
@@ -478,8 +543,8 @@ set | sort -n """
                     // BUILD_TYPE=default-tgt:distcheck-light + NO_PKG_CONFIG=true ?
                     ],
                 dynamatrixAxesCommonEnv: [
-                    ['LANG=C','LC_ALL=C','TZ=UTC'
-                     //,'BUILD_WARNFATAL=yes','BUILD_WARNOPT=hard'
+                    ['LANG=C','LC_ALL=C','TZ=UTC','BUILD_WARNFATAL=yes'
+                     //,'BUILD_WARNOPT=hard'
                     ]
                     ],
                 allowedFailure: [
@@ -527,8 +592,8 @@ set | sort -n """
                     'BUILD_TYPE': ['default-tgt:cppcheck']
                     ],
                 dynamatrixAxesCommonEnv: [
-                    ['LANG=C','LC_ALL=C','TZ=UTC', 'DO_CLEAN_CHECK=no'
-                     //,'BUILD_WARNFATAL=yes','BUILD_WARNOPT=hard'
+                    ['LANG=C','LC_ALL=C','TZ=UTC', 'DO_CLEAN_CHECK=no', 'BUILD_WARNFATAL=yes'
+                     //,'BUILD_WARNOPT=hard'
                     ]
                     ],
                 allowedFailure: [
@@ -685,7 +750,8 @@ set | sort -n """
                     ],
                 dynamatrixAxesCommonEnv: [
                     ['LANG=C','LC_ALL=C','TZ=UTC',
-                     'BUILD_WARNFATAL=yes','BUILD_WARNOPT=minimal'
+                     'BUILD_WARNFATAL=yes'
+                     //,'BUILD_WARNOPT=medium'
                     ]
                     ],
                 allowedFailure: [
@@ -726,9 +792,14 @@ set | sort -n """
                 dynamatrixAxesCommonEnv: [
                     ['LANG=C','LC_ALL=C','TZ=UTC',
                      // Build in a subdirectory to check that out-of-dir
-                     // builds are healthy too
+                     // builds are healthy too.
+                     // NOTE: It would be useful to also have a recipe to build
+                     // "completely out-of-tree", in a different filesystem (to
+                     // make sure we do not rely on hard-links, relative paths,
+                     // etc.)
                      'CI_BUILDDIR=obj',
-                     'BUILD_WARNFATAL=yes','BUILD_WARNOPT=minimal'
+                     'BUILD_WARNFATAL=yes'
+                     //,'BUILD_WARNOPT=minimal'
                     ]
                     ],
                 allowedFailure: [
@@ -767,7 +838,8 @@ set | sort -n """
                     ],
                 dynamatrixAxesCommonEnv: [
                     ['LANG=C','LC_ALL=C','TZ=UTC',
-                     'BUILD_WARNFATAL=yes','BUILD_WARNOPT=minimal'
+                     'BUILD_WARNFATAL=yes'
+                     //,'BUILD_WARNOPT=minimal'
                     ]
                     ],
                 allowedFailure: [
@@ -1213,7 +1285,7 @@ set | sort -n """
         'bodyParStages': dynacfgPipeline.slowBuildDefaultBody_ci_build
         ] // one slowBuild filter configuration
 
-        ,[name: 'Strict C and GNU standard builds on cross-Windows platforms (Linux+mingw), without distcheck and docs (allowed to fail)',
+        ,[name: (dynacfgPipeline.disableStrictCIBuild_CrossWindows ? '' : 'Strict C and ') + 'GNU standard builds on cross-Windows platforms (Linux+mingw), without distcheck and docs (allowed to fail)',
          disabled: dynacfgPipeline.disableSlowBuildCIBuild,
          //branchRegexSource: ~/^(PR-.+|.*fightwarn.*|.*Windows.*)$/,
          //branchRegexTarget: ~/fightwarn|Windows-.*/,
diff --git a/Makefile.am b/Makefile.am
index bac4f8eb2b..2a108bdda8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -3,11 +3,21 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
+
+# First target often defines default behavior: all
+# We follow up with another pass to `make doc` because our wild recipes
+# sometimes preclude generating all of them on the first pass (FIXME!)
+# missing e.g. PDF and HTML which then pop up in `make check` footprint,
+# or misses a .prep-src-docs stage needed to pattern-make man page files
+# with some "make" implementations...
+all all-am-local all-local: all-recursive
+	+@$(MAKE) $(AM_MAKEFLAGS) doc
+	+@$(MAKE) $(AM_MAKEFLAGS) doc
 
 # include directory for aclocal
 ACLOCAL_AMFLAGS = -I m4
@@ -60,6 +70,7 @@ endif
 
 DISTCHECK_FLAGS = --with-all --with-ssl --with-doc=auto --with-pynut=app --with-nut_monitor=force
 DISTCHECK_LIGHT_FLAGS = --with-all=auto --with-ssl=auto --with-doc=auto --with-pynut=app --with-nut_monitor=force
+DISTCHECK_LIGHT_MAN_FLAGS = --with-all=auto --with-ssl=auto --with-doc=man --with-pynut=app --with-nut_monitor=force
 DISTCHECK_VALGRIND_FLAGS = --with-all=auto --with-ssl=auto --with-doc=skip --with-valgrind CXXFLAGS='$(CXXFLAGS) -g' CFLAGS='$(CFLAGS) -g' --with-pynut=app --with-nut_monitor=force
 
 # Note: this rule uses envvar DISTCHECK_FLAGS expanded at run-time
@@ -73,12 +84,20 @@ DISTCHECK_CONFIGURE_FLAGS = ${DISTCHECK_FLAGS}		\
  --with-devd-dir='$${prefix}/etc/devd'			\
  --with-pynut=app --with-nut_monitor=force
 
+# Note: trickery with prefix below is needed to expand it from
+# DISTCHECK_CONFIGURE_FLAGS defaults defined above in a manner
+# that is meaningful for sub-make program (gets stripped away
+# otherwise and breaks custom distchecks).
 distcheck-light:
-	+$(MAKE) $(AM_MAKEFLAGS) DISTCHECK_FLAGS="$(DISTCHECK_LIGHT_FLAGS)" distcheck
+	+prefix='$${prefix}'; $(MAKE) $(AM_MAKEFLAGS) DISTCHECK_CONFIGURE_FLAGS="$(DISTCHECK_CONFIGURE_FLAGS)" DISTCHECK_FLAGS="$(DISTCHECK_LIGHT_FLAGS)" distcheck
+
+distcheck-light-man:
+	+prefix='$${prefix}'; $(MAKE) $(AM_MAKEFLAGS) DISTCHECK_CONFIGURE_FLAGS="$(DISTCHECK_CONFIGURE_FLAGS)" DISTCHECK_FLAGS="$(DISTCHECK_LIGHT_MAN_FLAGS)" distcheck
 
 # Make a distcheck (and check in particular) with enabled valgrind and debug info
 memcheck distcheck-valgrind:
-	+$(MAKE) $(AM_MAKEFLAGS) DISTCHECK_FLAGS="$(DISTCHECK_VALGRIND_FLAGS)" distcheck
+	@echo "See also scripts/valgrind in NUT sources for a helper tool"
+	+prefix='$${prefix}'; $(MAKE) $(AM_MAKEFLAGS) DISTCHECK_CONFIGURE_FLAGS="$(DISTCHECK_CONFIGURE_FLAGS)" DISTCHECK_FLAGS="$(DISTCHECK_VALGRIND_FLAGS)" distcheck
 
 # workaround the dist generated files that are also part of the distribution
 # Note that distcleancheck is disabled for now, while waiting for a proper
@@ -92,7 +111,7 @@ distcleancheck:
 realclean: maintainer-clean
 
 # Files made by our targets:
-CLEANFILES = *-spellchecked *.adoc-parsed cppcheck*.xml
+CLEANFILES = *-spellchecked *.adoc-parsed cppcheck*.xml config.log.inplace-outer
 DISTCLEANFILES = ChangeLog
 
 # Most of the files generated by custom rules in the configure script
@@ -141,7 +160,7 @@ distclean-local:
 spellcheck spellcheck-interactive:
 	+@RES=0; \
 	(cd $(builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) -s $(abs_top_builddir)/docs/.prep-src-docs) || RES=$$? ; \
-	(cd $(builddir)/docs/man && $(MAKE) $(AM_MAKEFLAGS) -s $(abs_top_builddir)/docs/.prep-src-docs) || RES=$$? ; \
+	(cd $(builddir)/docs/man && $(MAKE) $(AM_MAKEFLAGS) -s $(abs_top_builddir)/docs/man/.prep-src-docs) || RES=$$? ; \
 	(cd $(builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) -s $@) || RES=$$? ; \
 	(cd $(builddir)/docs/man && $(MAKE) $(AM_MAKEFLAGS) -s $@) || RES=$$? ; \
 	(cd $(builddir)/conf && $(MAKE) $(AM_MAKEFLAGS) -s $@) || RES=$$? ; \
@@ -165,13 +184,15 @@ spellcheck spellcheck-interactive:
 # such as PDF generators, so it should only be called at developer's
 # discretion, choice and risk. The "check-man" targets covers source
 # texts, man pages and HTML rendering of man pages, as enabled by tools.
-doc spellcheck-sortdict \
+doc spellcheck-sortdict spellcheck-report-dict-usage \
 all-docs check-docs \
-man all-man man-man check-man man-html all-html:
-	+cd $(builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) $@
+man all-man man-man check-man html-man all-html:
+	+cd $(abs_top_builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) -s $(abs_top_builddir)/docs/.prep-src-docs
+	+cd $(abs_top_builddir)/docs/man && $(MAKE) $(AM_MAKEFLAGS) -s $(abs_top_builddir)/docs/man/.prep-src-docs
+	+cd $(abs_top_builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) $@
 
 INSTALL.nut UPGRADING NEWS README:
-	+cd $(builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) ../$(@F).adoc-parsed && cp -f ../$(@F).adoc-parsed ../$(@F)
+	+cd $(abs_top_builddir)/docs && $(MAKE) $(AM_MAKEFLAGS) ../$(@F).adoc-parsed && cp -f ../$(@F).adoc-parsed ../$(@F)
 
 # Workarounds for https://github.com/github/markup/issues/1095
 # require direct definition of our attributes in each source
@@ -226,9 +247,29 @@ maintainer-asciidocs:
 	  fi; \
 	 )
 
-check-NIT check-NIT-devel:
+check-NIT check-NIT-devel check-NIT-sandbox check-NIT-sandbox-devel:
 	+cd $(builddir)/tests/NIT && $(MAKE) $(AM_MAKEFLAGS) $@
 
+VERSION_DEFAULT: dummy-stamp
+	@abs_top_srcdir='$(abs_top_srcdir)' ; \
+	 abs_top_builddir='$(abs_top_builddir)' ; \
+	 export abs_top_srcdir ; export abs_top_builddir ; \
+	 NUT_VERSION_QUERY=UPDATE_FILE '$(abs_top_srcdir)/tools/gitlog2version.sh'
+
+CLEANFILES += VERSION_DEFAULT.tmp
+EXTRA_DIST += VERSION_DEFAULT
+
+# Best-effort delivery for (overly?) customized distros, e.g. via
+#   echo NUT_VERSION_FORCED_SEMVER=1.1.1 > VERSION_FORCED_SEMVER
+dist-hook:
+	for D in "$(abs_top_srcdir)" "$(abs_top_builddir)" ; do \
+	    for F in VERSION_FORCED VERSION_FORCED_SEMVER ; do \
+	        if [ -s "$$D/$$F" ] ; then \
+	            cat "$$D/$$F" > "$(top_distdir)/$$F" || true ; \
+	        fi ; \
+	    done ; \
+	done
+
 # This target adds syntax-checking for committed shell script files,
 # to avoid surprises and delays in finding fatal typos after packaging
 ###
@@ -243,7 +284,7 @@ check-NIT check-NIT-devel:
 ###
 check-scripts-syntax:
 	@echo 'NOTE: modern bash complains about scripts using backticks (warning not error), which we ignore in NUT codebase for portability reasons: `...` obsolete, use $$(...)'
-	@RUNBASH=bash; if [ -x /bin/bash ]; then RUNBASH=/bin/bash ; else if [ -x /usr/bin/env ] ; then RUNBASH="/usr/bin/env bash"; fi; fi ; \
+	@RUNBASH=bash; if [ -x /bin/bash ] && /bin/bash -c 'echo $${BASH_VERSION}' | grep -E '^[456789]\.' ; then RUNBASH=/bin/bash ; else if [ -x /usr/bin/env ] ; then RUNBASH="/usr/bin/env bash"; fi; fi ; \
 	 for F in `git ls-files || find . -type f` ; do \
 	    case "`file "$$F"`" in \
 	        *"Bourne-Again shell script"*) ( set -x ; $$RUNBASH -n "$$F" ; ) ;; \
@@ -321,14 +362,62 @@ GITLOG_START_POINT=v2.6.0
 # the current dir, and defaults to generate a "ChangeLog" in the current dir.
 # The script itself is generated from a template, so resides in builddir.
 dummy-stamp:
-ChangeLog: tools/gitlog2changelog.py dummy-stamp
-	cd $(abs_top_srcdir) && \
+ChangeLog: dummy-stamp
+	+@$(MAKE) $(AM_MAKEFLAGS) $(abs_top_builddir)/ChangeLog
+
+if WITH_PDF_NONASCII_TITLES
+WITH_PDF_NONASCII_TITLES_ENVVAR = WITH_PDF_NONASCII_TITLES=yes
+else
+WITH_PDF_NONASCII_TITLES_ENVVAR = WITH_PDF_NONASCII_TITLES=no
+endif
+
+# Be sure to not confuse with a DIST'ed file (and so try to overwrite it);
+# do however avoid re-generating it if already made on a previous pass and
+# the Git HEAD pointer (branch) or its actual "index" or "object" database
+# did not change since then - meaning the local developer or CI did not
+# modify the metadata (subsequent generation of the huge PDF/HTML files
+# can cost dearly).
+# Note there's a bit more fuss about Git internals which NUT should not
+# really care about encapsulation-wise (detection of NUT_GITDIR location
+# which may reside elsewhere, e.g. with local repo clones with reference
+# repo configuration, or submodules). But this is a Git-crawling target
+# anyway, and in the worst case (Git's design changes) we would spend a
+# bit of time researching the FS in vain, and go on to re-generate the
+# ChangeLog when maybe we should not have - oh well.
+# WARNING: The CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR=true mode here is
+# default to allow for prettier documentation, but it can require too much
+# memory for weaker build systems. Set it to false when calling make there.
+CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR_ENVVAR = true
+$(abs_top_builddir)/ChangeLog: tools/gitlog2changelog.py dummy-stamp
+	@cd $(abs_top_srcdir) && \
 	    if test -e .git ; then \
-	        CHANGELOG_FILE="$@" $(abs_top_builddir)/tools/gitlog2changelog.py $(GITLOG_START_POINT) || \
-	        { printf "gitlog2changelog.py failed to generate the ChangeLog.\n\nNOTE: See https://github.com/networkupstools/nut/commits/master for change history.\n\n" > "$@" ; } ; \
+	        NUT_GITDIR=".git" ; if test -r "$${NUT_GITDIR}" -a ! -d "$${NUT_GITDIR}" ; then GD="`grep -E '^gitdir:' "$${NUT_GITDIR}" | sed 's/^gitdir: *//'`" && test -n "$$GD" -a -d "$$GD" && NUT_GITDIR="$$GD" ; fi ; \
+	        if test -s "$@" -a -d "$${NUT_GITDIR}" && test -z "`find "$${NUT_GITDIR}" -newer "$@" 2>/dev/null`" ; then \
+	            echo "  DOC-CHANGELOG-GENERATE        $@ : SKIP (keep existing)" ; \
+	            echo "Using still-valid ChangeLog file generated earlier from same revision of Git source metadata in '$${NUT_GITDIR}'" >&2 ; \
+	        else \
+	            echo "  DOC-CHANGELOG-GENERATE        $@" ; \
+	            CHANGELOG_FILE="$@" $(WITH_PDF_NONASCII_TITLES_ENVVAR) \
+	            CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR="$(CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR_ENVVAR)" \
+	              $(abs_top_builddir)/tools/gitlog2changelog.py $(GITLOG_START_POINT) || { \
+	                echo "  DOC-CHANGELOG-GENERATE        $@ : FAILED (non-fatal)" >&2 ; \
+	                printf "gitlog2changelog.py failed to generate the ChangeLog.\n\nNOTE: See https://github.com/networkupstools/nut/commits/master for change history.\n\n" > "$@" ; \
+	            } ; \
+	        fi ; \
 	    else \
-	        if ! test -s "$@" ; then \
-	            printf "Failed to generate the ChangeLog.\n\nNOTE: See https://github.com/networkupstools/nut/commits/master for change history.\n\n" > "$@" ; \
+	        if test x"$(abs_top_srcdir)" != x"$(abs_top_builddir)" -a -s ./ChangeLog ; then \
+	            echo "  DOC-CHANGELOG-GENERATE        $@ : SKIP (keep existing)" ; \
+	            echo "Using distributed ChangeLog file from sources" >&2 ; \
+	            rm -f "$@" || true ; \
+	            cat ./ChangeLog > "$@" ; \
+	        else \
+	            if test -s "$@" ; then \
+	                echo "  DOC-CHANGELOG-GENERATE        $@ : SKIP (keep existing)" ; \
+	                echo "Using distributed ChangeLog file from sources" >&2 ; \
+	            else \
+	                echo "  DOC-CHANGELOG-GENERATE        $@ : FAILED (non-fatal)" >&2 ; \
+	                printf "Failed to generate the ChangeLog.\n\nNOTE: See https://github.com/networkupstools/nut/commits/master for change history.\n\n" > "$@" ; \
+	            fi ; \
 	        fi ; \
 	    fi
 
@@ -393,7 +482,7 @@ install-dirs:
 	@echo "Warning: 'make install-dirs' is deprecated."
 	@echo "Use 'make installdirs' instead."
 	@echo $(WARN)
-	+$(MAKE) installdirs
+	+$(MAKE) $(AM_MAKEFLAGS) installdirs
 cgi build-cgi install-cgi install-cgi-dir install-cgi-bin \
 install-cgi-man install-cgi-conf install-cgi-html: 
 	@echo "Error: 'make $@' no longer exists."
@@ -460,7 +549,8 @@ if HAVE_WINDOWS
 # Then hardlink libraries for sbin... (alternative: all bins in one dir)
 # TOTHINK: Are there more dirs to consider? So far we cover bindir, sbindir and
 # driverexecdir (e.g. some Linux distros place drivers to /lib/nut while tools
-# and daemons are in /usr/bin and /usr/sbin), and cgiexecdir; anything else?..
+# and daemons are in /usr/bin and /usr/sbin), and cgiexecdir, and occasional
+# helpers like "sockdebug.exe" in libexecdir; anything else?..
 # Note we hold existance of cgiexecdir as optional, but the name is expected to
 # be defined. Other dirs are "just assumed" to exist (that we are not packaging
 # some NUT build without drivers/tools/daemons). Subject to change if needed.
@@ -486,7 +576,7 @@ install-win-bundle-thirdparty:
 	 (  cd '$(DESTDIR)' || exit ; \
 	    DESTDIR="" '$(abs_top_srcdir)/scripts/Windows/dllldd.sh' dllldddir . \
 	    | while read D ; do \
-	        echo "   DLL->bin   $$D" 2>&1 ; \
+	        echo "   DLL->bin       $$D" 2>&1 ; \
 	        cp -pf "$$D" './$(bindir)/' ; \
 	    done ; \
 	 ) || exit ; \
@@ -494,7 +584,7 @@ install-win-bundle-thirdparty:
 	    cd '$(DESTDIR)/$(sbindir)' || exit ; \
 	    '$(abs_top_srcdir)/scripts/Windows/dllldd.sh' dllldddir . \
 	    | while read D ; do \
-	        echo "   DLL->sbin  $$D" 2>&1 ; \
+	        echo "   DLL->sbin      $$D" 2>&1 ; \
 	        ln -f '$(DESTDIR)/$(bindir)'/"`basename "$$D"`" ./ ; \
 	    done ; \
 	 ) || exit ; \
@@ -503,7 +593,7 @@ install-win-bundle-thirdparty:
 	    cd '$(DESTDIR)/$(driverexecdir)' || exit ; \
 	    '$(abs_top_srcdir)/scripts/Windows/dllldd.sh' dllldddir . \
 	    | while read D ; do \
-	        echo "   DLL->drv   $$D" 2>&1 ; \
+	        echo "   DLL->drv       $$D" 2>&1 ; \
 	        ln -f '$(DESTDIR)/$(bindir)'/"`basename "$$D"`" ./ ; \
 	    done ; \
 	 ) || exit ; \
@@ -514,7 +604,18 @@ install-win-bundle-thirdparty:
 	    cd '$(DESTDIR)/$(cgiexecdir)' || exit ; \
 	    '$(abs_top_srcdir)/scripts/Windows/dllldd.sh' dllldddir . \
 	    | while read D ; do \
-	        echo "   DLL->cgi   $$D" 2>&1 ; \
+	        echo "   DLL->cgi       $$D" 2>&1 ; \
+	        ln -f '$(DESTDIR)/$(bindir)'/"`basename "$$D"`" ./ ; \
+	    done ; \
+	 ) || exit ; \
+	 (  if test x"$(libexecdir)" = x"$(bindir)" ; then exit 0 ; fi ; \
+	    if test x"$(libexecdir)" = x"$(sbindir)" ; then exit 0 ; fi ; \
+	    if test x"$(libexecdir)" = x"$(driverexecdir)" ; then exit 0 ; fi ; \
+	    if test x"$(libexecdir)" = x"$(cgiexecdir)" ; then exit 0 ; fi ; \
+	    cd '$(DESTDIR)/$(libexecdir)' || exit ; \
+	    '$(abs_top_srcdir)/scripts/Windows/dllldd.sh' dllldddir . \
+	    | while read D ; do \
+	        echo "   DLL->libexec   $$D" 2>&1 ; \
 	        ln -f '$(DESTDIR)/$(bindir)'/"`basename "$$D"`" ./ ; \
 	    done ; \
 	 ) || exit
@@ -523,9 +624,10 @@ install-win-bundle-thirdparty:
 	 relsbindir="`echo './$(sbindir)/' | sed 's,//*,/,g'`" ; \
 	 reldriverexecdir="`echo './$(driverexecdir)/' | sed 's,//*,/,g'`" ; \
 	 relcgiexecdir="`echo './$(cgiexecdir)/' | sed 's,//*,/,g'`" ; \
+	 rellibexecdir="`echo './$(libexecdir)/' | sed 's,//*,/,g'`" ; \
 	 cd '$(DESTDIR)' || exit ; \
 	 find . -type f | grep -Ei '\.(exe|dll)$$' \
-	 | grep -vE "^($${relbindir}|$${relsbindir}|$${reldriverexecdir}|$${relcgiexecdir})" \
+	 | grep -vE "^($${relbindir}|$${relsbindir}|$${reldriverexecdir}|$${relcgiexecdir}|$${rellibexecdir})" \
 	 | ( RES=0 ; while IFS= read LINE ; do echo "$$LINE" ; RES=1; done; exit $$RES )
 
 else
diff --git a/NEWS.adoc b/NEWS.adoc
index 10319c9cd2..f09a5c36c8 100644
--- a/NEWS.adoc
+++ b/NEWS.adoc
@@ -40,8 +40,337 @@ https://github.com/networkupstools/nut/milestone/11
  - (expected) Bug fixes for fallout possible due to "fightwarn" effort in 2.8.0
 
 
-PLANNED: Release notes for NUT 2.8.2 - what's new since 2.8.1
--------------------------------------------------------------
+ - Fix fallout of development in NUT v2.8.0 and/or v2.8.1 and/or v2.8.2:
+   * Move of `NUT_DEBUG_LEVEL` and "-D" CLI option handling to start of
+     driver programs for issue #2259 in NUT v2.8.2 release misfired with
+     regard to data-dump mode (it no longer caused foreground by default).
+     [#2408]
+   * The `nut-driver-enumerator.sh` improvements misfired in v2.8.2 release
+     with an overlooked bit of shell syntax, and caused `nut-driver@upsname`
+     instances to not auto-restart when `ups.conf` is edited. [#682, #2410]
+   * Addition of "NUT Simulated devices" support to `nut-scanner` in v2.8.2
+     broke detection of (in-)ability to find and query "Old NUT" servers via
+     `libupsclient.so` (internal flag got always enabled). [#2246]
+   * A fix for `upsmon` v2.8.1 setting of `OFFDURATION` [PR #2108, issue #2104,
+     revisiting PR #2055, issue #2044] was overly zealous and impacted also
+     the `OB` state in cases where communications to the data server were
+     severed and `DEADTIME` setting was not honored. [PR #2462, issue #2454]
+   * Using `drivername -c reload` (e.g. facilitated by `nut-driver-enumerator`
+     script and service when editing `ups.conf`) led to disconnected Unix
+     sockets and a tight polling loop that hogged CPU. While the underlying
+     bug is ancient, it took recent development to hit it as a practical
+     regression. [issue #1904, issue #2484]
+   * Fallback `localtime_r()` and `gmtime_r()` for some platform builds where
+     a `*_s()` variant was available was not handled correctly. [PR #2583]
+   * A recently introduced `allow_killpower` did not actually work as an
+     `ups.conf` flag (only as a protocol command). [issue #2605, PR #2606]
+
+ - development iterations of NUT should now identify with not only the semantic
+   version of a preceding release, but with git-derived information about the
+   amount of iterations that followed (if available): the three-number "semver"
+   would be seen on release snapshots, while other builds would expose the
+   added components: one with the amount of commits on the main development
+   trunk since the preceding release which are ancestors of the built code
+   base, and in case of feature development branches -- another component
+   with the amount of commits unique to this branch (which are not part of
+   the development trunk). This allows to produce more relevant (monotonously
+   growing) version identifiers for packages and similar artifacts, with more
+   meaningful upgrades via development snapshots, eventually. A copy of the
+   current version information would be embedded into "dist" archives as a
+   `VERSION_DEFAULT` file. [#1949]
+
+ - drivers, `upsd`, `upsmon`: reduce "scary noise" about failure to `fopen()`
+   the PID file (which most of the time means that no previous instance of
+   the daemon was running to potentially conflict with), especially useless
+   since in recent NUT releases the verdicts from `sendsignal*()` methods
+   are analyzed and lead to layman worded situation reports in these programs.
+   [issue #1782, PR #2384]
+
+ - drivers started with the `-FF` command-line option (e.g. wrapped into the
+   systemd units to stay "foregrounded" *and* save a PID file anyway) should
+   now also handle an existing PID file to interact with the earlier instance
+   of the driver program, if still running (e.g. started manually). [#2384]
+
+ - Extended instant commands for driver reloading with a `driver.exit`
+   command for a protocol equivalent of sending a `SIGTERM`, e.g. when
+   a newer instance of the driver program tries to start. [#1903, #2392]
+
+ - A new `NUT_QUIET_INIT_BANNER` envvar (presence or "true" value) can now
+   prevent the tool name and NUT version banner from being unilaterally
+   printed out when NUT programs start. [issues #1789 vs. #316; #2573]
+
+ - The `upsdrvctl` should now warn if executed on systems where NUT was
+   built with support for service management frameworks like systemd or SMF,
+   so nut-driver service units prepared by `nut-driver-enumerator` would
+   conflict with manually-executed driver programs. This warning can be
+   hushed by exporting a `NUT_QUIET_INIT_NDE_WARNING` environment variable
+   with any value.
+
+ - Extended `upsdrvctl` with a `list` operation (or `-l` option) to report
+   manageable device configuration names (possible `<ups>` arguments to
+   `start`, `stop` etc. operations), or to confirm a single name that it
+   is known, and a `status` operation for more information. [#2567]
+
+ - riello_ser updates:
+   * added `localcalculation` option to compute `battery.runtime` and
+     `battery.charge` if the device provides bogus values [issue #2390,
+     following in the footsteps of #1692, #1685 done for `riello_usb`]
+     (similar to `runtimecal` in some other drivers, may be refactored
+     to that configuration and logic model in later NUT releases)
+
+ - apcsmart updates:
+   * Revised code to use `strncpy()` and avoid potential overflows that are
+     possible with `strcpy()` used before. [PR #2564]
+   * Lost communications led to a logging flood, should not anymore.
+     In fact, the driver should try fully reconnecting upon getting into
+     a prolonged data stale condition. [issue #704, PR #2564]
+
+ - added Visench C1K (using serial port converter with USB ID `1a86:7523`)
+   as known supported by `nutdrv_qx` (Megatec protocol) since at least
+   NUT v2.7.4 release [#2395]
+
+ - bicker_ser: added new driver for Bicker 12/24Vdc UPS via RS-232 serial
+   communication protocol, which supports any UPS shipped with the PSZ-1053
+   extension module. [PR #2448]
+
+ - usbhid-ups updates:
+   * Support of the `onlinedischarge_log_throttle_hovercharge` in the NUT
+     v2.8.2 release was found to be incomplete. [#2423, follow-up to #2215]
+   * Added support for `lbrb_log_delay_sec=N` setting to delay propagation of
+     `LB` or `LB+RB` state (buggy with APC BXnnnnMI devices circa 2023-2024).
+     This may work better with flags like `onlinedischarge_calibration` and
+     `lbrb_log_delay_without_calibrating` for some devices. [#2347]
+   * General suggestion from `possibly_supported()` message method for devices
+     with VendorID=`0x06da` (Phoenixtec), seen in some models supported by
+     MGE HID or Liebert HID, updated to suggest trying `nutdrv_qx`. [#334]
+   * MGE HID list of `mge_model_names[]` was extended for Eaton 9E, 5PX and 5SC
+     series (largely guessing, feedback and PRs for adaptation to actual
+     string values reported by devices via USB are welcome), so these devices
+     would now report `battery.voltage` and `battery.voltage.nominal`. [#2380]
+   * `powercom-hid` subdriver sent UPS shutdown commands in wrong byte order,
+     at least for devices currently in the field. A toggle was added to set
+     the old behavior (if some devices do need it), while a fix is applied
+     by default: `powercom_sdcmd_byte_order_fallback`. [PR #2480]
+   * `cps-hid` subdriver now supports more variables, as available on e.g.
+     CP1350EPFCLCD model. [PR #2540]
+   * USB parameters (per `usb_communication_subdriver_t`) are now set back to
+     their default values during enumeration after probing each subdriver.
+     Having an unrelated device connected with a VID:PID matching the
+     `arduino-hid` subdriver prevented use of an actual `usb-hid` device due to
+     changes made to this struct during probe. [#2611]
+
+ - USB drivers could log `(nut_)libusb_get_string: Success` due to either
+   reading an empty string or getting a success code `0` from libusb.
+   This difference should now be better logged, and not into syslog. [#2399]
+
+ - USB drivers can benefit from a new `nut_usb_get_string()` method which
+   can do a fallback `en_US` query for devices which report a broken "langid"
+   language identifier value. This notably manifested in inability to query
+   device Manufacturer, Model and Serial Number values with some buggy device
+   firmware or hardware. [PR #2604, issues #1925, #414]
+   * Currently this was tested to fix certain device discovery with `usbhid-ups`;
+     should also apply out of the box to same discovery logic in `blazer_usb`,
+     `nutdrv_qx`, `riello_usb` and `tripplite_usb` drivers.
+   * Also applied to `nut-scanner` and `libnutscan`. [issue #2615]
+   * More work may be needed for other USB-capable drivers (`richcomm_usb`,
+     `nutdrv_atcl_usb`) and for general code to collect string readings and
+     other data points, and to configure the fallback locale or choose one
+     if several are served by the device. [issues #2613, #2614, #2615]
+
+ - USB drivers should now be more likely to succeed with iterative detection
+   of an UPS interface on a composite USB device or when looking at devices
+   with non-default interface/endpoint/config numbers. [PR #2611]
+
+ - Introduced a new driver concept for interaction with OS-reported hardware
+   monitoring readings. Currently instantiated as `hwmon_ina219` specifically
+   made for Texas Instruments INA219 chip as exposed in the Linux "hwmon"
+   subsystem of its "sysfs" interface (and talking I2C under the hood), this
+   approach seems to have good potential to expand into covering more devices
+   and perhaps platforms. [#2430]
+
+ - upsmon:
+   * it was realized that the `POWERDOWNFLAG` must be explicitly set in the
+     configuration file, there is no built-in default in the binary program
+     (the settings facilitated by the `configure` script during build "only"
+     impact the `upsmon.conf.sample`, init-scripts and similar files generated
+     from templates). [issue #321, PR #2383]
+   * added an `OBLBDURATION` (seconds) setting to optionally delay raising
+     the alarm for immediate shutdown in critical situation. [#321]
+
+ - More systemd integration:
+   * Introduced a `nut-sleep.service` unit which stops `nut.target` when a
+     system sleep was requested, and starts it when the sleep is finished.
+     This helps avoid NUT shutting down a woken-up system just because its
+     power state was critical before the sleep (called as a `SHUTDOWNCMD`
+     implementation by the end-user), and a next-read timestamp was not seen
+     (deemed to be a stale UPS, meaning lost communications during critical
+     state, so must go down ASAP). While not as elegant as native systemd
+     "inhibitor interface" support, this approach does work. [#1833, #1070]
+   * Introduced support for the "inhibitor interface" as well (should be
+     available on systems with systemd version 183 or newer) for a better
+     handling of the time jump specifically in the `upsmon` client via new
+     `Inhibit()` method in `common.c`. [#1070]
+   * As an extension of the logic introduced above, hopefully now `upsmon`
+     would behave better in face of any significant and unexpected clock
+     jumps (on POSIX builds so far), even if they are not suspend/hibernate
+     events (or they were but we could not have an inhibit lock). Now they
+     should be handled similar (avoid stale UPS data and rash decisions)
+     for summer/winter time change on non-UTC deployments, a debugger
+     suspending the `upsmon` process, etc. [#2597]
+
+ - gamatronic driver revised for safer memory operations; this was reported
+   to have fixed a Segmentation Fault seen in earlier NUT releases with
+   some of the devices supported by this driver. [#2427]
+
+ - upsd:
+   * `upsd_cleanup()` is now traced, to more easily see that the daemon is
+     exiting (and/or start-up has aborted due to configuration or run-time
+     issues). Warning about "world readable" files clarified. [#2417]
+
+ - nut-scanner:
+   * the tool relies on dynamic loading of shared objects (library files)
+     orchestrated at run-time rather than pre-compiled, to avoid excessively
+     huge package footprints. This however relies on knowing (or sufficiently
+     safely guessing) the library file names to use, and short `libname.so`
+     is not ubiquitously available. With the new `m4` macro `AX_REALPATH_LIB`
+     we can store and try to use the file name which was present on the build
+     system, while we search for a suitable library. [#2431]
++
+NOTE: A different but functionally equivalent trick is done for `libupsclient`
+during a NUT build.
+   * fixed support for IPv6 addresses (passed in square brackets) for both
+     `-s` start/`-e` end command-line options, and for `-m cidr/mask` option.
+     [issue #2512, PR #2518]
+   * newly added support to scan several IP addresses (single or ranges)
+     with the same call, by repeating command-line options; also `-m auto{,4,6}`
+     can be specified (once) to select IP (all, IPv4, IPv6) address ranges of
+     configured local network interfaces.
+     An `/ADDRLEN` suffix can be added to the option, to filter out discovered
+     subnets with too many bits available for the host address part (avoiding
+     millions of scans in the extreme cases).
+     [issue #2244, issue #2511, PR #2509, PR #2513, PR #2517]
+   * implemented parallel scanning for IPMI bus, otherwise default scan for
+     all supported buses with `-m auto` takes unbearably long. [#2523]
+   * bumped version of `libnutscan` to 2.6.0, it now includes a few more
+     methods and symbols from `libcommon`. [issue #2244, PR #2509]
+   * do not actively suggest `vendor(id)`, `product(id)`, and `serial` options
+     for `bcmxcp_usb`, `richcomm_usb` and `nutdrv_atcl_usb` drivers for now
+     [#1763, #1764, #1768, #2580]
+
+ - common code:
+   * introduced a `NUT_DEBUG_SYSLOG` environment variable to tweak activation
+     of syslog message emission (and related detachment of `stderr` when
+     backgrounding), primarily useful for NIT and perhaps systemd. Most
+     methods relied on logging bits being set, so this change aims to be
+     minimally invasive to impact setting of those bits (or not) in the
+     first place. [#2394]
+   * `root`-owned daemons now use not the hard-coded `PIDPATH` value set
+     by the `configure` script during build, but can override it with a
+     `NUT_PIDPATH` environment variable in certain use-cases (such as
+     tests). [#2407]
+   * introduced a check for daemons working with PID files to double-check
+     that if they can resolve the program name of a running process with
+     this identifier, that such name matches the current program (avoid
+     failures to start NUT daemons if PID files are on persistent storage,
+     and some unrelated program got that PID after a reboot).  This might
+     introduce regressions for heavily customized NUT builds (e.g. those
+     embedded in NAS or similar devices) where binary file names differ
+     significantly from a `progname` string defined in the respective NUT
+     source file, so a boolean `NUT_IGNORE_CHECKPROCNAME` environment
+     variable support was added to optionally disable this verification.
+     Also the NUT daemons should request to double-check against their
+     run-time process name (if it can be detected). [issue #2463]
+   * introduced `m4` macros to check during `configure` phase for the
+     platform, and a `nut_bool.h` header with `nut_bool_t` type to use
+     during build, to avoid the numerous definitions of Boolean types
+     and values (or macros) in the NUT codebase. [issue #1176, issue #31]
+   * custom `distcheck-something` targets did not inherit `DISTCHECK_FLAGS`
+     properly. [#2541]
+   * added `status_get()` in NUT driver state API, to check if a status
+     token string had been set recently, and to avoid duplicate settings.
+     [PR #2565]
+   * local socket/pipe protocol introduced a `LOGOUT` command for cleaner
+     disconnection handling. [#2572]
+   * codebase adapted to the liking of `clang-18` and newer revisions of
+     `gcc-13`+ whose static analyzers on NUT CI farm complained about some
+     imperfections after adding newer OS revisions to the population of
+     build agents. [#2585, #2588]
+
+ - updated `docs/nut-names.txt` with items defined by 42ITy NUT fork. [#2339]
+
+ - various recipe, documentation and source files were revised to address
+   respective warnings issued by the new generations of analysis tools.
+   [#823, #2437, link:https://github.com/networkupstools/nut-website/issues/52[nut-website issue #52]]
+
+ - added `scripts/valgrind` with a helper script and suppression file to
+   ignore common third-party problems. [#2511]
+
+ - revised `nut.exe` (the NUT for Windows wrapper for all-in-one service)
+   to be more helpful with command-line use (report that it failed to start
+   as a service, have a help message, pass debug verbosity to launched NUT
+   programs...) and add a man page for it. [issue #2432, PR #2446]
+
+ - the `PyNUTClient` module should no longer rely on presence of a `telnetlib`
+   module in the build or execution environment (deprecated in Python 3.11,
+   removed since Python 3.13). [#2183]
+
+ - enabled installation of built single-file PDF and HTML (including man page
+   renditions) under the configured `docdir`. It seems previously they were
+   only built (if requested) but not installed via `make`, unlike the common
+   man pages which are delivered automatically. [#2445]
++
+   NOTE: The `html-chunked` documents are currently still not installed.
+
+ - added support to `./configure --with-doc=man=dist-auto` to use distributed
+   manual page files if present; only fall back to build them if we can. [#2473]
+
+ - added a `make distcheck-light-man` recipe to require verification that the
+   manual page files can be built using the prepared "tarball" archive. [#2473]
+
+ - revised the documentation building recipes, with the goal to avoid building
+   the `ChangeLog` products and their intermediate files more than once (but
+   still react to `git` metadata changes during development), and to sanity
+   check the resulting final document (currently only for `html-single` mode).
+   As part of this, the `CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR` setting was
+   added (for `make` calls and used by `tools/gitlog2changelog.py.in` script),
+   and it defaults to `true` allowing for better ordered documents at the cost
+   of some memory during document generation. [#2510]
+
+ - added a `common/Makefile.am` build product for a new internal library
+   `libcommonstr.la` which allows a smaller selection of helper methods
+   for tools like `nut-scanner` which do not need the full `libcommon.la`
+   nor `libcommonclient.la`. [#2478, #2491]
+
+ - added a `drivers/Makefile.am` build product for a new internal library
+   `libserial-nutscan.la` to simplify `tools/nut-scanner/Makefile.am` recipes.
+   [#2490]
+
+ - build of `snmp-ups` and `netxml-ups` drivers now explicitly brings linker
+   dependency on chosen SSL libraries. [#2479]
+
+ - brought keyword dictionaries of `nutconf` and `augeas` NUT configuration
+   file parsers up to date; restored automated checks for `augeas` lenses.
+   [issue #657, issue #2294]
++
+   NOTE: Some known issues remain with augeas lens definitions so currently
+   they should be able to parse common simple use-cases but not certain types
+   of more complex configurations (e.g. some line patterns that involve too
+   many double-quote characters) which are valid for NUT proper. [#657]
+
+ - Cross-builds using only a host implementation of `pkg-config` program
+   should now ignore host `*.pc` files and avoid confusion.
+
+ - NUT CI farm build recipes, documentation and some `m4`/`configure.ac`
+   sources updated to handle a much larger build scope on MacOS. Also
+   migrated the builders to Apple Silicon from x86 (deprecated by CircleCI).
+   [#2502]
+
+ - Introduced a simple experiment to expose NUT client readings as filesystem
+   objects via FUSE, in `scripts/fuse/execfuse-nut` now. [#2591]
+
+
+Release notes for NUT 2.8.2 - what's new since 2.8.1
+----------------------------------------------------
 
 https://github.com/networkupstools/nut/milestone/10
 
@@ -87,6 +416,10 @@ https://github.com/networkupstools/nut/milestone/10
      `configure` script option `--with-debuginfo`. Note that default autoconf
      behavior usually embeds moderate optimizations and debug information on
      its own. [PR #2310]
+   * A fix applied among clean-ups between NUT v2.7.4 and v2.8.0 releases
+     backfired for `usbhid-ups` subdriver `belkin-hid` which in practice
+     relied on the broken older behavior; more details in its entry below.
+     [PR #2371]
 
  - nut-usbinfo.pl, nut-scanner and libnutscan:
    * Library API version for `libnutscan` was bumped from 2.2.0 to 2.5.0
@@ -146,6 +479,13 @@ https://github.com/networkupstools/nut/milestone/10
    * Driver programs with debug tracing support via `-D` CLI option and/or
      the `NUT_DEBUG_LEVEL` environment variable now check those earlier in
      their life-time, so that initialization routine can be debugged. [#2259]
+   * Multiple USB-capable drivers got options to customize `usb_config_index`
+     `usb_hid_rep_index`, `usb_hid_desc_index`, `usb_hid_ep_in` and
+     `usb_hid_ep_out` hardware connection settings via `ups.conf` options.
+     This is treated as experimental, not all code paths may be actually
+     using such values from `struct usb_communication_subdriver_t` rather
+     than hard-coded defaults. Discovery of correct values is up to the
+     user at the moment (using `lsusb`, internet search, luck...) [#2149]
 
  - nut-driver-enumerator (NDE) service/script:
    * The optional daemon mode (primarily useful for systems which monitor
@@ -173,6 +513,11 @@ https://github.com/networkupstools/nut/milestone/10
      useful as an UPS driver, not just a controller developer sandbox. [#2188]
    * `cps-hid` subdriver now supports devices branded as Cyber Energy and built
      by cooperation with Cyber Power Systems. [#2312]
+   * `belkin-hid` subdriver now supports Liebert PSI5 devices which have a
+     different numeric reading scale than earlier handled models. [issue #2271,
+     PR #2272, PR #2369] Generally the wrong-scale processing was addressed,
+     including a regression in NUT v2.8.0 which led to zero values
+     in voltage data points which NUT v2.7.4 reported well [#2371]
    * The `onlinedischarge` configuration flag name was too ambiguous and got
      deprecated (will be supported but no longer promoted by documentation),
      introducing `onlinedischarge_onbattery` as the meaningful alias. [#2213]
@@ -187,16 +532,25 @@ https://github.com/networkupstools/nut/milestone/10
        is not reported by the device (should be frequent by default, in case
        the UPS-reported state combination does reflect a bad power condition).
 
+ - nutdrv_qx driver:
+   * Fixed handling of `battery_voltage_reports_one_pack` configuration flag
+     introduced in NUT v2.8.1. [originally by PR #1279; fixed by PR #2324,
+     issue #2325]
+
  - Various code and documentation fixes for NSS crypto support. [#2274, #2268]
 
  - Laid foundations for the SmartNUT effort (aiming to integrate drivers with
    some other backends than the networked NUT data server process).
 
- - Eaton contributed recipes and scripts used to create the IPP for Unix bundle
-   (UPS software companion), delivering NUT packages with an interactive
+ - Eaton contributed recipes and scripts used to create the IPP for Unix
+   bundle (aka Eaton IPSS Unix or UPP), a freely available value-added
+   packaging of NUT distributed as the UPS software companion for OSes
+   where their more complex UPS monitoring/management tools had not been
+   ported. This allows for delivery of NUT packages with an interactive
    installer and some system integration scripts (events, notifications,
-   status, shutdown daemon...) -- provided "as is" at the moment, and may
-   later serve as foundation or inspiration for new NUT features. [#2288]
+   status, shutdown daemon...), and was contributed to the NUT upstream
+   project by Eaton -- provided "as is" at the moment, and may later serve
+   as foundation or inspiration for new NUT features. [#2288]
 
  - nutconf (C++ library and tool to read and manage NUT configuration files)
    was started in the open by Eaton employees and used in the IPP installer,
@@ -205,6 +559,12 @@ https://github.com/networkupstools/nut/milestone/10
    known deficiencies in Windows platform support, as well as some un-awareness
    about configuration key words which appeared in NUT since 2013. [#2290]
 
+ - The `tools/gitlog2changelog.py.in` script was revised, in particular to
+   convert section titles (with contributor names coming from Git metadata)
+   into plain ASCII character set, for `dblatex` versions which do not allow
+   diacritics and other kinds of non-trivial characters in sections. This can
+   cause successful builds of `ChangeLog.pdf` file on more platforms, but at
+   expense of a semi-cosmetic difference in those names. [PR #2360, PR #2366]
 
 Release notes for NUT 2.8.1 - what's new since 2.8.0
 ----------------------------------------------------
@@ -352,6 +712,12 @@ as part of https://github.com/networkupstools/nut/issues/1410 solution.
    * added `onlinedischarge_calibration` option for UPSes that report
      `OL+DISCHRG` when they are in calibration mode [#2104]
 
+ - riello_usb updates:
+   * added `localcalculation` option to compute `battery.runtime` and
+     `battery.charge` if the device provides bogus values [#1692, #1685]
+     (similar to `runtimecal` in some other drivers, may be refactored
+     to that configuration and logic model in later NUT releases)
+
  - powercom driver should now try harder to refresh data from device [#356]
 
  - tripplite_usb driver now supports configuration of `upsid` to match the
@@ -1424,6 +1790,8 @@ NOTE: There was no public NUT 2.7.0 release.
  - usbhid-ups: final fix for APC Back UPS ES.  APC Back UPS ES devices have
    buggy firmware, and this version does not cause a regression. The max_report
    variable should be set automatically based on the USB identification values.
+   * UPDATE: known as `maxreport` flag for `usbhid-ups` driver, and as a
+     `max_report_size` setting in code, as of NUT v2.8.2 release.
 
  - nut-scanner: fix crash
 
@@ -1484,6 +1852,7 @@ Release notes for NUT 2.6.5 - what's new since 2.6.4
 
  - mge-shut driver has been replaced by a new implementation (newmge-shut).
    In case of issue with this new version, users can revert to oldmge-shut.
+   UPDATE: oldmge-shut was dropped between 2.7.4 and 2.8.0 releases.
 
  - First NUT virtualization package: NUT now supports integration with
    VMware ESXI 5.0, through a native VIB package. This is, for the time
diff --git a/README.adoc b/README.adoc
index 2121366665..9bbbca12d7 100644
--- a/README.adoc
+++ b/README.adoc
@@ -217,6 +217,10 @@ which the larger potential sponsors consider when choosing how to help
 FOSS projects. Keeping the lights shining in such a large non-regression
 build matrix is a big undertaking!
 
+ifndef::pdf_format[]
+image:https://api.star-history.com/svg?repos=networkupstools/nut&type=Date[link="https://star-history.com/#networkupstools/nut&Date" alt="NUT GitHub Star History Chart"]
+endif::pdf_format[]
+
 See <<acknowledgements-ci-ops,acknowledgements of organizations which help
 with NUT CI and other daily operations>> for an overview of the shared effort.
 =====
@@ -825,8 +829,9 @@ endif::env-github[]
   preview tarballs with binaries).
 
 | image:images/ci/DO_Powered_by_Badge_blue_140pxW.png[alt="DigitalOcean logo",width="140",height="29",link="https://www.digitalocean.com/?refcode=d2fbf2b9e082&utm_campaign=Referral_Invite&utm_medium=Referral_Program&utm_source=badge"]
-| The link:https://www.digitalocean.com/?refcode=d2fbf2b9e082&utm_campaign=Referral_Invite&utm_medium=Referral_Program&utm_source=badge[DigitalOcean] droplets allow us to host
-  NUT CI farm build agents, and eventually re-house the Jenkins controller too.
+| The link:https://www.digitalocean.com/?refcode=d2fbf2b9e082&utm_campaign=Referral_Invite&utm_medium=Referral_Program&utm_source=badge[DigitalOcean]
+  droplets allow us to host NUT CI farm Jenkins controller and the build agents
+  for multiple operating systems.
 
 | image:images/ci/gandi-ar21.png[alt="Gandi.Net logo",width="120",height="60",link="https://www.gandi.net/"]
 | link:https://www.gandi.net/[Gandi.Net] took up the costs of NUT DNS hosting.
diff --git a/UPGRADING.adoc b/UPGRADING.adoc
index 2ede05ee5a..98c4e492fc 100644
--- a/UPGRADING.adoc
+++ b/UPGRADING.adoc
@@ -26,6 +26,110 @@ Changes from 2.8.2 to 2.8.3
 
 - PLANNED: Keep track of any further API clean-up?
 
+- NUT development snapshots can now have more version components than the
+  standard semantic versioning triplet, optionally adding the amount of
+  commits on the development trunk since previous release, and the amount
+  of commits on a feature branch that are unique to it.  Release artifacts
+  that have zeroes in both positions would have them stripped and still
+  have the standard "semver" exposed, but the development snapshots can
+  now be more reasonably upgraded with automated tooling. A copy of the
+  current version information would be embedded into "dist" archives as
+  a `VERSION_DEFAULT` file, so it can be used without git. Certain distros
+  can benefit from a `VERSION_FORCED` file or a `NUT_VERSION_FORCED`
+  environment variable exported from their build system, e.g. via
+  `echo NUT_VERSION_FORCED=1.1.1 > VERSION_FORCED`. Unfortunately, some
+  appliances tag all software the same with their firmware version;
+  if this is required, a (NUT_)VERSION_FORCED_SEMVER envvar or file can
+  help identify the actual NUT release version triplet used on the box.
+  Please use it, it immensely helps with community troubleshooting!
+  [issue #1949]
+
+- `upsmon` should now integrate natively with systemd-driven OS sleep events
+  (built with systemd version 221 or newer "inhibitor interface"), so various
+  hacks previously packaged into `/usr/lib/systemd/system-sleep/` scripts or
+  units requiring/conflicting with the `sleep.target` may be obsolete.
+  For fallback with older systemd, a `nut-sleep.service` is provided now.
+  [#1070, #2596, #2597]
+
+- `usbhid-ups` subdriver `PowerCOM HID` subdriver sent UPS `shutdown` and
+  `stayoff` commands in wrong byte order, at least for devices currently
+  in the field. Driver now sends the commands in a way that satisfies new
+  devices; just in case a flag toggle `powercom_sdcmd_byte_order_fallback`
+  was added to set the old behavior (if some devices do need it). [PR #2480]
+
+- Added support for `lbrb_log_delay_sec=N` setting to delay propagation of
+  `LB` or `LB+RB` state (buggy with APC BXnnnnMI devices/firmwares issued
+  circa 2023-2024 which flood the logs with spurious LOWBATT and REPLACEBATT
+  events). This may work better for some devices when combined with flags
+  like `onlinedischarge_calibration` and `lbrb_log_delay_without_calibrating`.
+  [#2347]
+
+- Enabled installation of built PDF and HTML (including man page renditions)
+  files under the configured `docdir`. It seems previously they were only
+  built (if requested) but not installed via `make`, unlike the common man
+  pages which are delivered automatically. Packaging recipes can likely
+  be simplified now. [#2445]
+
+- A `NUT_DEBUG_SYSLOG` environment variable was introduced to tweak activation
+  of syslog message emission (and related detachment of `stderr` when daemons
+  are backgrounding), which can be useful for systemd service units. It can be
+  set via `nut.conf` file for all standard consumers, or patched/dropped-in to
+  systemd unit definitions specifically (less recommended, but may be easier
+  to package). The positive effect would be avoiding duplicate logging as both
+  `syslog` and `stderr` ending up in the same journal. [#2394]
+
+- A `CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR` setting was added (for `make`
+  calls and used by `tools/gitlog2changelog.py.in` script), and it defaults
+  to `true` allowing for better ordered documents at the cost of some memory
+  during document generation. Resource-constrained builders (working from
+  a Git workspace, not tarball archives) may have to set it to `false` when
+  calling `make` for NUT. [#2510]
+
+- NUT products like `nut-scanner`, which dynamically load shared libraries
+  at run-time without persistent pre-linking, should now know the library
+  file names that were present during build (likely encumbered with version
+  suffixes), and prefer them over plain `libname.so` patterns used previously
+  (which on some platforms are only delivered by development packages as
+  symlinks). Packaging recipes can likely be simplified now: some distros
+  certainly did patch NUT source to similar effect). [#2431]
+
+- Numerous changes to `nut-scanner` and symbols that its `libnutscan.so`
+  delivers have caused a library version bump.  New methods have been added
+  and one structure (`nutscan_ipmi_t`) updated in a (hopefully) backwards
+  compatible manner. [PR #2523, issue #2244 and numerous PRs for it]
+
+- Internal API change for `sendsignalpid()` and `sendsignalfn()` methods,
+  which can impact NUT forks which build using `libcommon.la` and similar
+  libraries.  Added new last argument with `const char *progname` (may be
+  `NULL`) to check that we are signalling an expected program name when we
+  work with a PID.  With the same effort, NUT programs which deal with PID
+  files to send signals (`upsd`, `upsmon`, drivers and `upsdrvctl`) would
+  now default to a safety precaution -- checking that the running process
+  with that PID has the expected program name (on platforms where we can
+  determine one). This might introduce regressions for heavily customized
+  NUT builds (e.g. embedded in NAS or similar devices) whose binary file
+  names differ significantly from a `progname` defined in the respective
+  NUT source file, so a boolean `NUT_IGNORE_CHECKPROCNAME` environment
+  variable support was added to optionally disable this verification.
+  Also the NUT daemons should request to double-check against their
+  run-time process name (if it can be detected). [issue #2463]
+
+- More environment variable support was added to NUT programs, primarily
+  aimed at wrappers such as init scripts and service unit definitions,
+  allowing to tweak what (and whether) they write into debug traces, and
+  so "make noise" or "bring invaluable insights" to logs or terminal;
+  they can generally be used for services and init scripts via `nut.conf`:
+  * See `NUT_IGNORE_CHECKPROCNAME` and `NUT_DEBUG_SYSLOG` above. [#1915]
+  * A `NUT_QUIET_INIT_BANNER` envvar (presence or "true" value) prevents
+    tool name and NUT version banner from being printed out when programs
+    start. [issues #1789 vs. #316]
+
+- A `configure` script option to `--enable-NUT_STRARG-always` was added
+  to enable the `NUT_STRARG` macro (to handle `NULL` string printing)
+  even if system libraries seem to safely support this behavior natively.
+  This should primarily help against overly zealous static analysis tools
+  in recent compiler generations. [#2585]
+
 
 Changes from 2.8.1 to 2.8.2
 ---------------------------
@@ -44,6 +148,13 @@ Changes from 2.8.1 to 2.8.2
   appear as comments, or enabled by specifying the `-U` command-line
   option several times. [#2221]
 
+- The `tools/gitlog2changelog.py.in` script was revised, in particular to
+  convert section titles (with contributor names) into plain ASCII character
+  set, for `dblatex` versions which do not allow diacritics and other kinds
+  of non-trivial characters in sections. A number of other projects seem to
+  use the NUT version of the script, and are encouraged to look at related
+  changes in `configure.ac` and `Makefile.am` recipes. [PR #2360, PR #2366]
+
 Changes from 2.8.0 to 2.8.1
 ---------------------------
 
@@ -414,17 +525,20 @@ Changes from 2.6.4 to 2.6.5
 ---------------------------
 
 - users are encouraged to update to NUT 2.6.5, to fix a regression in
-upssched.
+  upssched.
+
 - mge-shut driver has been replaced by a new implementation (newmge-shut).
-In case of issue with this new version, users can revert to oldmge-shut.
+  In case of issue with this new version, users can revert to oldmge-shut.
+  UPDATE: oldmge-shut was dropped between 2.7.4 and 2.8.0 releases.
 
 Changes from 2.6.3 to 2.6.4
 ---------------------------
 
 - users are encouraged to update to NUT 2.6.4, to fix upsd vulnerability
-(CVE-2012-2944: upsd can be remotely crashed).
+  (CVE-2012-2944: upsd can be remotely crashed).
+
 - users of the bestups driver are encouraged to switch to blazer_ser,
-since bestups will soon be deprecated.
+  since bestups will soon be deprecated.
 
 Changes from 2.6.2 to 2.6.3
 ---------------------------
@@ -435,7 +549,7 @@ Changes from 2.6.1 to 2.6.2
 ---------------------------
 
 - apcsmart driver has been replaced by a new implementation. In case of issue
-with this new version, users can revert to apcsmart-old.
+  with this new version, users can revert to apcsmart-old.
 
 Changes from 2.6.0 to 2.6.1
 ---------------------------
@@ -446,9 +560,10 @@ Changes from 2.4.3 to 2.6.0
 ---------------------------
 
 - users of the megatec and megatec_usb drivers must respectively switch to
-blazer_ser and blazer_usb.
+  blazer_ser and blazer_usb.
+
 - users of the liebertgxt2 driver are advised that the driver name has changed
-to liebert-esp2.
+  to liebert-esp2.
 
 Changes from 2.4.2 to 2.4.3
 ---------------------------
@@ -459,11 +574,12 @@ Changes from 2.4.1 to 2.4.2
 ---------------------------
 
 - The default subdriver for the blazer_usb driver USB id 06da:0003 has changed.
-If you use such a device and it is no longer working with this driver, override
-the 'subdriver' default in 'ups.conf' (see man 8 blazer).
+  If you use such a device and it is no longer working with this driver,
+  override the 'subdriver' default in 'ups.conf' (see man 8 blazer).
+
 - NUT ACL and the allowfrom mechanism has been replaced in 2.4.0 by the LISTEN
-directive and tcp-wrappers respectively. This information was missing below, so
-a double note has been added.
+  directive and tcp-wrappers respectively. This information was missing below,
+  so a double note has been added.
 
 Changes from 2.4.0 to 2.4.1
 ---------------------------
@@ -474,157 +590,175 @@ Changes from 2.2.2 to 2.4.0
 ---------------------------
 
 - The nut.conf file has been introduced to standardize startup configuration
-across the various systems.
+  across the various systems.
+
 - The cpsups and nitram drivers have been replaced by the powerpanel driver,
-and removed from the tree. The cyberpower driver may suffer the same in the
-future.
+  and removed from the tree. The cyberpower driver may suffer the same in the
+  future.
+
 - The al175 and energizerups drivers have been removed from the tree, since
-these were tagged broken for a long time.
+  these were tagged broken for a long time.
+
 - Developers of external client application using libupsclient must rename
-their "UPSCONN" client structure to "UPSCONN_t".
+  their "UPSCONN" client structure to "UPSCONN_t".
+
 - The upsd server will now disconnect clients that remain silent for more than
-60 seconds.
+  60 seconds.
+
 - The files under scripts/python/client are distributed under GPL 3+, whereas
-the rest of the files are distributed under GPL 2+. Refer to COPYING for more
-information.
+  the rest of the files are distributed under GPL 2+. Refer to COPYING for more
+  information.
+
 - The generated udev rules file has been renamed with dash only, no underscore
-anymore (ie 52-nut-usbups.rules instead of 52_nut-usbups.rules)
+  anymore (i.e. 52-nut-usbups.rules instead of 52_nut-usbups.rules)
 
 Changes from 2.2.1 to 2.2.2
 ---------------------------
 
 - The configure option "--with-lib" has been replaced by "--with-dev".
-This enable the additional build and distribution of the static
-version of libupsclient, along with the pkg-config helper and manual
-pages. The default configure option is to distribute only the shared
-version of libupsclient. This can be overridden by using the
-"--disable-shared" configure option (distribute static only binaries).
+  This enable the additional build and distribution of the static
+  version of libupsclient, along with the pkg-config helper and manual
+  pages. The default configure option is to distribute only the shared
+  version of libupsclient. This can be overridden by using the
+  "--disable-shared" configure option (distribute static only binaries).
+
 - The UPS poweroff handling of the usbhid-ups driver has been reworked.
-Though regression is not expected, users of this driver are
-encouraged to test this feature by calling "upsmon -c fsd" and
-report any issue on the NUT mailing lists.
+  Though regression is not expected, users of this driver are
+  encouraged to test this feature by calling "upsmon -c fsd" and
+  report any issue on the NUT mailing lists.
 
 Changes from 2.2.0 to 2.2.1
 ---------------------------
 
 - nothing that affects upgraded systems.
-(The below message is repeated due to previous omission)
+  (The below message is repeated due to previous omission)
+
 - Developers of external client application using libupsclient are
-encouraged to rename their "UPSCONN" client structure to "UPSCONN_t"
-since the former will disappear by the release of NUT 2.4.
+  encouraged to rename their "UPSCONN" client structure to "UPSCONN_t"
+  since the former will disappear by the release of NUT 2.4.
 
 Changes from 2.0.5 to 2.2.0
 ---------------------------
 
 - users of the newhidups driver are advised that the driver name has changed
-to usbhid-ups.
+  to usbhid-ups.
+
 - users of the hidups driver must switch to usbhid-ups.
+
 - users of the following drivers (powermust, blazer, fentonups, mustek,
-esupssmart, ippon, sms) must switch to megatec, which replaces
-all these drivers.  Please refer to doc/megatec.txt for details.
+  esupssmart, ippon, sms) must switch to megatec, which replaces
+  all these drivers.  Please refer to doc/megatec.txt for details.
+
 - users of the mge-shut driver are encouraged to test newmge-shut, which
-is an alternate driver scheduled to replace mge-shut,
+  is an alternate driver scheduled to replace mge-shut,
+
 - users of the cpsups driver are encouraged to switch to powerpanel which
-is  scheduled to replace cpsups,
+  is scheduled to replace cpsups,
+
 - packagers will have to rework the whole nut packaging due to the
-major changes in the build system (completely modified, and now using
-automake). Refer to packaging/debian/ for an example of migration.
+  major changes in the build system (completely modified, and now using
+  automake). Refer to packaging/debian/ for an example of migration.
+
 - specifying '-a <id>' is now mandatory when starting a driver manually,
-ie not using upsdrvctl.
+  i.e. not using upsdrvctl.
+
 - Developers of external client application using libupsclient are
-encouraged to rename the "UPSCONN" client structure to "UPSCONN_t"
-since the former will disappear by the release of NUT 2.4.
+  encouraged to rename the "UPSCONN" client structure to "UPSCONN_t"
+  since the former will disappear by the release of NUT 2.4.
 
 Changes from 2.0.4 to 2.0.5
 ---------------------------
 
 - users of the newhidups driver: the driver is now more strict about
-refusing to connect to unknown devices. If your device was
-previously supported, but fails to be recognized now, add
-'productid=XXXX' to ups.conf. Please report the device to the NUT
-developer's mailing list.
+  refusing to connect to unknown devices. If your device was
+  previously supported, but fails to be recognized now, add
+  'productid=XXXX' to ups.conf. Please report the device to the NUT
+  developer's mailing list.
 
 Changes from 2.0.3 to 2.0.4
 ---------------------------
 
 - nothing that affects upgraded systems.
+
 - users of the following drivers (powermust, blazer, fentonups, mustek,
-esupssmart, ippon, sms, masterguard) are encouraged to switch to megatec,
-which should replace all these drivers by nut 2.2. For more information,
-please refer to doc/megatec.txt
+  esupssmart, ippon, sms, masterguard) are encouraged to switch to megatec,
+  which should replace all these drivers by nut 2.2. For more information,
+  please refer to doc/megatec.txt
 
 Changes from 2.0.2 to 2.0.3
 ---------------------------
 
 - nothing that affects upgraded systems.
+
 - hidups users are encouraged to switch to newhidups, as hidups will be
-removed by nut 2.2.
+  removed by nut 2.2.
 
 Changes from 2.0.1 to 2.0.2
 ---------------------------
 
 - The newhidups driver, which is the long run USB support approach,
-needs hotplug files installed to setup the right permissions on
-device file to operate. Check newhidups manual page for more information.
+  needs hotplug files installed to setup the right permissions on
+  device file to operate. Check newhidups manual page for more information.
 
 Changes from 2.0.0 to 2.0.1
 ---------------------------
 
 - The cyberpower1100 driver is now called cpsups since it supports
-more than just one model.  If you use this driver, be sure to remove
-the old binary and update your ups.conf 'driver=' setting with the
-new name.
+  more than just one model.  If you use this driver, be sure to remove
+  the old binary and update your ups.conf 'driver=' setting with the
+  new name.
 
 - The upsstats.html template page has been changed slightly to reflect
-better HTML compliance, so you may want to update your installed copy
-accordingly.  If you've customized your file, don't just copy the new
-one over it, or your changes will be lost!
+  better HTML compliance, so you may want to update your installed copy
+  accordingly.  If you've customized your file, don't just copy the new
+  one over it, or your changes will be lost!
 
 Changes from 1.4.0 to 2.0.0
 ---------------------------
 
 - The sample config files are no longer installed by default.  If you
-want to install them, use 'make install-conf' for the main programs,
-and 'make install-cgi-conf' for the CGI programs.
+  want to install them, use 'make install-conf' for the main programs,
+  and 'make install-cgi-conf' for the CGI programs.
 
 - ACCESS is no longer supported in upsd.conf.  Use ACCEPT and REJECT.
-Old way:
 
+  * Old way:
++
 	ACCESS grant all adminbox
 	ACCESS grant all webserver
 	ACCESS deny all all
 
-New way:
-
+  * New way:
++
 	ACCEPT adminbox
 	ACCEPT webserver
 	REJECT all
 
-Note that ACCEPT and REJECT can take multiple arguments, so this
-will also work:
-
+  * Note that ACCEPT and REJECT can take multiple arguments, so this
+    will also work:
++
 	ACCEPT adminbox webserver
 	REJECT all
 
 - The drivers no longer support sddelay in ups.conf or -d on the
-command line.  If you need a delay after calling 'upsdrvctl
-shutdown', add a call to sleep in your shutdown script.
+  command line.  If you need a delay after calling 'upsdrvctl
+  shutdown', add a call to sleep in your shutdown script.
 
 - The templates used by upsstats have changed considerably to reflect
-the new variable names.  If you use upsstats, you will need to
-install new copies or edit your existing files to use the new names.
+  the new variable names.  If you use upsstats, you will need to
+  install new copies or edit your existing files to use the new names.
 
 - Nobody needed UDP mode, so it has been removed.  The only users
-seemed to be a few people like me with ancient asapm-ups binaries.
-If you really want to run asapm-ups again, bug me for the new patch
-which makes it work with upsclient.
+  seemed to be a few people like me with ancient asapm-ups binaries.
+  If you really want to run asapm-ups again, bug me for the new patch
+  which makes it work with upsclient.
 
 - 'make install-misc' is now 'make install-lib'.  The misc directory
-has been gone for a long time, and the target was ambiguous.
+  has been gone for a long time, and the target was ambiguous.
 
 - The newapc driver has been renamed to apcsmart.  If you previously
-used newapc, make sure you delete the old binary and fix your
-ups.conf.  Otherwise, you may run the old driver from 1.4.
+  used newapc, make sure you delete the old binary and fix your
+  ups.conf.  Otherwise, you may run the old driver from 1.4.
 
 File trimmed here on changes from 1.2.2 to 1.4.0
 ------------------------------------------------
diff --git a/appveyor.yml b/appveyor.yml
index ba5101aa18..2c0d712164 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -6,7 +6,7 @@
 # https://www.appveyor.com/docs/build-configuration/
 # https://www.appveyor.com/docs/windows-images-software/
 
-version: 2.8.1.{build}-{branch}
+version: 2.8.2.{build}-{branch}
 
 # base image
 image: Visual Studio 2022
diff --git a/autogen.sh b/autogen.sh
index afcf3d647b..f59d93e886 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -24,6 +24,8 @@ else
 	DEBUG=false
 fi
 
+NUT_VERSION_QUERY=UPDATE_FILE "`dirname $0`"/tools/gitlog2version.sh
+
 if [ -n "${PYTHON-}" ] ; then
 	# May be a name/path of binary, or one with args - check both
 	(command -v "$PYTHON") \
@@ -165,6 +167,18 @@ fi >&2
 [ -f NEWS ] || { echo "Please see NEWS.adoc for actual contents" > NEWS; }
 [ -f README ] || { echo "Please see README.adoc for actual contents" > README; }
 
+# Try to serve a fresh one at least when we remake from scratch like this
+# Note to not do it forcefully during `configure` or rebuild
+rm -f include/nut_version.h || true
+
+echo "----------------------------------------------------------------------"
+echo "Please note that on some systems the routine below can complain that "
+echo "  > configure.ac: warning: AC_INIT: not a literal: m4_esyscmd_s(...)"
+echo "but still does the right thing about PACKAGE_VERSION and PACKAGE_URL settings."
+echo "Check if your distro provides an 'autoconf-archive' package anf if it helps."
+echo "Please post an issue in NUT bug tracker with platform details if it does not."
+echo "----------------------------------------------------------------------"
+
 echo "Calling autoreconf..."
 AUTOTOOL_RES=0
 if $DEBUG ; then
@@ -178,16 +192,19 @@ fi
 
 [ "$AUTOTOOL_RES" = 0 ] && [ -s configure ] && [ -x configure ] \
 || { cat << EOF
+----------------------------------------------------------------------
 FAILED: did not generate an executable configure script!
 
 # Note: on some systems "autoreconf", "automake" et al are dispatcher
 # scripts, and need you to explicitly say which version you want, e.g.
 #    export AUTOCONF_VERSION=2.65 AUTOMAKE_VERSION=1.13
 # If you get issues with AC_DISABLE_STATIC make sure you have libtool.
+#
 # If it complains about "too few" or "excess" "arguments to builtin ifdef",
 # check the configure.ac line it refers to and un-comment (or comment away)
 # the third argument for AM_SILENT_RULES check, or comment away the whole
 # "ifdef" block if your autotools still would not grok it.
+----------------------------------------------------------------------
 EOF
 	exit 1
 } >&2
@@ -216,13 +233,20 @@ else
 	CONFIG_SHELL="`head -1 configure | sed 's,^#!,,'`"
 fi
 
-# NOTE: Unquoted, may be multi-token
+# NOTE: Unquoted CONFIG_SHELL, may be multi-token
 $CONFIG_SHELL -n configure 2>/dev/null >/dev/null \
-|| { echo "FAILED: configure script did not pass shell interpreter syntax checks with $CONFIG_SHELL" >&2
+|| {
+	echo "----------------------------------------------------------------------" >&2
+	echo "FAILED: configure script did not pass shell interpreter syntax checks with $CONFIG_SHELL" >&2
 	echo "NOTE: If you are using an older OS release, try executing the script with" >&2
 	echo "a more functional shell implementation (dtksh, bash, dash...)" >&2
 	echo "You can re-run this script with a CONFIG_SHELL in environment" >&2
+	echo "----------------------------------------------------------------------" >&2
 	exit 1
 }
 
-echo "The generated configure script passed shell interpreter syntax checks"
+echo "----------------------------------------------------------------------"
+echo "SUCCESS: The generated configure script passed shell interpreter syntax checks"
+echo "Please proceed by running './configure --with-many-desired-options'"
+echo "For details check './configure --help' or docs/configure.txt in NUT sources"
+echo "----------------------------------------------------------------------"
diff --git a/ci_build.sh b/ci_build.sh
index 83e395e447..12cec3a01b 100755
--- a/ci_build.sh
+++ b/ci_build.sh
@@ -55,7 +55,9 @@ case "$BUILD_TYPE" in
     fightwarn-gcc)
         CC="gcc"
         CXX="g++"
-        CPP="cpp"
+        # Avoid "cpp" directly as it may be too "traditional"
+        #CPP="cpp"
+        CPP="gcc -E"
         BUILD_TYPE=fightwarn
         ;;
     fightwarn-clang)
@@ -191,16 +193,22 @@ fi
 # (note: a "-" value requests to NOT use a CI_CCACHE_SYMLINKDIR;
 # ccache may still be used via prefixing if the tool is found in
 # the PATH, unless you export CI_CCACHE_USE=no also):
-if [ -z "${CI_CCACHE_SYMLINKDIR-}" ] ; then
-    for D in \
+propose_CI_CCACHE_SYMLINKDIR() {
+    echo \
         "/usr/lib/ccache" \
         "/mingw64/lib/ccache/bin" \
         "/mingw32/lib/ccache/bin" \
         "/usr/lib64/ccache" \
         "/usr/libexec/ccache" \
         "/usr/lib/ccache/bin" \
-        "/usr/local/lib/ccache" \
-    ; do
+        "/usr/local/lib/ccache"
+
+    if [ -n "${HOMEBREW_PREFIX-}" ]; then
+        echo "${HOMEBREW_PREFIX}/opt/ccache/libexec"
+    fi
+}
+if [ -z "${CI_CCACHE_SYMLINKDIR-}" ] ; then
+    for D in `propose_CI_CCACHE_SYMLINKDIR` ; do
         if [ -d "$D" ] ; then
             if ( ls -la "$D" | grep -e ' -> .*ccache' >/dev/null) \
             || ( test -n "`find "$D" -maxdepth 1 -type f -exec grep -li ccache '{}' \;`" ) \
@@ -462,7 +470,7 @@ if [ -z "${CANBUILD_LIBGD_CGI-}" ]; then
 
     # NUT CI farm with Jenkins can build it; Travis could not
     [[ "$CI_OS_NAME" = "freebsd" ]] && CANBUILD_LIBGD_CGI=yes \
-    || [[ "$TRAVIS_OS_NAME" = "freebsd" ]] && CANBUILD_LIBGD_CGI=no
+    || { [[ "$TRAVIS_OS_NAME" = "freebsd" ]] && CANBUILD_LIBGD_CGI=no ; }
 
     # See also below for some compiler-dependent decisions
 fi
@@ -540,8 +548,10 @@ configure_nut() {
       echo "=== CC='$CC' CXX='$CXX' CPP='$CPP'"
       [ -z "${CI_SHELL_IS_FLAKY-}" ] || echo "=== CI_SHELL_IS_FLAKY='$CI_SHELL_IS_FLAKY'"
       $CI_TIME $CONFIGURE_SCRIPT "${CONFIG_OPTS[@]}" \
+      && echo "$0: configure phase complete (0)" >&2 \
       && return 0 \
       || { RES_CFG=$?
+        echo "$0: configure phase complete ($RES_CFG)" >&2
         echo "FAILED ($RES_CFG) to configure nut, will dump config.log in a second to help troubleshoot CI" >&2
         echo "    (or press Ctrl+C to abort now if running interactively)" >&2
         sleep 5
@@ -573,6 +583,12 @@ build_to_only_catch_errors_target() {
 
     # Sub-shells to avoid crashing with "unhandled" faults in "set -e" mode:
     ( echo "`date`: Starting the parallel build attempt (quietly to build what we can) for '$@' ..."; \
+      if [ -n "$PARMAKE_FLAGS" ]; then
+        echo "For parallel builds, '$PARMAKE_FLAGS' options would be used"
+      fi
+      if [ -n "$MAKEFLAGS" ]; then
+        echo "Generally, MAKEFLAGS='$MAKEFLAGS' options would be passed"
+      fi
       ( case "${CI_PARMAKE_VERBOSITY}" in
         silent)
           # Note: stderr would still expose errors and warnings (needed for
@@ -585,7 +601,12 @@ build_to_only_catch_errors_target() {
         default)
           $CI_TIME $MAKE -k $PARMAKE_FLAGS "$@" ;;
       esac ) && echo "`date`: SUCCESS" ; ) || \
-    ( echo "`date`: Starting the sequential build attempt (to list remaining files with errors considered fatal for this build configuration) for '$@'..."; \
+    ( RET=$?
+      if [ "$CI_FAILFAST" = true ]; then
+        echo "===== Aborting after parallel build attempt failure for '$*' because CI_FAILFAST=$CI_FAILFAST" >&2
+        exit $RET
+      fi
+      echo "`date`: Starting the sequential build attempt (to list remaining files with errors considered fatal for this build configuration) for '$@'..."; \
       $CI_TIME $MAKE $MAKE_FLAGS_VERBOSE "$@" -k ) || return $?
     return 0
 }
@@ -646,7 +667,9 @@ check_gitignore() {
     # Shell-glob filename pattern for points of interest to git status
     # and git diff; note that filenames starting with a dot should be
     # reported by `git status -- '*'` and not hidden.
-    [ -n "${FILE_GLOB-}" ] || FILE_GLOB='*'
+    [ -n "${FILE_GLOB-}" ] || FILE_GLOB="'*'"
+    # Always filter these names away:
+    FILE_GLOB_EXCLUDE="':!.ci*.log*' ':!VERSION_DEFAULT' ':!VERSION_FORCED*'"
     [ -n "${GIT_ARGS-}" ] || GIT_ARGS='' # e.g. GIT_ARGS="--ignored"
     # Display contents of the diff?
     # (Helps copy-paste from CI logs to source to amend quickly)
@@ -661,12 +684,11 @@ check_gitignore() {
 
     # One invocation should report to log if there was any discrepancy
     # to report in the first place (GITOUT may be empty without error):
-    GITOUT="`git status $GIT_ARGS -s -- "${FILE_GLOB}"`" \
+    GITOUT="`git status $GIT_ARGS -s -- ${FILE_GLOB} ${FILE_GLOB_EXCLUDE}`" \
     || { echo "WARNING: Could not query git repo while in `pwd`" >&2 ; GITOUT=""; }
 
     if [ -n "${GITOUT-}" ] ; then
         echo "$GITOUT" \
-        | grep -E -v '^.. \.ci.*\.log.*' \
         | grep -E "${FILE_REGEX}"
     else
         echo "Got no output and no errors querying git repo while in `pwd`: seems clean" >&2
@@ -674,12 +696,12 @@ check_gitignore() {
     echo "==="
 
     # Another invocation checks that there was nothing to complain about:
-    if [ -n "`git status $GIT_ARGS -s "${FILE_GLOB}" | grep -E -v '^.. \.ci.*\.log.*' | grep -E "^.. ${FILE_REGEX}"`" ] \
+    if [ -n "`git status $GIT_ARGS -s ${FILE_GLOB} ${FILE_GLOB_EXCLUDE} | grep -E "^.. ${FILE_REGEX}"`" ] \
     && [ "$CI_REQUIRE_GOOD_GITIGNORE" != false ] \
     ; then
         echo "FATAL: There are changes in $FILE_DESCR files listed above - tracked sources should be updated in the PR (even if generated - not all builders can do so), and build products should be added to a .gitignore file, everything made should be cleaned and no tracked files should be removed! You can 'export CI_REQUIRE_GOOD_GITIGNORE=false' if appropriate." >&2
         if [ "$GIT_DIFF_SHOW" = true ]; then
-            PAGER=cat git diff -- "${FILE_GLOB}" || true
+            PAGER=cat git diff -- ${FILE_GLOB} ${FILE_GLOB_EXCLUDE} || true
         fi
         echo "==="
         return 1
@@ -687,6 +709,45 @@ check_gitignore() {
     return 0
 }
 
+consider_cleanup_shortcut() {
+    # Note: modern auto(re)conf requires pkg-config to generate the configure
+    # script, so to stage the situation of building without one (as if on an
+    # older system) we have to remove it when we already have the script.
+    # This matches the use-case of distro-building from release tarballs that
+    # include all needed pre-generated files to rely less on OS facilities.
+    DO_REGENERATE=false
+    if [ x"${CI_REGENERATE}" = xtrue ] ; then
+        echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because CI_REGENERATE='${CI_REGENERATE}'"
+        DO_REGENERATE=true
+    fi
+
+    if [ -s Makefile ]; then
+        if [ -n "`find "${SCRIPTDIR}" -name configure.ac -newer "${CI_BUILDDIR}"/configure`" ] \
+        || [ -n "`find "${SCRIPTDIR}" -name '*.m4' -newer "${CI_BUILDDIR}"/configure`" ] \
+        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile`" ] \
+        || [ -n "`find "${SCRIPTDIR}" -name Makefile.in -newer "${CI_BUILDDIR}"/Makefile`" ] \
+        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile.in`" ] \
+        ; then
+            # Avoid reconfiguring just for the sake of distclean
+            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because recipes changed"
+            DO_REGENERATE=true
+        fi
+    fi
+
+    # When itertating configure.ac or m4 sources, we can end up with an
+    # existing but useless scropt file - nuke it and restart from scratch!
+    if [ -s "${CI_BUILDDIR}"/configure ] ; then
+        if ! sh -n "${CI_BUILDDIR}"/configure 2>/dev/null ; then
+            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because current configure script syntax is broken"
+            DO_REGENERATE=true
+        fi
+    fi
+
+    if $DO_REGENERATE ; then
+        rm -f "${CI_BUILDDIR}"/Makefile "${CI_BUILDDIR}"/configure "${CI_BUILDDIR}"/include/config.h "${CI_BUILDDIR}"/include/config.h.in "${CI_BUILDDIR}"'/include/config.h.in~'
+    fi
+}
+
 can_clean_check() {
     if [ "${DO_CLEAN_CHECK-}" = "no" ] ; then
         # NOTE: Not handling here particular DO_MAINTAINER_CLEAN_CHECK or DO_DIST_CLEAN_CHECK
@@ -956,13 +1017,13 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
         # Note: can be a multi-token name like "clang -E" or just not a full pathname
         ( [ -x "$CPP" ] || $CPP --help >/dev/null 2>/dev/null ) && export CPP
     else
-        if is_gnucc "cpp" ; then
-            CPP=cpp && export CPP
-        else
-            case "$COMPILER_FAMILY" in
-                CLANG*|GCC*) CPP="$CC -E" && export CPP ;;
-            esac
-        fi
+        # Avoid "cpp" directly as it may be too "traditional"
+        case "$COMPILER_FAMILY" in
+            CLANG*|GCC*) CPP="$CC -E" && export CPP ;;
+            *) if is_gnucc "cpp" ; then
+                CPP=cpp && export CPP
+               fi ;;
+        esac
     fi
 
     if [ -z "${CANBUILD_LIBGD_CGI-}" ]; then
@@ -987,14 +1048,6 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
         fi
     fi
 
-    # Note: Potentially there can be spaces in entries for multiple
-    # *FLAGS here; this should be okay as long as entry expands to
-    # one token when calling shell (may not be the case for distcheck)
-    CONFIG_OPTS+=("CFLAGS=-I${BUILD_PREFIX}/include ${CFLAGS}")
-    CONFIG_OPTS+=("CPPFLAGS=-I${BUILD_PREFIX}/include ${CPPFLAGS}")
-    CONFIG_OPTS+=("CXXFLAGS=-I${BUILD_PREFIX}/include ${CXXFLAGS}")
-    CONFIG_OPTS+=("LDFLAGS=-L${BUILD_PREFIX}/lib ${LDFLAGS}")
-
     DEFAULT_PKG_CONFIG_PATH="${BUILD_PREFIX}/lib/pkgconfig"
     SYSPKG_CONFIG_PATH="" # Let the OS guess... usually
     case "`echo "$CI_OS_NAME" | tr 'A-Z' 'a-z'`" in
@@ -1018,6 +1071,63 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
                     ;;
             esac
             ;;
+        *darwin*|*macos*|*osx*)
+            # Architecture-dependent base dir, e.g.
+            # * /usr/local on macos x86
+            # * /opt/homebrew on macos Apple Silicon
+            if [ -n "${HOMEBREW_PREFIX-}" -a -d "${HOMEBREW_PREFIX-}" ]; then
+                echo "Homebrew: export general pkg-config location and C/C++/LD flags for the platform"
+                SYS_PKG_CONFIG_PATH="${HOMEBREW_PREFIX}/lib/pkgconfig"
+                CFLAGS="${CFLAGS-} -Wno-poison-system-directories -Wno-deprecated-declarations -isystem ${HOMEBREW_PREFIX}/include -I${HOMEBREW_PREFIX}/include"
+                #CPPFLAGS="${CPPFLAGS-} -Wno-poison-system-directories -Wno-deprecated-declarations -isystem ${HOMEBREW_PREFIX}/include -I${HOMEBREW_PREFIX}/include"
+                CXXFLAGS="${CXXFLAGS-} -Wno-poison-system-directories -isystem ${HOMEBREW_PREFIX}/include -I${HOMEBREW_PREFIX}/include"
+                LDFLAGS="${LDFLAGS-} -L${HOMEBREW_PREFIX}/lib"
+
+                # Net-SNMP "clashes" with system-provided tools (but no header/lib)
+                # so explicit args are needed
+                checkFSobj="${HOMEBREW_PREFIX}/opt/net-snmp/lib/pkgconfig"
+                if [ -d "$checkFSobj" -a ! -e "${HOMEBREW_PREFIX}/lib/pkgconfig/netsnmp.pc" ] ; then
+                    echo "Homebrew: export pkg-config location for Net-SNMP"
+                    SYS_PKG_CONFIG_PATH="$SYS_PKG_CONFIG_PATH:$checkFSobj"
+                    #echo "Homebrew: export flags for Net-SNMP"
+                    #CONFIG_OPTS+=("--with-snmp-includes=-isystem ${HOMEBREW_PREFIX}/opt/net-snmp/include -I${HOMEBREW_PREFIX}/opt/net-snmp/include")
+                    #CONFIG_OPTS+=("--with-snmp-libs=-L${HOMEBREW_PREFIX}/opt/net-snmp/lib")
+                fi
+
+                if [ -d "${HOMEBREW_PREFIX}/opt/net-snmp/include" -a -d "${HOMEBREW_PREFIX}/include/openssl" ]; then
+                    # TODO? Check netsnmp.pc for Libs.private with
+                    #   -L/opt/homebrew/opt/openssl@1.1/lib
+                    # or
+                    #   -L/usr/local/opt/openssl@3/lib
+                    # among other options to derive the exact version
+                    # it wants, and serve that include path here
+                    echo "Homebrew: export configure options for Net-SNMP with default OpenSSL headers (too intimate on Homebrew)"
+                    CONFIG_OPTS+=("--with-snmp-includes=-isystem ${HOMEBREW_PREFIX}/opt/net-snmp/include -I${HOMEBREW_PREFIX}/opt/net-snmp/include -isystem ${HOMEBREW_PREFIX}/include -I${HOMEBREW_PREFIX}/include")
+                    CONFIG_OPTS+=("--with-snmp-libs=-L${HOMEBREW_PREFIX}/opt/net-snmp/lib -lnetsnmp")
+                fi
+
+                # A bit hackish to check this outside `configure`, but...
+                if [ -s "${HOMEBREW_PREFIX-}/include/ltdl.h" ] ; then
+                    echo "Homebrew: export flags for LibLTDL"
+                    # The m4 script clear default CFLAGS/LIBS so benefit from new ones
+                    CONFIG_OPTS+=("--with-libltdl-includes=-isystem ${HOMEBREW_PREFIX}/include -I${HOMEBREW_PREFIX}/include")
+                    CONFIG_OPTS+=("--with-libltdl-libs=-L${HOMEBREW_PREFIX}/lib -lltdl")
+                fi
+
+                if [ -z "${XML_CATALOG_FILES-}" ] ; then
+                    checkFSobj="${HOMEBREW_PREFIX}/etc/xml/catalog"
+                    if [ -e "$checkFSobj" ] ; then
+                        echo "Homebrew: export XML_CATALOG_FILES='$checkFSobj' for asciidoc et al"
+                        XML_CATALOG_FILES="$checkFSobj"
+                        export XML_CATALOG_FILES
+                    fi
+                fi
+            else
+                echo "WARNING: It seems you are building on MacOS, but HOMEBREW_PREFIX is not set or valid."
+                echo 'If you do use this build system, try running   eval "$(brew shellenv)"'
+                echo "in your terminal or shell profile, it can help with auto-detection of some features!"
+            fi
+            ;;
     esac
     if [ -n "$SYS_PKG_CONFIG_PATH" ] ; then
         if [ -n "$PKG_CONFIG_PATH" ] ; then
@@ -1032,6 +1142,14 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
         CONFIG_OPTS+=("PKG_CONFIG_PATH=${DEFAULT_PKG_CONFIG_PATH}")
     fi
 
+    # Note: Potentially there can be spaces in entries for multiple
+    # *FLAGS here; this should be okay as long as entry expands to
+    # one token when calling shell (may not be the case for distcheck)
+    CONFIG_OPTS+=("CFLAGS=-I${BUILD_PREFIX}/include ${CFLAGS}")
+    CONFIG_OPTS+=("CPPFLAGS=-I${BUILD_PREFIX}/include ${CPPFLAGS}")
+    CONFIG_OPTS+=("CXXFLAGS=-I${BUILD_PREFIX}/include ${CXXFLAGS}")
+    CONFIG_OPTS+=("LDFLAGS=-L${BUILD_PREFIX}/lib ${LDFLAGS}")
+
     CONFIG_OPTS+=("--enable-keep_nut_report_feature")
     CONFIG_OPTS+=("--prefix=${BUILD_PREFIX}")
     CONFIG_OPTS+=("--sysconfdir=${BUILD_PREFIX}/etc/nut")
@@ -1215,7 +1333,11 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
                     CONFIG_OPTS+=("--with-cgi=auto")
                 fi
             else
-                CONFIG_OPTS+=("--with-cgi=auto")
+                if [ "${CANBUILD_LIBGD_CGI-}" = "no" ] ; then
+                    CONFIG_OPTS+=("--without-cgi")
+                else
+                    CONFIG_OPTS+=("--with-cgi=auto")
+                fi
             fi
             ;;
         "default-alldrv:no-distcheck")
@@ -1359,38 +1481,13 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
         CONFIG_OPTS+=("--with-debuginfo=${BUILD_DEBUGINFO}")
     fi
 
-    # Note: modern auto(re)conf requires pkg-config to generate the configure
-    # script, so to stage the situation of building without one (as if on an
-    # older system) we have to remove it when we already have the script.
-    # This matches the use-case of distro-building from release tarballs that
-    # include all needed pre-generated files to rely less on OS facilities.
-    if [ -s Makefile ]; then
-        if [ -n "`find "${SCRIPTDIR}" -name configure.ac -newer "${CI_BUILDDIR}"/configure`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name '*.m4' -newer "${CI_BUILDDIR}"/configure`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.in -newer "${CI_BUILDDIR}"/Makefile`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile.in`" ] \
-        ; then
-            # Avoid reconfiguring for the sake of distclean
-            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because recipes changed"
-            rm -f "${CI_BUILDDIR}"/Makefile "${CI_BUILDDIR}"/configure
-        fi
-    fi
-
-    # When itertating configure.ac or m4 sources, we can end up with an
-    # existing but useless scropt file - nuke it and restart from scratch!
-    if [ -s "${CI_BUILDDIR}"/configure ] ; then
-        if ! sh -n "${CI_BUILDDIR}"/configure 2>/dev/null ; then
-            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because current configure script syntax is broken"
-            rm -f "${CI_BUILDDIR}"/Makefile "${CI_BUILDDIR}"/configure
-        fi
-    fi
+    consider_cleanup_shortcut
 
     if [ -s Makefile ]; then
         # Let initial clean-up be at default verbosity
 
         # Handle Ctrl+C with helpful suggestions:
-        trap 'echo "!!! If clean-up looped remaking the configure script for maintainer-clean, try to:"; echo "    rm -f Makefile configure ; $0 $SCRIPT_ARGS"' 2
+        trap 'echo "!!! If clean-up looped remaking the configure script for maintainer-clean, try to:"; echo "    rm -f Makefile configure include/config.h* ; $0 $SCRIPT_ARGS"' 2
 
         echo "=== Starting initial clean-up (from old build products)"
         case "$MAKE_FLAGS $MAKE_FLAGS_CLEAN" in
@@ -1430,7 +1527,11 @@ default|default-alldrv|default-alldrv:no-distcheck|default-all-errors|default-sp
             # e.g. distcheck-light, distcheck-valgrind, cppcheck, maybe
             # others later, as defined in Makefile.am:
             BUILD_TGT="`echo "$BUILD_TYPE" | sed 's,^default-tgt:,,'`"
-            echo "`date`: Starting the sequential build attempt for singular target $BUILD_TGT..."
+            if [ -n "${PARMAKE_FLAGS}" ]; then
+                echo "`date`: Starting the parallel build attempt for singular target $BUILD_TGT..."
+            else
+                echo "`date`: Starting the sequential build attempt for singular target $BUILD_TGT..."
+            fi
 
             # Note: Makefile.am already sets some default DISTCHECK_CONFIGURE_FLAGS
             # that include DISTCHECK_FLAGS if provided
@@ -1981,27 +2082,8 @@ bindings)
     fi
 
     cd "${SCRIPTDIR}"
-    if [ -s Makefile ]; then
-        if [ -n "`find "${SCRIPTDIR}" -name configure.ac -newer "${CI_BUILDDIR}"/configure`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name '*.m4' -newer "${CI_BUILDDIR}"/configure`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.in -newer "${CI_BUILDDIR}"/Makefile`" ] \
-        || [ -n "`find "${SCRIPTDIR}" -name Makefile.am -newer "${CI_BUILDDIR}"/Makefile.in`" ] \
-        ; then
-            # Avoid reconfiguring for the sake of distclean
-            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because recipes changed"
-            rm -f "${CI_BUILDDIR}"/Makefile "${CI_BUILDDIR}"/configure
-        fi
-    fi
 
-    # When itertating configure.ac or m4 sources, we can end up with an
-    # existing but useless scropt file - nuke it and restart from scratch!
-    if [ -s "${CI_BUILDDIR}"/configure ] ; then
-        if ! sh -n "${CI_BUILDDIR}"/configure 2>/dev/null ; then
-            echo "=== Starting initial clean-up (from old build products): TAKING SHORTCUT because current configure script syntax is broken"
-            rm -f "${CI_BUILDDIR}"/Makefile "${CI_BUILDDIR}"/configure
-        fi
-    fi
+    consider_cleanup_shortcut
 
     if [ -s Makefile ]; then
         # Help developers debug:
@@ -2042,11 +2124,28 @@ bindings)
         CONFIG_OPTS+=("--with-debuginfo=auto")
     fi
 
-    ${CONFIGURE_SCRIPT} "${CONFIG_OPTS[@]}"
+    if [ -n "${PYTHON-}" ]; then
+        # WARNING: Watch out for whitespaces, not handled here!
+        CONFIG_OPTS+=("--with-python=${PYTHON}")
+    fi
+
+    RES_CFG=0
+    ${CONFIGURE_SCRIPT} "${CONFIG_OPTS[@]}" \
+    || RES_CFG=$?
+    echo "$0: configure phase complete ($RES_CFG)" >&2
+    [ x"$RES_CFG" = x0 ] || exit $RES_CFG
 
     # NOTE: Currently parallel builds are expected to succeed (as far
     # as recipes are concerned), and the builds without a BUILD_TYPE
     # are aimed at developer iterations so not tweaking verbosity.
+    echo "Configuration finished, starting make" >&2
+    if [ -n "$PARMAKE_FLAGS" ]; then
+        echo "For parallel builds, '$PARMAKE_FLAGS' options would be used" >&2
+    fi
+    if [ -n "$MAKEFLAGS" ]; then
+        echo "Generally, MAKEFLAGS='$MAKEFLAGS' options would be passed" >&2
+    fi
+
     #$MAKE all || \
     $MAKE $PARMAKE_FLAGS all || exit
     if [ "${CI_SKIP_CHECK}" != true ] ; then $MAKE check || exit ; fi
diff --git a/clients/.gitignore b/clients/.gitignore
index 26183d14df..c422f84a7d 100644
--- a/clients/.gitignore
+++ b/clients/.gitignore
@@ -1,3 +1,4 @@
+/libupsclient-version.h
 /upsimage.cgi
 /upsset.cgi
 /upsstats.cgi
diff --git a/clients/Makefile.am b/clients/Makefile.am
index b873046cc0..bb5957984b 100644
--- a/clients/Makefile.am
+++ b/clients/Makefile.am
@@ -3,13 +3,14 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 EXTRA_DIST =
+CLEANFILES =
 
 # nutclient.cpp for some legacy reason (maybe initial detached development?)
 # optionally includes "common.h" with the NUT build setup - and this option
@@ -117,6 +118,31 @@ if HAVE_WINDOWS
   libupsclient_la_LDFLAGS += -no-undefined
 endif
 
+# ./clients/libupsclient.la samples (partial!) on...
+# Linux:
+#   # The name that we can dlopen(3).
+#   dlname='libupsclient.so.6'
+#   # Names of this library.
+#   library_names='libupsclient.so.6.0.1 libupsclient.so.6 libupsclient.so'
+#   # Directory that this library needs to be installed in:
+#   libdir='/usr/local/ups/lib'
+# WIN32:
+#   dlname='libupsclient-6.dll'
+#   library_names='libupsclient.dll.a'
+#   libdir='//lib'
+CLEANFILES += libupsclient-version.h
+libupsclient-version.h: libupsclient.la
+	@dlname_filter() { sed -e 's/^[^=]*=//' -e 's/^"\(.*\)"$$/\1/' -e 's/^'"'"'\(.*\)'"'"'$$/\1/' ; }; \
+	 SOFILE_LIBUPSCLIENT="`grep -E '^dlname' '$?' | dlname_filter`" \
+	 || SOFILE_LIBUPSCLIENT="" ; \
+	 if [ x"$${SOFILE_LIBUPSCLIENT-}" = x ] ; then \
+	    printf "#ifdef SOFILE_LIBUPSCLIENT\n# undef SOFILE_LIBUPSCLIENT\n#endif\n\n" ; \
+	    printf "#ifdef SOPATH_LIBUPSCLIENT\n# undef SOPATH_LIBUPSCLIENT\n#endif\n\n" ; \
+	 else \
+	    printf "#ifndef SOFILE_LIBUPSCLIENT\n# define SOFILE_LIBUPSCLIENT \"%s\"\n#endif\n\n" "$${SOFILE_LIBUPSCLIENT}" ; \
+	    printf "#ifndef SOPATH_LIBUPSCLIENT\n# define SOPATH_LIBUPSCLIENT \"%s/%s\"\n#endif\n\n" "@LIBDIR@" "$${SOFILE_LIBUPSCLIENT}" ; \
+	 fi > "$@"
+
 if HAVE_CXX11
 # libnutclient version information and build
 libnutclient_la_SOURCES = nutclient.h nutclient.cpp
diff --git a/clients/nutclient.cpp b/clients/nutclient.cpp
index 63ec2ae903..d873e387c0 100644
--- a/clients/nutclient.cpp
+++ b/clients/nutclient.cpp
@@ -1367,6 +1367,31 @@ std::vector<std::string> TcpClient::explode(const std::string& str, size_t begin
 			}
 			state = QUOTED_STRING;
 			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 		}
 	}
 
diff --git a/clients/nutclient.h b/clients/nutclient.h
index 8047e26ced..19dbdcfde4 100644
--- a/clients/nutclient.h
+++ b/clients/nutclient.h
@@ -18,7 +18,7 @@
 */
 
 #ifndef NUTCLIENT_HPP_SEEN
-#define NUTCLIENT_HPP_SEEN
+#define NUTCLIENT_HPP_SEEN 1
 
 /* Begin of C++ nutclient library declaration */
 #ifdef __cplusplus
diff --git a/clients/nutclientmem.h b/clients/nutclientmem.h
index 6363262681..8584a9ca45 100644
--- a/clients/nutclientmem.h
+++ b/clients/nutclientmem.h
@@ -18,7 +18,7 @@
 */
 
 #ifndef NUTCLIENTMEM_HPP_SEEN
-#define NUTCLIENTMEM_HPP_SEEN
+#define NUTCLIENTMEM_HPP_SEEN 1
 
 /* Begin of C++ nutclient library declaration */
 #ifdef __cplusplus
@@ -117,4 +117,4 @@ NUTCLIENT_MEM_t nutclient_mem_create_client();
 #endif /* __cplusplus */
 /* End of C nutclient library declaration */
 
-#endif	/* NUTCLIENTMOCK_HPP_SEEN */
+#endif	/* NUTCLIENTMEM_HPP_SEEN */
diff --git a/clients/upsc.c b/clients/upsc.c
index 71715f4731..d99d18085a 100644
--- a/clients/upsc.c
+++ b/clients/upsc.c
@@ -2,6 +2,7 @@
 
    Copyright (C) 1999  Russell Kroll <rkroll@exploits.org>
    Copyright (C) 2012  Arnaud Quette <arnaud.quette@free.fr>
+   Copyright (C) 2020-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -35,15 +36,14 @@ static UPSCONN_t	*ups = NULL;
 
 static void usage(const char *prog)
 {
-	printf("Network UPS Tools upsc %s\n\n", UPS_VERSION);
+	print_banner_once(prog, 2);
+	printf("NUT read-only client program to display UPS variables.\n");
 
-	printf("usage: %s -l | -L [<hostname>[:port]]\n", prog);
+	printf("\nusage: %s -l | -L [<hostname>[:port]]\n", prog);
 	printf("       %s <ups> [<variable>]\n", prog);
 	printf("       %s -c <ups>\n", prog);
 
-	printf("\nDemo program to display UPS variables.\n\n");
-
-	printf("First form (lists UPSes):\n");
+	printf("\nFirst form (lists UPSes):\n");
 	printf("  -l         - lists each UPS on <hostname>, one per line.\n");
 	printf("  -L         - lists each UPS followed by its description (from ups.conf).\n");
 	printf("               Default hostname: localhost\n");
@@ -217,10 +217,22 @@ static void clean_exit(void)
 
 int main(int argc, char **argv)
 {
-	int	i;
+	int	i = 0;
 	uint16_t	port;
 	int	varlist = 0, clientlist = 0, verbose = 0;
 	const char	*prog = xbasename(argv[0]);
+	char	*s = NULL;
+
+	/* NOTE: Caller must `export NUT_DEBUG_LEVEL` to see debugs for upsc
+	 * and NUT methods called from it. This line aims to just initialize
+	 * the subsystem, and set initial timestamp. Debugging the client is
+	 * primarily of use to developers, so is not exposed via `-D` args.
+	 */
+	s = getenv("NUT_DEBUG_LEVEL");
+	if (s && str_to_int(s, &i, 10) && i > 0) {
+		nut_debug_level = i;
+	}
+	upsdebugx(1, "Starting NUT client: %s", prog);
 
 	while ((i = getopt(argc, argv, "+hlLcV")) != -1) {
 
@@ -238,12 +250,11 @@ int main(int argc, char **argv)
 			break;
 
 		case 'V':
+			/* just show the version and optional
+			 * CONFIG_FLAGS banner if available */
+			print_banner_once(prog, 1);
 			nut_report_config_flags();
-
-			fatalx(EXIT_SUCCESS, "Network UPS Tools upsc %s", UPS_VERSION);
-#ifndef HAVE___ATTRIBUTE__NORETURN
-			exit(EXIT_SUCCESS);	/* Should not get here in practice, but compiler is afraid we can fall through */
-#endif
+			exit(EXIT_SUCCESS);
 
 		case 'h':
 		default:
@@ -267,6 +278,8 @@ int main(int argc, char **argv)
 			fatalx(EXIT_FAILURE, "Error: invalid UPS definition.\nRequired format: upsname[@hostname[:port]]");
 		}
 	}
+	upsdebugx(1, "upsname='%s' hostname='%s' port='%" PRIu16 "'",
+		NUT_STRARG(upsname), NUT_STRARG(hostname), port);
 
 	ups = xmalloc(sizeof(*ups));
 
@@ -275,18 +288,22 @@ int main(int argc, char **argv)
 	}
 
 	if (varlist) {
+		upsdebugx(1, "Calling list_upses()");
 		list_upses(verbose);
 		exit(EXIT_SUCCESS);
 	}
 
 	if (clientlist) {
+		upsdebugx(1, "Calling list_clients()");
 		list_clients(upsname);
 		exit(EXIT_SUCCESS);
 	}
 
 	if (argc > 1) {
+		upsdebugx(1, "Calling printvar(%s)", argv[1]);
 		printvar(argv[1]);
 	} else {
+		upsdebugx(1, "Calling list_vars()");
 		list_vars();
 	}
 
diff --git a/clients/upsclient.c b/clients/upsclient.c
index 74290cd26f..d6a3d6ff59 100644
--- a/clients/upsclient.c
+++ b/clients/upsclient.c
@@ -3,6 +3,7 @@
    Copyright (C)
 	2002	Russell Kroll <rkroll@exploits.org>
 	2008	Arjen de Korte <adkorte-guest@alioth.debian.org>
+	2020 - 2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -61,25 +62,25 @@
 
 /* WA for Solaris/i386 bug: non-blocking connect sets errno to ENOENT */
 #if (defined NUT_PLATFORM_SOLARIS)
-	#define SOLARIS_i386_NBCONNECT_ENOENT(status) ( (!strcmp("i386", CPU_TYPE)) ? (ENOENT == (status)) : 0 )
+#	define SOLARIS_i386_NBCONNECT_ENOENT(status) ( (!strcmp("i386", CPU_TYPE)) ? (ENOENT == (status)) : 0 )
 #else
-	#define SOLARIS_i386_NBCONNECT_ENOENT(status) (0)
+#	define SOLARIS_i386_NBCONNECT_ENOENT(status) (0)
 #endif  /* end of Solaris/i386 WA for non-blocking connect */
 
 /* WA for AIX bug: non-blocking connect sets errno to 0 */
 #if (defined NUT_PLATFORM_AIX)
-	#define AIX_NBCONNECT_0(status) (0 == (status))
+#	define AIX_NBCONNECT_0(status) (0 == (status))
 #else
-	#define AIX_NBCONNECT_0(status) (0)
+#	define AIX_NBCONNECT_0(status) (0)
 #endif  /* end of AIX WA for non-blocking connect */
 
 #ifdef WITH_NSS
-	#include <prerror.h>
-	#include <prinit.h>
-	#include <pk11func.h>
-	#include <prtypes.h>
-	#include <ssl.h>
-	#include <private/pprio.h>
+#	include <prerror.h>
+#	include <prinit.h>
+#	include <pk11func.h>
+#	include <prtypes.h>
+#	include <ssl.h>
+#	include <private/pprio.h>
 #endif /* WITH_NSS */
 
 #define UPSCLIENT_MAGIC 0x19980308
@@ -619,6 +620,9 @@ const char *upscli_strerror(UPSCONN_t *ups)
 			upscli_errlist[ups->upserror].str,
 			ups->pc_ctx.errmsg);
 		return ups->errbuf;
+
+	default:
+		break;
 	}
 
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_NONLITERAL
@@ -1024,6 +1028,7 @@ int upscli_tryconnect(UPSCONN_t *ups, const char *host, uint16_t port, int flags
 	ups->fd = -1;
 
 	if (!host) {
+		upslogx(LOG_WARNING, "%s: Host not specified", __func__);
 		ups->upserror = UPSCLI_ERR_NOSUCHHOST;
 		return -1;
 	}
@@ -1049,6 +1054,7 @@ int upscli_tryconnect(UPSCONN_t *ups, const char *host, uint16_t port, int flags
 		case EAI_AGAIN:
 			continue;
 		case EAI_NONAME:
+			upslogx(LOG_WARNING, "%s: Host not found: '%s'", __func__, NUT_STRARG(host));
 			ups->upserror = UPSCLI_ERR_NOSUCHHOST;
 			return -1;
 		case EAI_MEMORY:
@@ -1057,6 +1063,8 @@ int upscli_tryconnect(UPSCONN_t *ups, const char *host, uint16_t port, int flags
 		case EAI_SYSTEM:
 			ups->syserrno = errno;
 			break;
+		default:
+			break;
 		}
 
 		ups->upserror = UPSCLI_ERR_UNKNOWN;
@@ -1207,7 +1215,7 @@ int upscli_tryconnect(UPSCONN_t *ups, const char *host, uint16_t port, int flags
 		} else if (tryssl && ret == 0) {
 			if (certverify != 0) {
 				upslogx(LOG_NOTICE, "Can not connect to NUT server %s in SSL and "
-				"certificate is needed, disconnect", host);
+					"certificate is needed, disconnect", host);
 				upscli_disconnect(ups);
 				return -1;
 			}
@@ -1686,7 +1694,21 @@ int upscli_splitaddr(const char *buf, char **hostname, uint16_t *port)
 		return -1;
 	}
 
+	s = strchr(tmp, '@');
+
+	/* someone passed a "@hostname" string? */
+	if (s) {
+		fprintf(stderr, "upscli_splitaddr: wrong call? "
+			"Got upsname@hostname[:port] string where "
+			"only hostname[:port] was expected: %s\n", buf);
+		/* let it pass, but probably fail later */
+	}
+
 	if (*tmp == '[') {
+		/* NOTE: Brackets are required for colon-separated IPv6
+		 * addresses, to differentiate from a port number. For
+		 * example, `[1234:5678]:3493` would seem right.
+		 */
 		if (strchr(tmp, ']') == NULL) {
 			fprintf(stderr, "upscli_splitaddr: missing closing bracket in [domain literal]\n");
 			return -1;
diff --git a/clients/upsclient.h b/clients/upsclient.h
index c79be96cfd..c359905882 100644
--- a/clients/upsclient.h
+++ b/clients/upsclient.h
@@ -18,27 +18,27 @@
 */
 
 #ifndef UPSCLIENT_H_SEEN
-#define UPSCLIENT_H_SEEN
+#define UPSCLIENT_H_SEEN 1
 
 #ifdef WITH_OPENSSL
-	#include <openssl/err.h>
-	#include <openssl/ssl.h>
+#	include <openssl/err.h>
+#	include <openssl/ssl.h>
 #elif defined(WITH_NSS) /* WITH_OPENSSL */
-	#include <nss.h>
-	#include <ssl.h>
+#	include <nss.h>
+#	include <ssl.h>
 #endif  /* WITH_OPENSSL | WITH_NSS */
 
 /* Not including nut_stdint.h because this is part of end-user API */
 #if defined HAVE_INTTYPES_H
-	#include <inttypes.h>
+#	include <inttypes.h>
 #endif
 
 #if defined HAVE_STDINT_H
-	#include <stdint.h>
+#	include <stdint.h>
 #endif
 
 #if defined HAVE_LIMITS_H
-	#include <limits.h>
+#	include <limits.h>
 #endif
 
 /* Not including NUT timehead.h because this is part of end-user API */
@@ -53,6 +53,10 @@
 # endif
 #endif
 
+#if defined HAVE_SYS_TYPES_H
+# include <sys/types.h>
+#endif
+
 #ifdef __cplusplus
 /* *INDENT-OFF* */
 extern "C" {
diff --git a/clients/upscmd.c b/clients/upscmd.c
index 4d71ebce2f..868009bf53 100644
--- a/clients/upscmd.c
+++ b/clients/upscmd.c
@@ -47,11 +47,12 @@ struct list_t {
 
 static void usage(const char *prog)
 {
-	printf("Network UPS Tools upscmd %s\n\n", UPS_VERSION);
-	printf("usage: %s [-h]\n", prog);
+	print_banner_once(prog, 2);
+	printf("NUT administration client program to initiate instant commands on UPS hardware.\n");
+
+	printf("\nusage: %s [-h]\n", prog);
 	printf("       %s [-l <ups>]\n", prog);
 	printf("       %s [-u <username>] [-p <password>] [-w] [-t <timeout>] <ups> <command> [<value>]\n\n", prog);
-	printf("Administration program to initiate instant commands on UPS hardware.\n");
 	printf("\n");
 	printf("  -h		display this help text\n");
 	printf("  -V		display the version of this software\n");
@@ -312,12 +313,11 @@ int main(int argc, char **argv)
 			break;
 
 		case 'V':
+			/* just show the version and optional
+			 * CONFIG_FLAGS banner if available */
+			print_banner_once(prog, 1);
 			nut_report_config_flags();
-
-			fatalx(EXIT_SUCCESS, "Network UPS Tools upscmd %s", UPS_VERSION);
-#ifndef HAVE___ATTRIBUTE__NORETURN
-			exit(EXIT_SUCCESS);	/* Should not get here in practice, but compiler is afraid we can fall through */
-#endif
+			exit(EXIT_SUCCESS);
 
 		case 'h':
 		default:
diff --git a/clients/upslog.c b/clients/upslog.c
index 502f6299e9..f1d36b9fcc 100644
--- a/clients/upslog.c
+++ b/clients/upslog.c
@@ -144,7 +144,8 @@ static void help(const char *prog)
 
 static void help(const char *prog)
 {
-	printf("UPS status logger.\n");
+	print_banner_once(prog, 2);
+	printf("NUT read-only client program - UPS status logger.\n");
 
 	printf("\nusage: %s [OPTIONS]\n", prog);
 	printf("\n");
@@ -439,7 +440,7 @@ int main(int argc, char **argv)
 	logformat = DEFAULT_LOGFORMAT;
 	user = RUN_AS_USER;
 
-	printf("Network UPS Tools %s %s\n", prog, UPS_VERSION);
+	print_banner_once(prog, 0);
 
 	while ((i = getopt(argc, argv, "+hs:l:i:f:u:Vp:FBm:")) != -1) {
 		switch(i) {
@@ -505,6 +506,9 @@ int main(int argc, char **argv)
 				break;
 
 			case 'V':
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(prog, 1);
 				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
 
@@ -519,6 +523,12 @@ int main(int argc, char **argv)
 			case 'B':
 				foreground = 0;
 				break;
+
+			default:
+				fatalx(EXIT_FAILURE,
+					"Error: unknown option -%c. Try -h for help.",
+					(char)i);
+
 		}
 	}
 
diff --git a/clients/upsmon.c b/clients/upsmon.c
index 1b4af7cfb4..ed9a630722 100644
--- a/clients/upsmon.c
+++ b/clients/upsmon.c
@@ -3,7 +3,7 @@
    Copyright (C)
      1998  Russell Kroll <rkroll@exploits.org>
      2012  Arnaud Quette <arnaud.quette.free.fr>
-     2020-2023  Jim Klimov <jimklimov+nut@gmail.com>
+     2020-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -24,12 +24,12 @@
 
 #include <sys/stat.h>
 #ifndef WIN32
-#include <sys/wait.h>
-#include <sys/socket.h>
-#include <unistd.h>
-#include <fcntl.h>
+# include <sys/wait.h>
+# include <sys/socket.h>
+# include <unistd.h>
+# include <fcntl.h>
 #else
-#include <wincompat.h>
+# include <wincompat.h>
 #endif
 
 #include "nut_stdint.h"
@@ -39,7 +39,7 @@
 #include "timehead.h"
 
 #ifdef HAVE_STDARG_H
-#include <stdarg.h>
+# include <stdarg.h>
 #endif
 
 static	char	*shutdowncmd = NULL, *notifycmd = NULL;
@@ -86,6 +86,20 @@ static	int	pollfail_log_throttle_max = -1;
 	 */
 static	int	offdurationtime = 30;
 
+	/* Normally we raise alarms for immediate shutdown for consumers
+	 * of an UPS known to be on battery (OB) and achieving the low
+	 * battery status (LB), if that is their last remaining power
+	 * source to satisfy their MINSUPPLIES setting.
+	 * In some cases, users may want to delay raising the alarm
+	 * (using the OBLBDURATION option) at their discretion and risk
+	 * of an ungraceful shutdown.
+	 * UPS state polling frequency will be the minimum of this delay
+	 * and POLLFREQALERT (as normally applied for "OB" devices) when
+	 * this situation is in place.
+	 * Non-positive values are currently treated as 0 (immediate FSD).
+	 */
+static	int	oblbdurationtime = 0;
+
 	/* secondary hosts are given 15 sec by default to logout from upsd */
 static	int	hostsync = 15;
 
@@ -138,7 +152,13 @@ static	sigset_t nut_upsmon_sigmask;
 
 #ifdef HAVE_SYSTEMD
 # define SERVICE_UNIT_NAME "nut-monitor.service"
-#endif
+#endif	/* HAVE_SYSTEMD */
+
+/* If we successfully use Inhibit() to be notified about
+ * the OS going to sleep, this is the messenger variable:
+ */
+static TYPE_FD	sleep_inhibitor_fd = ERROR_FD;
+static int	sleep_inhibitor_status = -2;
 
 /* Users can pass a -D[...] option to enable debugging.
  * For the service tracing purposes, also the upsmon.conf
@@ -192,7 +212,7 @@ static void wall(const char *text)
 	fprintf(wf, "%s\n", text);
 	pclose(wf);
 #else
-	#define MESSAGE_CMD "message.exe"
+#	define MESSAGE_CMD "message.exe"
 	char * command;
 
 	/* first +1 is for the space between message and text
@@ -325,6 +345,8 @@ static void notify(const char *notice, int flags, const char *ntype,
 		}
 	}
 
+	upsdebugx(6, "%s (child): exiting after notifications", __func__);
+
 	exit(EXIT_SUCCESS);
 #else
 	async_notify_t * data;
@@ -379,6 +401,10 @@ static void do_notify(const utype_t *ups, int ntype)
 #endif
 			notify(msg, notifylist[i].flags, notifylist[i].name,
 				upsname);
+
+			upsdebugx(3, "%s: ntype 0x%04x (%s) finished",
+				__func__, ntype, notifylist[i].name);
+
 			return;
 		}
 	}
@@ -1062,6 +1088,9 @@ static int is_ups_critical(utype_t *ups)
 	if (flag_isset(ups->status, ST_FSD))
 		return 1;
 
+	/* Used in a number of clauses below */
+	time(&now);
+
 	if (ups->commstate == 0) {
 		if (flag_isset(ups->status, ST_CAL)) {
 			upslogx(LOG_WARNING,
@@ -1090,11 +1119,17 @@ static int is_ups_critical(utype_t *ups)
 		}
 
 		if (ups->linestate == 0) {
-			upslogx(LOG_WARNING,
+			/* Just a message for post-mortem troubleshooting:
+			 * no flag flips, no return values issued just here
+			 * (note the message is likely to appear on every
+			 * cycle when the communications are down, to help
+			 * track when this was the case; no log throttling).
+			 */
+			upsdebugx(1,
 				"UPS [%s] was last known to be not fully online "
-				"and currently is not communicating, assuming dead",
+				"and currently is not communicating, just so you "
+				"know (waiting for DEADTIME to elapse)",
 				ups->sys);
-			return 1;
 		}
 	}
 
@@ -1111,8 +1146,23 @@ static int is_ups_critical(utype_t *ups)
 	/* not OB or not LB = not critical yet */
 	if ((!flag_isset(ups->status, ST_ONBATT))
 	|| (!flag_isset(ups->status, ST_LOWBATT))
-	)
+	) {
+		if (ups->oblbsince > 0) {
+			upslogx(LOG_WARNING,
+				"%s: seems that UPS [%s] returned from OB+LB "
+				"state now after spending %" PRIiMAX
+				" seconds in it",
+				__func__, ups->upsname,
+				(intmax_t)(now - ups->oblbsince));
+			ups->oblbsince = 0;
+
+			if (flag_isset(ups->status, ST_ONBATT))
+				sleepval = pollfreqalert;
+			else
+				sleepval = pollfreq;
+		}
 		return 0;
+	}
 
 	/* must be OB+LB now */
 
@@ -1129,17 +1179,90 @@ static int is_ups_critical(utype_t *ups)
 		return 0;
 	}
 
-	/* if we're a primary, declare it critical so we set FSD on it */
-	if (flag_isset(ups->status, ST_PRIMARY))
-		return 1;
+	if (oblbdurationtime > 0) {
+		/* User configured this upsmon instance to delay
+		 * issuing or processing FSD alerts */
+		if (ups->oblbsince < 1 && now > 0) {
+			/* We would bump polling frequency if needed,
+			 * to check the UPS state as soon as needed
+			 * to see if this requested OB+LB duration
+			 * has elapsed (every 1 sec in extreme case).
+			 * Using GCD algorithm inspired by
+			 *   https://www.programiz.com/c-programming/examples/hcf-gcd
+			 */
+			int n1 = (pollfreqalert > 0) ? pollfreqalert : 1;
+			int n2 = (oblbdurationtime > 0) ? oblbdurationtime : 1;
+
+			/* Find GCD: */
+			while (n1 != n2) {
+				if (n1 > n2)
+					n1 -= n2;
+				else
+					n2 -= n1;
+			}
+			sleepval = (n1 > 0) ? n1 : 1;
 
-	/* must be a secondary now */
+			upslogx(LOG_WARNING,
+				"%s: seems that UPS [%s] is OB+LB now, "
+				"but OBLBDURATION=%d - not declaring "
+				"a critical state just now, but will "
+				"bump the polling rate to %d (from "
+				"POLLFREQALERT=%d) and wait to see "
+				"if this situation dissipates soon",
+				__func__, ups->upsname,
+				oblbdurationtime,
+				sleepval,
+				pollfreqalert);
+
+			if (!flag_isset(ups->status, ST_PRIMARY)
+			&& hostsync > oblbdurationtime
+			) {
+				upslogx(LOG_WARNING,
+					"%s: HOSTSYNC=%d exceeds OBLBDURATION "
+					"and would be effectively ignored on "
+					"this secondary upsmon client system",
+					__func__, hostsync);
+			}
 
-	/* FSD isn't set, so the primary hasn't seen it yet */
+			ups->oblbsince = now;
 
-	time(&now);
+			return 0;
+		}
 
-	/* give the primary up to HOSTSYNC seconds before shutting down */
+		/* Already looping in OB LB duration? */
+		if (now > 0 && (now - ups->oblbsince < oblbdurationtime)) {
+			upslogx(LOG_WARNING,
+				"%s: seems that UPS [%s] is still "
+				"OB+LB for %" PRIiMAX " sec out of %d delay",
+				__func__, ups->upsname,
+				(intmax_t)(now - ups->oblbsince),
+				oblbdurationtime);
+			return 0;
+		}
+
+		upslogx(LOG_WARNING,
+			"%s: seems that UPS [%s] is still "
+			"OB+LB for %" PRIiMAX " sec out of %d delay - "
+			"proceeding with shutdown alerts",
+			__func__, ups->upsname,
+			(intmax_t)(now - ups->oblbsince),
+			oblbdurationtime);
+
+		/* Timer expired, fall through to raise FSD on this primary
+		 * or handle it on the secondary */
+	}
+
+	/* if we're a primary, declare it critical so we set FSD on it */
+	if (flag_isset(ups->status, ST_PRIMARY)) {
+		return 1;
+	}
+
+	/* We must be a secondary now, in OB+LB situation, and
+	 * FSD isn't set - so the primary hasn't seen it yet.
+	 * Give the primary up to HOSTSYNC seconds to report it
+	 * before commencing to shut down this secondary system
+	 * anyway.
+	 */
 	if ((now - ups->lastnoncrit) > hostsync) {
 		upslogx(LOG_WARNING, "Giving up on the primary for UPS [%s] "
 			"after %d sec since last comms",
@@ -1147,7 +1270,8 @@ static int is_ups_critical(utype_t *ups)
 		return 1;
 	}
 
-	/* there's still time left, maybe OB+LB will go away next time we look? */
+	/* secondary: there's still time left, maybe OB+LB will go away next
+	 * time we look? */
 	return 0;
 }
 
@@ -1492,22 +1616,28 @@ static void addups(int reloading, const char *sys, const char *pvs,
 	else
 		firstups = tmp;
 
-	if (tmp->pv)
-		upslogx(LOG_INFO, "UPS: %s (%s) (power value %d)", tmp->sys,
-			flag_isset(tmp->status, ST_PRIMARY) ? "primary" : "secondary",
-			tmp->pv);
-	else
-		upslogx(LOG_INFO, "UPS: %s (monitoring only)", tmp->sys);
+	/* Negative debug value may be set by help() to be really quiet */
+	if (nut_debug_level > -1) {
+		if (tmp->pv)
+			upslogx(LOG_INFO, "UPS: %s (%s) (power value %d)", tmp->sys,
+				flag_isset(tmp->status, ST_PRIMARY) ? "primary" : "secondary",
+				tmp->pv);
+		else
+			upslogx(LOG_INFO, "UPS: %s (monitoring only)", tmp->sys);
+	}
 
 	tmp->upsname = tmp->hostname = NULL;
 
 	if (upscli_splitname(tmp->sys, &tmp->upsname, &tmp->hostname,
-		&tmp->port) != 0) {
-		upslogx(LOG_ERR, "Error: unable to split UPS name [%s]",
-			tmp->sys);
+		&tmp->port) != 0
+	) {
+		if (nut_debug_level > -1) {
+			upslogx(LOG_ERR, "Error: unable to split UPS name [%s]",
+				tmp->sys);
+		}
 	}
 
-	if (!tmp->upsname)
+	if (!tmp->upsname && nut_debug_level > -1)
 		upslogx(LOG_WARNING, "Warning: UPS [%s]: no upsname set!",
 			tmp->sys);
 }
@@ -1587,8 +1717,10 @@ static void checkmode(char *cfgentry, char *oldvalue, char *newvalue,
 	if (use_pipe == 0)
 		return;
 
-	/* it's ok if we're not reloading yet */
-	if (reloading == 0)
+	/* it's ok if we're not reloading yet
+	 * or "almost-fake" loading to show help()
+	 */
+	if (reloading < 1)
 		return;
 
 	/* also nothing to do if it didn't change */
@@ -1652,7 +1784,7 @@ static int parse_conf_arg(size_t numargs, char **arg)
 		powerdownflag = filter_path(arg[1]);
 #endif
 
-		if (!reload_flag)
+		if (reload_flag == 0)
 			upslogx(LOG_INFO, "Using power down flag file %s",
 				arg[1]);
 
@@ -1705,6 +1837,14 @@ static int parse_conf_arg(size_t numargs, char **arg)
 		return 1;
 	}
 
+	/* OBLBDURATION <num> */
+	if (!strcmp(arg[0], "OBLBDURATION")) {
+		oblbdurationtime = atoi(arg[1]);
+		if (oblbdurationtime < 1)
+			oblbdurationtime = 0;
+		return 1;
+	}
+
 	/* HOSTSYNC <num> */
 	if (!strcmp(arg[0], "HOSTSYNC")) {
 		hostsync = atoi(arg[1]);
@@ -1854,6 +1994,10 @@ static void loadconfig(void)
 	PCONF_CTX_t	ctx;
 	int	numerrors = 0;
 
+	upsdebugx(1, "%s: %s %s", __func__,
+		(reload_flag == 1) ? "Reloading" : "Loading",
+		configfile);
+
 	pconf_init(&ctx, upsmon_err);
 
 	if (!pconf_file_begin(&ctx, configfile)) {
@@ -1864,6 +2008,12 @@ static void loadconfig(void)
 			return;
 		}
 
+		if (reload_flag == -1) {
+			/* For help() */
+			upsdebugx(1, "Load failed: %s", ctx.errmsg);
+			return;
+		}
+
 		fatalx(EXIT_FAILURE, "%s", ctx.errmsg);
 	}
 
@@ -1930,11 +2080,14 @@ static void loadconfig(void)
 				nut_debug_level_global);
 			nut_debug_level = nut_debug_level_global;
 		} else {
-			/* DEBUG_MIN is absent or commented-away in ups.conf */
-			upslogx(LOG_INFO,
-				"Applying debug level %d from "
-				"original command line arguments",
-				nut_debug_level_args);
+			/* DEBUG_MIN is absent or commented-away in ups.conf
+			 * Negative value may be set by help() to be really quiet
+			 */
+			if (nut_debug_level_args > -1)
+				upslogx(LOG_INFO,
+					"Applying debug level %d from "
+					"original command line arguments",
+					nut_debug_level_args);
 			nut_debug_level = nut_debug_level_args;
 		}
 
@@ -1953,6 +2106,16 @@ static void loadconfig(void)
 	}
 
 	pconf_finish(&ctx);
+
+	/* TOTHINK: Should this warning be limited to non-WIN32 builds? */
+	if (!powerdownflag) {
+		upslogx(LOG_WARNING, "No POWERDOWNFLAG value was configured in %s!",
+			configfile);
+		upslogx(LOG_INFO,
+			"POWERDOWNFLAG should be a path to file that is normally "
+			"writeable for root user, and remains at least readable "
+			"late in shutdown after all unmounting completes.");
+	}
 }
 
 #ifndef WIN32
@@ -2399,8 +2562,9 @@ static void clear_pdflag(void)
 	ret = pdflag_status();
 
 	if (ret == -1)  {
-		upslogx(LOG_ERR, "POWERDOWNFLAG (%s) does not contain"
-			"the upsmon magic string - disabling!", powerdownflag);
+		upslogx(LOG_ERR, "POWERDOWNFLAG (%s) does not contain "
+			"the upsmon magic string (not a NUT file) - "
+			"disabling!", powerdownflag);
 		powerdownflag = NULL;
 		return;
 	}
@@ -2445,9 +2609,34 @@ static void help(const char *arg_progname)
 
 static void help(const char *arg_progname)
 {
-	printf("Monitors UPS servers and may initiate shutdown if necessary.\n\n");
+	int old_debug_level = nut_debug_level;
+	int old_debug_level_args = nut_debug_level_args;
+	int old_debug_level_global = nut_debug_level_global;
+
+	/* Try to get POWERDOWNFLAG? */
+	if (!powerdownflag) {
+		/* Avoid fatalx() on bad/absent configs */
+		reload_flag = -1;
+
+		/* Hush messages normally emitted by loadconfig() */
+		nut_debug_level = -2;
+		nut_debug_level_args = -2;
+		nut_debug_level_global = -2;
 
-	printf("usage: %s [OPTIONS]\n\n", arg_progname);
+		loadconfig();
+
+		nut_debug_level = old_debug_level;
+		nut_debug_level_args = old_debug_level_args;
+		nut_debug_level_global = old_debug_level_global;
+
+		/* Separate from logs emitted by loadconfig() */
+		/* printf("\n"); */
+	}
+
+	print_banner_once(arg_progname, 2);
+	printf("NUT client which monitors UPS servers and may initiate shutdown if necessary.\n");
+
+	printf("\nusage: %s [OPTIONS]\n\n", arg_progname);
 	printf("  -c <cmd>	send command to running process\n");
 	printf("		commands:\n");
 	printf("		 - fsd: shutdown all primary-mode UPSes (use with caution)\n");
@@ -2461,7 +2650,8 @@ static void help(const char *arg_progname)
 	printf("  -B		stay backgrounded even if debugging is bumped\n");
 	printf("  -V		display the version of this software\n");
 	printf("  -h		display this help\n");
-	printf("  -K		checks POWERDOWNFLAG, sets exit code to 0 if set\n");
+	printf("  -K		checks POWERDOWNFLAG (%s), sets exit code to 0 if set\n",
+		powerdownflag ? powerdownflag : "***NOT CONFIGURED***");
 	printf("  -p		always run privileged (disable privileged parent)\n");
 	printf("  -u <user>	run child as user <user> (ignored when using -p)\n");
 	printf("  -4		IPv4 only\n");
@@ -2693,6 +2883,40 @@ static void check_parent(void)
 	upslogx(LOG_ALERT, "Parent died - shutdown impossible");
 }
 
+static void init_Inhibitor(const char *prog)
+{
+	static int	sleep_inhibitor_fail_reported = 0;
+	static int	sleep_status_ability_reported = 0;
+
+	if (INVALID_FD(sleep_inhibitor_fd)) {
+		/* See https://www.freedesktop.org/software/systemd/man/latest/org.freedesktop.login1.html
+		 * and https://systemd.io/INHIBITOR_LOCKS/ documentation about option values.
+		 */
+		sleep_inhibitor_fd = Inhibit("sleep", prog, "Careful handling of OS sleep with regard to power device monitoring", "delay");
+		if (VALID_FD(sleep_inhibitor_fd)) {
+			upslogx(LOG_INFO, "%s: initialized OS integration for sleep inhibitor", prog);
+			sleep_inhibitor_fail_reported = 0;
+		} else {
+			if (!sleep_inhibitor_fail_reported) {
+				upslogx(LOG_WARNING, "%s: failed to initialize OS integration for sleep inhibitor", prog);
+			}
+			sleep_inhibitor_fail_reported = 1;
+		}
+
+		if (!sleep_status_ability_reported && isPreparingForSleepSupported()) {
+			/* At this point isSupported may be -1 (unknown yet),
+			 * make a query to be sure */
+			sleep_inhibitor_status = isPreparingForSleep();
+			if (isPreparingForSleepSupported()) {
+				upslogx(LOG_INFO, "%s: initialized OS integration for sleep/wake monitoring", prog);
+			} else {
+				upslogx(LOG_INFO, "%s: failed to initialize OS integration for sleep/wake monitoring", prog);
+			}
+			sleep_status_ability_reported = 1;
+		}
+	}
+}
+
 int main(int argc, char *argv[])
 {
 	const char	*prog = xbasename(argv[0]);
@@ -2725,7 +2949,7 @@ int main(int argc, char *argv[])
 	}
 #endif
 
-	printf("Network UPS Tools %s %s\n", prog, UPS_VERSION);
+	print_banner_once(prog, 0);
 
 	/* if no configuration file is specified on the command line, use default */
 	configfile = xmalloc(SMALLBUF);
@@ -2787,7 +3011,9 @@ int main(int argc, char *argv[])
 				run_as_user = xstrdup(optarg);
 				break;
 			case 'V':
-				/* just show the optional CONFIG_FLAGS banner */
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(prog, 1);
 				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
 			case '4':
@@ -2831,20 +3057,22 @@ int main(int argc, char *argv[])
 	 * for probing whether a competing older instance of this program
 	 * is running (error if it is).
 	 */
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
 #ifndef WIN32
 	/* If cmd == 0 we are starting and check if a previous instance
 	 * is running by sending signal '0' (i.e. 'kill <pid> 0' equivalent)
 	 */
 	if (oldpid < 0) {
-		cmdret = sendsignal(prog, cmd);
+		cmdret = sendsignal(prog, cmd, 1);
 	} else {
-		cmdret = sendsignalpid(oldpid, cmd);
+		cmdret = sendsignalpid(oldpid, cmd, prog, 1);
 	}
 
 #else	/* WIN32 */
 	if (cmd) {
 		/* Command the running daemon, it should be there */
-		cmdret = sendsignal(UPSMON_PIPE_NAME, cmd);
+		cmdret = sendsignal(UPSMON_PIPE_NAME, cmd, 1);
 	} else {
 		/* Starting new daemon, check for competition */
 		mutex = CreateMutex(NULL, TRUE, UPSMON_PIPE_NAME);
@@ -2890,8 +3118,9 @@ int main(int argc, char *argv[])
 		 */
 		upslogx(LOG_WARNING, "Could not %s PID file "
 			"to see if previous upsmon instance is "
-			"already running!",
-			(cmdret == -3 ? "find" : "parse"));
+			"already running or not!%s",
+			(cmdret == -3 ? "find" : "parse"),
+			(checking_flag ? " This is okay during OS shutdown, which is when checking POWERDOWNFLAG makes most sense." : ""));
 		break;
 
 	case -1:
@@ -2933,22 +3162,32 @@ int main(int argc, char *argv[])
 					(oldpid < 0 ? " or add '-P $PID' argument" : ""));
 				break;
 			}
-# else
+# else	/* not HAVE_SYSTEMD */
 			if (oldpid < 0) {
 				upslogx(LOG_NOTICE, "Try to add '-P $PID' argument");
 			}
-# endif
+# endif	/* not HAVE_SYSTEMD */
 #endif	/* not WIN32 */
 		}
 
 		exit((cmdret == 0) ? EXIT_SUCCESS : EXIT_FAILURE);
 	}
 
+	/* Restore the signal errors verbosity */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
+
 	argc -= optind;
 	argv += optind;
 
 	open_syslog(prog);
 
+	if (checking_flag) {
+		/* Do not normally report the UPSes we would monitor, etc.
+		 * from loadconfig() for just checking the killpower flag */
+		if (nut_debug_level == 0)
+			nut_debug_level = -2;
+	}
+
 	loadconfig();
 
 	/* CLI debug level can not be smaller than debug_min specified
@@ -3021,6 +3260,14 @@ int main(int argc, char *argv[])
 
 	while (exit_flag == 0) {
 		utype_t	*ups;
+		time_t	start, end, now;
+#ifndef WIN32
+		time_t	prev;
+#endif
+		double	dt = 0;
+
+		if (isInhibitSupported())
+			init_Inhibitor(prog);
 
 		upsnotify(NOTIFY_STATE_WATCHDOG, NULL);
 
@@ -3034,8 +3281,108 @@ int main(int argc, char *argv[])
 			upsnotify(NOTIFY_STATE_READY, NULL);
 		}
 
-		for (ups = firstups; ups != NULL; ups = ups->next)
+		if (isPreparingForSleepSupported()) {
+			if (sleep_inhibitor_status < 0) {
+				/* We may be coming fresh from an aborted loop cycle
+				 * with *its* finding of pending or finished OS sleep;
+				 * do not lose that knowledge by just reading "same as
+				 * before" (-1) with another query here! */
+				sleep_inhibitor_status = isPreparingForSleep();
+			} else if (!isInhibitSupported()) {
+				/* We can monitor OS sleep/wake changes, but could not
+				 * get an inhibition lock to sync this behavior nicely
+				 * (e.g. due to lacking permissions to get such lock).
+				 * Our information may be obsolete (e.g. we saw the
+				 * beginning of OS sleep, but by the time we got
+				 * to this line - we have already woken up) */
+				int	new_sleep_inhibitor_status = isPreparingForSleep();
+				if (new_sleep_inhibitor_status >= 0 && sleep_inhibitor_status != new_sleep_inhibitor_status) {
+					upsdebugx(2, "We had previously learned sleep_inhibitor_status=%d "
+						"in a hastily aborted older loop cycle, but by the time "
+						"we got to handle it - the current value is %d",
+						sleep_inhibitor_status, new_sleep_inhibitor_status);
+					sleep_inhibitor_status = new_sleep_inhibitor_status;
+				}
+			}
+			upsdebugx(5, "sleep_inhibitor_status=%d", sleep_inhibitor_status);
+		}
+		if (sleep_inhibitor_status == 1) {
+			/* Preparing for sleep */
+			do_notify(NULL, NOTIFY_SUSPEND_STARTING);
+			upslogx(LOG_INFO, "%s: Processing OS going to sleep", prog);
+			Uninhibit(&sleep_inhibitor_fd);
+
+			upsnotify(NOTIFY_STATE_RELOADING, NULL);
+			upsdebugx(0, "%s: Dozing off until system tells us otherwise; send a SIGHUP or SIGTERM to break the loop manually", prog);
+			while ((sleep_inhibitor_status = isPreparingForSleep()) == -1 && !reload_flag && !exit_flag) {
+				usleep(1000000);
+			}
+			if (nut_debug_level == 0) {
+				upsdebugx(0, "%s: Dozing off finished", prog);
+			} else {
+				upsdebugx(0, "%s: Dozing off finished: sleep_inhibitor_status=%d reload_flag=%d exit_flag=%d",
+					prog, sleep_inhibitor_status, reload_flag, exit_flag);
+			}
+
+			/*... when sleep_inhibitor_status has changed (to 0 after waking up?),
+			 * go to switch/case below. Or after a user signal, skip on... */
+			upsnotify(NOTIFY_STATE_READY, NULL);
+			upsnotify(NOTIFY_STATE_WATCHDOG, NULL);
+
+			if (exit_flag)
+				break;
+
+			if (reload_flag && sleep_inhibitor_status != 0) {
+				upslogx(LOG_WARNING, "%s: OS was last known to be preparing for sleep, and we were "
+					"interrupted by a reload signal. If the sleep does happen later, the system might "
+					"shut down after wake-up if UPS info is stale after a known critical power state!",
+					prog);
+				upsnotify(NOTIFY_STATE_RELOADING, NULL);
+				reload_conf();
+				upsnotify(NOTIFY_STATE_READY, NULL);
+			}
+			upsdebugx(5, "sleep_inhibitor_status=%d (after dozing off)", sleep_inhibitor_status);
+		}	/*... else go to switch/case below */
+
+		switch (sleep_inhibitor_status) {
+			case 0:	/* Waking up */
+				do_notify(NULL, NOTIFY_SUSPEND_FINISHED);
+				upslogx(LOG_INFO, "%s: Processing OS wake-up after sleep", prog);
+				upsnotify(NOTIFY_STATE_WATCHDOG, NULL);
+
+				upsnotify(NOTIFY_STATE_RELOADING, NULL);
+				init_Inhibitor(prog);
+
+				time(&now);
+				for (ups = firstups; ups != NULL; ups = ups->next) {
+					ups->status = 0;
+					ups->lastpoll = now;
+				}
+
+				set_reload_flag(1);
+				reload_conf();
+
+				upsnotify(NOTIFY_STATE_READY, NULL);
+				upsnotify(NOTIFY_STATE_WATCHDOG, NULL);
+
+				break;
+
+			case  1:	/* Handled above */
+			case -1:	/* Same as before */
+			case -2:	/* !isPreparingForSleepSupported() */
+			default:	/* Odd... */
+				break;
+		}
+		/* Reset the value, regardless of support */
+		sleep_inhibitor_status = -2;
+
+		for (ups = firstups; ups != NULL; ups = ups->next) {
+			if (isPreparingForSleepSupported() && (sleep_inhibitor_status = isPreparingForSleep()) >= 0) {
+				upsdebugx(2, "Aborting UPS polling sub-loop because OS is preparing for sleep or just woke up");
+				goto end_loop_cycle;
+			}
 			pollups(ups);
+		}
 
 		recalc();
 
@@ -3047,12 +3394,47 @@ int main(int argc, char *argv[])
 		/* reap children that have exited */
 		waitpid(-1, NULL, WNOHANG);
 
-		sleep(sleepval);
+		time(&start);
+		if (isPreparingForSleepSupported()) {
+			sleep_inhibitor_status = -2;
+			now = start;
+
+			while (sleep_inhibitor_status < 0 && dt < sleepval) {
+				prev = now;
+				sleep(1);
+				sleep_inhibitor_status = isPreparingForSleep();
+				time(&now);
+				dt = difftime(now, start);
+				upsdebugx(7, "start=%" PRIiMAX " now=%" PRIiMAX " dt=%g sleepval=%u sleep_inhibitor_status=%d",
+					(intmax_t)start, (intmax_t)now, dt, sleepval, sleep_inhibitor_status);
+				if (dt > (sleepval + 5) || difftime(now, prev) > 5) {
+					upsdebugx(2, "It seems we have slept without warning or the system clock was changed");
+					if (sleep_inhibitor_status < 0)
+						sleep_inhibitor_status = 0;	/* behave as woken up */
+				} else if (dt < 0) {
+					upsdebugx(2, "It seems the system clock was changed into the past");
+					sleep_inhibitor_status = 0;	/* behave as woken up */
+				}
+			}
+
+			if (sleep_inhibitor_status >= 0) {
+				upsdebugx(2, "Aborting polling delay between main loop cycles because OS is preparing for sleep or just woke up");
+				goto end_loop_cycle;
+			}
+		} else {
+			/* sleep tight */
+			sleep(sleepval);
+		}
+		time(&end);
 #else
 		maxhandle = 0;
-		memset(&handles,0,sizeof(handles));
+		memset(&handles, 0, sizeof(handles));
 
 		/* Wait on the read IO of each connections */
+		/* TODO: Windows suspend/hibernate tracking might fit here
+		 *  if we add a file handle to watch for... something, and
+		 *  so wake up quickly to skip the up-to-sleepval delay.
+		 */
 		for (conn = pipe_connhead; conn; conn = conn->next) {
 			handles[maxhandle] = conn->overlapped.hEvent;
 			maxhandle++;
@@ -3061,7 +3443,9 @@ int main(int argc, char *argv[])
 		handles[maxhandle] = pipe_connection_overlapped.hEvent;
 		maxhandle++;
 
-		ret = WaitForMultipleObjects(maxhandle,handles,FALSE,sleepval*1000);
+		time(&start);
+		ret = WaitForMultipleObjects(maxhandle, handles, FALSE, sleepval*1000);
+		time(&end);
 
 		if (ret == WAIT_FAILED) {
 			upslogx(LOG_ERR, "Wait failed");
@@ -3073,8 +3457,8 @@ int main(int argc, char *argv[])
 		}
 
 		/* Retrieve the signaled connection */
-		for(conn = pipe_connhead; conn != NULL; conn = conn->next) {
-			if( conn->overlapped.hEvent == handles[ret-WAIT_OBJECT_0]) {
+		for (conn = pipe_connhead; conn != NULL; conn = conn->next) {
+			if (conn->overlapped.hEvent == handles[ret-WAIT_OBJECT_0]) {
 				break;
 			}
 		}
@@ -3084,8 +3468,8 @@ int main(int argc, char *argv[])
 		}
 		/* one of the read event handle has been signaled */
 		else {
-			if( conn != NULL) {
-				if ( pipe_ready(conn) ) {
+			if (conn != NULL) {
+				if (pipe_ready(conn)) {
 					if (!strncmp(conn->buf, SIGCMD_FSD, sizeof(SIGCMD_FSD))) {
 						user_fsd(1);
 					}
@@ -3099,7 +3483,7 @@ int main(int argc, char *argv[])
 					}
 
 					else {
-						upslogx(LOG_ERR,"Unknown signal");
+						upslogx(LOG_ERR, "Unknown signal");
 					}
 
 					pipe_disconnect(conn);
@@ -3107,11 +3491,29 @@ int main(int argc, char *argv[])
 			}
 		}
 #endif
+
+		/* General-purpose handling of time jumps for OSes/run-times
+		 * without NUT direct support for suspend/inhibit */
+		dt = difftime(end, start);
+		if (dt > (sleepval + 5)) {
+			upsdebugx(2, "It seems we have slept without warning or the system clock was changed");
+			if (sleep_inhibitor_status < 0)
+				sleep_inhibitor_status = 0;	/* behave as woken up */
+		} else if (dt < 0) {
+			upsdebugx(2, "It seems the system clock was changed into the past");
+			if (sleep_inhibitor_status < 0)
+				sleep_inhibitor_status = 0;	/* behave as woken up */
+		}
+
+end_loop_cycle:
+		/* No-op to avoid a warning about label at end of compound statement */
+		(void)1;
 	}
 
 	upslogx(LOG_INFO, "Signal %d: exiting", exit_flag);
 	upsnotify(NOTIFY_STATE_STOPPING, "Signal %d: exiting", exit_flag);
 	upsmon_cleanup();
 
+	upsdebugx(1, "Finally exiting due to signal %d", exit_flag);
 	exit(EXIT_SUCCESS);
 }
diff --git a/clients/upsmon.h b/clients/upsmon.h
index 767e146709..383ae2becd 100644
--- a/clients/upsmon.h
+++ b/clients/upsmon.h
@@ -1,6 +1,9 @@
 /* upsmon.h - headers and other useful things for upsmon.h
 
-   Copyright (C) 2000  Russell Kroll <rkroll@exploits.org>
+   Copyright (C)
+     2000  Russell Kroll <rkroll@exploits.org>
+     2012  Arnaud Quette <arnaud.quette.free.fr>
+     2020-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -79,6 +82,7 @@ typedef struct {
 	time_t	lastncwarn;		/* time of last NOCOMM warning	*/
 
 	time_t	offsince;		/* time of recent entry into OFF state	*/
+	time_t	oblbsince;		/* time of recent entry into OB LB state (normally this causes immediate shutdown alert, unless we are configured to delay it)	*/
 
 	void	*next;
 }	utype_t;
@@ -88,20 +92,23 @@ typedef struct {
 #define NOTIFY_ONLINE	0	/* UPS went on-line                     */
 #define NOTIFY_ONBATT	1	/* UPS went on battery                  */
 #define NOTIFY_LOWBATT	2	/* UPS went to low battery              */
-#define NOTIFY_FSD		3	/* Primary upsmon set FSD flag          */
+#define NOTIFY_FSD	3	/* Primary upsmon set FSD flag          */
 #define NOTIFY_COMMOK	4	/* Communication established	            */
 #define NOTIFY_COMMBAD	5	/* Communication lost                   */
 #define NOTIFY_SHUTDOWN	6	/* System shutdown in progress          */
 #define NOTIFY_REPLBATT	7	/* UPS battery needs to be replaced     */
 #define NOTIFY_NOCOMM	8	/* UPS hasn't been contacted in a while	*/
 #define NOTIFY_NOPARENT	9	/* privileged parent process died       */
-#define NOTIFY_CAL		10	/* UPS is performing calibration        */
-#define NOTIFY_NOTCAL		11	/* UPS is performing calibration        */
+#define NOTIFY_CAL	10	/* UPS is performing calibration        */
+#define NOTIFY_NOTCAL	11	/* UPS is performing calibration        */
 #define NOTIFY_OFF	12	/* UPS is administratively OFF or asleep*/
 #define NOTIFY_NOTOFF	13	/* UPS is not anymore administratively OFF or asleep*/
 #define NOTIFY_BYPASS	14	/* UPS is administratively on bypass    */
 #define NOTIFY_NOTBYPASS	15	/* UPS is not anymore administratively on bypass    */
 
+#define NOTIFY_SUSPEND_STARTING	30	/* OS is entering sleep/suspend/hibernate slumber mode, and we know it   */
+#define NOTIFY_SUSPEND_FINISHED	31	/* OS just finished sleep/suspend/hibernate slumber mode, and we know it */
+
 /* notify flag values */
 
 #define NOTIFY_IGNORE  (1 << 0)        /* don't do anything                */
@@ -125,7 +132,7 @@ typedef struct {
 static struct {
 	int	type;
 	const	char	*name;
-	char	*msg;		/* NULL until overridden */
+	char	*msg;	/* NULL until overridden */
 	const char	*stockmsg;
 	int	flags;
 }	notifylist[] =
@@ -133,7 +140,7 @@ static struct {
 	{ NOTIFY_ONLINE,   "ONLINE",   NULL, "UPS %s on line power", NOTIFY_DEFAULT },
 	{ NOTIFY_ONBATT,   "ONBATT",   NULL, "UPS %s on battery", NOTIFY_DEFAULT },
 	{ NOTIFY_LOWBATT,  "LOWBATT",  NULL, "UPS %s battery is low", NOTIFY_DEFAULT },
-	{ NOTIFY_FSD,	   "FSD",      NULL, "UPS %s: forced shutdown in progress", NOTIFY_DEFAULT },
+	{ NOTIFY_FSD,      "FSD",      NULL, "UPS %s: forced shutdown in progress", NOTIFY_DEFAULT },
 	{ NOTIFY_COMMOK,   "COMMOK",   NULL, "Communications with UPS %s established", NOTIFY_DEFAULT },
 	{ NOTIFY_COMMBAD,  "COMMBAD",  NULL, "Communications with UPS %s lost", NOTIFY_DEFAULT },
 	{ NOTIFY_SHUTDOWN, "SHUTDOWN", NULL, "Auto logout and shutdown proceeding", NOTIFY_DEFAULT },
@@ -146,6 +153,10 @@ static struct {
 	{ NOTIFY_NOTOFF,   "NOTOFF",   NULL, "UPS %s: no longer administratively OFF or asleep", NOTIFY_DEFAULT },
 	{ NOTIFY_BYPASS,   "BYPASS",   NULL, "UPS %s: on bypass (powered, not protecting)", NOTIFY_DEFAULT },
 	{ NOTIFY_NOTBYPASS,"NOTBYPASS",NULL, "UPS %s: no longer on bypass", NOTIFY_DEFAULT },
+
+	{ NOTIFY_SUSPEND_STARTING, "SUSPEND_STARTING", NULL, "OS is entering sleep/suspend/hibernate mode", NOTIFY_DEFAULT },
+	{ NOTIFY_SUSPEND_FINISHED, "SUSPEND_FINISHED", NULL, "OS just finished sleep/suspend/hibernate mode, de-activating obsolete UPS readings to avoid an unfortunate shutdown", NOTIFY_DEFAULT },
+
 	{ 0, NULL, NULL, NULL, 0 }
 };
 
diff --git a/clients/upsrw.c b/clients/upsrw.c
index 2086d6de43..710d39d51e 100644
--- a/clients/upsrw.c
+++ b/clients/upsrw.c
@@ -47,10 +47,11 @@ struct list_t {
 
 static void usage(const char *prog)
 {
-	printf("Network UPS Tools %s %s\n\n", prog, UPS_VERSION);
-	printf("usage: %s [-h]\n", prog);
+	print_banner_once(prog, 2);
+	printf("NUT administration client program to set variables within UPS hardware.\n");
+
+	printf("\nusage: %s [-h]\n", prog);
 	printf("       %s [-s <variable>] [-u <username>] [-p <password>] [-w] [-t <timeout>] <ups>\n\n", prog);
-	printf("Demo program to set variables within UPS hardware.\n");
 	printf("\n");
 	printf("  -h            display this help text\n");
 	printf("  -V            display the version of this software\n");
@@ -668,7 +669,9 @@ int main(int argc, char **argv)
 			tracking_enabled = 1;
 			break;
 		case 'V':
-			printf("Network UPS Tools %s %s\n", prog, UPS_VERSION);
+			/* just show the version and optional
+			 * CONFIG_FLAGS banner if available */
+			print_banner_once(prog, 1);
 			nut_report_config_flags();
 			exit(EXIT_SUCCESS);
 		case 'h':
diff --git a/clients/upssched.c b/clients/upssched.c
index 9a8d00dd46..32e5b060be 100644
--- a/clients/upssched.c
+++ b/clients/upssched.c
@@ -43,17 +43,17 @@
 
 #include <sys/types.h>
 #ifndef WIN32
-#include <sys/wait.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-#include <netinet/in.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <poll.h>
+# include <sys/wait.h>
+# include <sys/socket.h>
+# include <sys/un.h>
+# include <netinet/in.h>
+# include <unistd.h>
+# include <fcntl.h>
+# include <poll.h>
 #else
-#include "wincompat.h"
-#include <winsock2.h>
-#include <ws2tcpip.h>
+# include "wincompat.h"
+# include <winsock2.h>
+# include <ws2tcpip.h>
 #endif
 
 #include "upssched.h"
@@ -75,7 +75,7 @@ static const	char	*upsname, *notify_type;
 
 #ifdef WIN32
 static OVERLAPPED connect_overlapped;
-#define BUF_LEN 512
+# define BUF_LEN 512
 #endif
 
 #define PARENT_STARTED		-2
@@ -286,6 +286,9 @@ static void us_serialize(int op)
 			ret = read(pipefd[0], &ch, 1);
 			close(pipefd[0]);
 			break;
+
+		default:
+			break;
 	}
 }
 #endif
@@ -361,7 +364,7 @@ static TYPE_FD open_sock(void)
 
 	/* Wait for a connection */
 	ConnectNamedPipe(fd,&connect_overlapped);
-#endif
+#endif /* WIN32 */
 
 	return fd;
 }
@@ -482,7 +485,7 @@ static int send_to_one(conn_t *conn, const char *fmt, ...)
 
 		return 0;	/* failed */
 	}
-#endif
+#endif /* WIN32 */
 
 	return 1;	/* OK */
 }
@@ -495,9 +498,9 @@ static TYPE_FD conn_add(TYPE_FD sockfd)
 	int	ret;
 	conn_t	*tmp, *last;
 	struct	sockaddr_un	saddr;
-#if defined(__hpux) && !defined(_XOPEN_SOURCE_EXTENDED)
+# if defined(__hpux) && !defined(_XOPEN_SOURCE_EXTENDED)
 	int			salen;
-#else
+# else
 	socklen_t	salen;
 #endif
 
@@ -625,7 +628,7 @@ static TYPE_FD conn_add(TYPE_FD sockfd)
 	upsdebugx(3, "new connection on handle %p", acc);
 
 	pconf_init(&conn->ctx, NULL);
-#endif
+#endif /* WIN32 */
 
 	return acc;
 }
@@ -753,7 +756,8 @@ static int sock_read(conn_t *conn)
 		/* Restart async read */
 		memset(conn->buf,0,sizeof(conn->buf));
 		ReadFile(conn->fd,conn->buf,1,NULL,&(conn->read_overlapped));
-#endif
+#endif /* WIN32 */
+
 		ret = pconf_char(&conn->ctx, ch);
 
 		if (ret == 0)	/* nothing to parse yet */
@@ -815,7 +819,7 @@ static void start_daemon(TYPE_FD lockfd)
 	/* child */
 
 	/* make fds 0-2 (typically) point somewhere defined */
-#ifdef HAVE_DUP2
+# ifdef HAVE_DUP2
 	/* system can close (if needed) and (re-)open a specific FD number */
 	if (1) { /* scoping */
 		TYPE_FD devnull = open("/dev/null", O_RDWR);
@@ -836,8 +840,8 @@ static void start_daemon(TYPE_FD lockfd)
 
 		close(devnull);
 	}
-#else
-# ifdef HAVE_DUP
+# else /* not HAVE_DUP2 */
+#  ifdef HAVE_DUP
 	/* opportunistically duplicate to the "lowest-available" FD number */
 	close(STDIN_FILENO);
 	if (open("/dev/null", O_RDWR) != STDIN_FILENO)
@@ -854,7 +858,7 @@ static void start_daemon(TYPE_FD lockfd)
 		if (dup(STDIN_FILENO) != STDERR_FILENO)
 			fatal_with_errno(EXIT_FAILURE, "dup /dev/null as STDERR");
 	}
-# else
+#  else /* not HAVE_DUP */
 	close(STDIN_FILENO);
 	if (open("/dev/null", O_RDWR) != STDIN_FILENO)
 		fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDIN");
@@ -870,8 +874,8 @@ static void start_daemon(TYPE_FD lockfd)
 		if (open("/dev/null", O_RDWR) != STDERR_FILENO)
 			fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDERR");
 	}
-# endif
-#endif
+#  endif /* not HAVE_DUP */
+# endif /* not HAVE_DUP2 */
 
 	pipefd = open_sock();
 
@@ -1048,7 +1052,7 @@ static void start_daemon(TYPE_FD lockfd)
 
 		checktimers();
 	}
-#endif
+#endif /* WIN32 */
 }
 
 /* --- 'client' functions --- */
@@ -1100,7 +1104,7 @@ static TYPE_FD try_connect(void)
 	if (VALID_FD(pipefd))
 		return pipefd;
 
-#endif
+#endif /* WIN32 */
 
 	return ERROR_FD;
 }
@@ -1289,7 +1293,7 @@ static void sendcmd(const char *cmd, const char *arg1, const char *arg2)
 			CloseHandle(pipefd);
 			continue;
 		}
-#endif
+#endif /* WIN32 */
 
 		if (!strncmp(buf, "OK", 2))
 			return;		/* success */
@@ -1530,6 +1534,11 @@ int main(int argc, char **argv)
 				/* just show the optional CONFIG_FLAGS banner */
 				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
+
+			default:
+				fatalx(EXIT_FAILURE,
+					"Error: unknown option -%c. Try -h for help.",
+					(char)i);
 		}
 	}
 
diff --git a/common/Makefile.am b/common/Makefile.am
index 569ad9c6ec..13bf15c15c 100644
--- a/common/Makefile.am
+++ b/common/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 AM_CFLAGS = -I$(top_builddir)/include -I$(top_srcdir)/include
 AM_CXXFLAGS = -I$(top_builddir)/include -I$(top_srcdir)/include
@@ -45,13 +45,27 @@ endif !BUILDING_IN_TREE
 $(top_builddir)/include/nut_version.h:
 	+@cd $(@D) && $(MAKE) $(AM_MAKEFLAGS) $(@F)
 
+# FIXME: If we maintain some of those helper libs as subsets of the others
+# (strictly), maybe build the lowest common denominator only and link the
+# bigger scopes with it (rinse and repeat)?
 libcommon_la_SOURCES = state.c str.c upsconf.c
 libcommonclient_la_SOURCES = state.c str.c
+
+# several other Makefiles include the two helpers common.c str.c (and
+# perhaps some other string-related code), so make them a library too;
+# note that LTLIBOBJS pulls in snprintf.c contents too.
+noinst_LTLIBRARIES += libcommonstr.la
+libcommonstr_la_SOURCES = str.c
+libcommonstr_la_CFLAGS = $(AM_CFLAGS) -DWITHOUT_LIBSYSTEMD=1
+libcommonstr_la_LIBADD = @LTLIBOBJS@ @BSDKVMPROCLIBS@
+
 if BUILDING_IN_TREE
   libcommon_la_SOURCES += common.c
+  libcommonstr_la_SOURCES += common.c
   libcommonclient_la_SOURCES += common.c
 else !BUILDING_IN_TREE
   nodist_libcommon_la_SOURCES = common.c
+  nodist_libcommonstr_la_SOURCES = common.c
   nodist_libcommonclient_la_SOURCES = common.c
   CLEANFILES += $(top_builddir)/common/common.c
   BUILT_SOURCES = common.c
@@ -62,6 +76,7 @@ if HAVE_STRPTIME
 else !HAVE_STRPTIME
   # fall back to NetBSD implem
   libcommon_la_SOURCES += strptime.c
+  libcommonstr_la_SOURCES += strptime.c
   libcommonclient_la_SOURCES += strptime.c
 endif !HAVE_STRPTIME
 
@@ -70,6 +85,7 @@ if HAVE_STRNLEN
 else !HAVE_STRNLEN
   # fall back to FreeBSD implem
   libcommon_la_SOURCES += strnlen.c
+  libcommonstr_la_SOURCES += strnlen.c
   libcommonclient_la_SOURCES += strnlen.c
 endif !HAVE_STRNLEN
 
@@ -78,9 +94,19 @@ if HAVE_STRSEP
 else !HAVE_STRSEP
   # fall back to simple implem
   libcommon_la_SOURCES += strsep.c
+  libcommonstr_la_SOURCES += strsep.c
   libcommonclient_la_SOURCES += strsep.c
 endif !HAVE_STRSEP
 
+if WANT_TIMEGM_FALLBACK
+  # fall back to simple implem
+  libcommon_la_SOURCES += timegm_fallback.c
+  libcommonstr_la_SOURCES += timegm_fallback.c
+  libcommonclient_la_SOURCES += timegm_fallback.c
+else !WANT_TIMEGM_FALLBACK
+  EXTRA_DIST += timegm_fallback.c
+endif !WANT_TIMEGM_FALLBACK
+
 if HAVE_WINDOWS
   libnutwincompat_la_SOURCES = wincompat.c $(top_srcdir)/include/wincompat.h
   libnutwincompat_la_LDFLAGS =
@@ -97,8 +123,8 @@ endif HAVE_WINDOWS
 
 # ensure inclusion of local implementation of missing systems functions
 # using LTLIBOBJS. Refer to configure.in/.ac -> AC_REPLACE_FUNCS
-libcommon_la_LIBADD = libparseconf.la @LTLIBOBJS@ @NETLIBS@
-libcommonclient_la_LIBADD = libparseconf.la @LTLIBOBJS@ @NETLIBS@
+libcommon_la_LIBADD = libparseconf.la @LTLIBOBJS@ @NETLIBS@ @BSDKVMPROCLIBS@
+libcommonclient_la_LIBADD = libparseconf.la @LTLIBOBJS@ @NETLIBS@ @BSDKVMPROCLIBS@
 
 libcommon_la_CFLAGS = $(AM_CFLAGS)
 libcommonclient_la_CFLAGS = $(AM_CFLAGS)
@@ -112,6 +138,9 @@ if HAVE_LIBREGEX
   libcommon_la_CFLAGS += $(LIBREGEX_CFLAGS)
   libcommon_la_LIBADD += $(LIBREGEX_LIBS)
 
+  libcommonstr_la_CFLAGS += $(LIBREGEX_CFLAGS)
+  libcommonstr_la_LIBADD += $(LIBREGEX_LIBS)
+
   libcommonclient_la_CFLAGS += $(LIBREGEX_CFLAGS)
   libcommonclient_la_LIBADD += $(LIBREGEX_LIBS)
 endif HAVE_LIBREGEX
diff --git a/common/common.c b/common/common.c
index 8e20c9607c..b126f79fa4 100644
--- a/common/common.c
+++ b/common/common.c
@@ -1,7 +1,7 @@
 /* common.c - common useful functions
 
    Copyright (C) 2000  Russell Kroll <rkroll@exploits.org>
-   Copyright (C) 2021-2022  Jim Klimov <jimklimov+nut@gmail.com>
+   Copyright (C) 2021-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -23,13 +23,19 @@
 
 #include <ctype.h>
 #ifndef WIN32
-#include <syslog.h>
-#include <errno.h>
-#include <pwd.h>
-#include <grp.h>
-#include <sys/un.h>
+# include <syslog.h>
+# include <errno.h>
+# include <pwd.h>
+# include <grp.h>
+# include <sys/un.h>
 #else
-#include <wincompat.h>
+# include <wincompat.h>
+# include <processthreadsapi.h>
+# include <psapi.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>	/* readlink */
 #endif
 
 #include <dirent.h>
@@ -37,6 +43,385 @@
 # include <sys/stat.h>
 #endif
 
+#if (defined WITH_LIBSYSTEMD_INHIBITOR) && (defined WITH_LIBSYSTEMD && WITH_LIBSYSTEMD) && (defined WITH_LIBSYSTEMD_INHIBITOR && WITH_LIBSYSTEMD_INHIBITOR) && !(defined(WITHOUT_LIBSYSTEMD) && (WITHOUT_LIBSYSTEMD))
+#  ifdef HAVE_SYSTEMD_SD_BUS_H
+#   include <systemd/sd-bus.h>
+#  endif
+/* Code below is inspired by https://systemd.io/INHIBITOR_LOCKS/ docs, and
+ * https://github.com/systemd/systemd/issues/34004 discussion which pointed
+ * to https://github.com/systemd/systemd/blob/main/src/login/inhibit.c tool
+ * and https://github.com/systemd/systemd/blob/main/src/basic/errno-util.h etc.
+ * and https://www.freedesktop.org/software/systemd/man/latest/sd_bus_call_method.html
+ */
+static int RET_NERRNO(int ret) {
+	if (ret < 0) {
+		if (errno > 0)
+			return -EINVAL;
+		return -errno;
+	}
+
+	return ret;
+}
+
+/* FIXME: Pedantically speaking, the attribute is assumed supported by GCC
+ *  and CLANG; practically - not sure if we have platforms with sufficiently
+ *  new libsystemd (its headers and example code also use this) and older or
+ *  different compilers. This can be addressed a bit more clumsily directly,
+ *  but we only want to do so if needed in real life. */
+#define _cleanup_(f)	__attribute__((cleanup(f)))
+
+/* The "bus_login_mgr" definition per
+ * https://github.com/systemd/systemd/blob/4cf7a676af9a79ff418227d8ff488dfca6f243ab/src/shared/bus-locator.c#L24 */
+#define SDBUS_DEST	"org.freedesktop.login1"
+#define SDBUS_PATH	"/org/freedesktop/login1"
+#define SDBUS_IFACE	"org.freedesktop.login1.Manager"
+
+static /*_cleanup_(sd_bus_flush_close_unrefp)*/ sd_bus	*systemd_bus = NULL;
+static int	isSupported_Inhibit = -1, isSupported_Inhibit_errno = 0;
+static int	isSupported_PreparingForSleep = -1, isSupported_PreparingForSleep_errno = 0;
+
+static void close_sdbus_once(void) {
+	/* Per https://manpages.debian.org/testing/libsystemd-dev/sd_bus_flush_close_unrefp.3.en.html
+	 * these end-of-life methods do not tell us if we succeeded or failed
+	 * closing the bus connection in any manner, so we here also do not.
+	 */
+
+	if (!systemd_bus) {
+		errno = 0;
+		return;
+	}
+
+	upsdebugx(1, "%s: trying", __func__);
+	errno = 0;
+	sd_bus_flush_close_unrefp(&systemd_bus);
+	systemd_bus = NULL;
+}
+
+static int open_sdbus_once(const char *caller) {
+	static int	openedOnce = 0, faultReported = 0;
+	int	r = 1;
+
+	errno = 0;
+	if (systemd_bus)
+		return r;
+
+# if defined HAVE_SD_BUS_OPEN_SYSTEM_WITH_DESCRIPTION && HAVE_SD_BUS_OPEN_SYSTEM_WITH_DESCRIPTION
+	r = sd_bus_open_system_with_description(&systemd_bus, "Bus connection for Network UPS Tools sleep/suspend/hibernate handling");
+# else
+	r = sd_bus_open_system(&systemd_bus);
+# endif
+	if (r < 0 || !systemd_bus) {
+		if (r >= 0) {
+			if (!faultReported)
+				upsdebugx(1, "%s: Failed to acquire bus for %s(): "
+					"got null pointer and %d exit-code; setting EINVAL",
+					__func__, NUT_STRARG(caller), r);
+			r = -EINVAL;
+		} else {
+			if (!faultReported)
+				upsdebugx(1, "%s: Failed to acquire bus for %s() (%d): %s",
+					__func__, NUT_STRARG(caller), r, strerror(-r));
+		}
+		faultReported = 1;
+	} else {
+		upsdebugx(1, "%s: succeeded for %s", __func__, NUT_STRARG(caller));
+		faultReported = 0;
+	}
+
+	if (systemd_bus && !openedOnce) {
+		openedOnce = 1;
+		atexit(close_sdbus_once);
+	}
+
+	if (systemd_bus) {
+# if !(defined HAVE_SD_BUS_OPEN_SYSTEM_WITH_DESCRIPTION && HAVE_SD_BUS_OPEN_SYSTEM_WITH_DESCRIPTION)
+#  if defined HAVE_SD_BUS_SET_DESCRIPTION && HAVE_SD_BUS_SET_DESCRIPTION
+		if (sd_bus_set_description(systemd_bus, "Bus connection for Network UPS Tools sleep/suspend/hibernate handling") < 0)
+			upsdebugx(1, "%s: failed to sd_bus_set_description(), oh well", __func__);
+#  endif
+# endif
+
+		/* second arg for (bool)arg_ask_password - 0 for the non-interactive daemon */
+		sd_bus_set_allow_interactive_authorization(systemd_bus, 0);
+	}
+
+	return r;
+}
+
+static int would_reopen_sdbus(int r) {
+	if (r >= 0)
+		return 0;
+
+	switch (-r) {
+		/* Rule out issues that would not clear themselves (e.g. not stale connections) */
+		case ENOENT:
+		case EPERM:
+		case EACCES:
+			return 0;
+	}
+
+	return 1;
+}
+
+static int reopen_sdbus_once(int r, const char *caller, const char *purpose)
+{
+	if (r >= 0)
+		return r;
+
+	switch (-r) {
+		/* Rule out issues that would not clear themselves (e.g. not stale connections) */
+		case ENOENT:
+		case EPERM:
+		case EACCES:
+			break;
+
+		/* An "Invalid request descriptor" might fit this bill */
+		default:
+			upsdebugx(1, "%s for %s() for %s failed (%d) once, will retry D-Bus connection: %s",
+				__func__, caller, purpose, r, strerror(-r));
+
+			close_sdbus_once();
+			r = open_sdbus_once(caller);
+			if (r < 0) {
+				/* Errors, if any, reported above */
+				return r;
+			}
+			break;
+	}
+
+	return r;
+}
+
+int isInhibitSupported(void)
+{
+	return isSupported_Inhibit;
+}
+
+int isPreparingForSleepSupported(void)
+{
+	return isSupported_PreparingForSleep;
+}
+
+TYPE_FD Inhibit(const char *arg_what, const char *arg_who, const char *arg_why, const char *arg_mode)
+{
+	_cleanup_(sd_bus_error_free) sd_bus_error	error = SD_BUS_ERROR_NULL;
+	_cleanup_(sd_bus_message_unrefp) sd_bus_message	*reply = NULL;
+	int	r;
+	TYPE_FD	fd = ERROR_FD;
+
+	if (isSupported_Inhibit == 0) {
+		/* Already determined that we can not use it, e.g. due to perms */
+		errno = isSupported_Inhibit_errno;
+		return -errno;
+	}
+
+	/* Not found in public headers:
+	bool	arg_ask_password = true;
+	(void) polkit_agent_open_if_enabled(BUS_TRANSPORT_LOCAL, arg_ask_password);
+	 */
+
+	r = open_sdbus_once(__func__);
+	if (r < 0) {
+		/* Errors, if any, reported above */
+		return r;
+	}
+
+	r = sd_bus_call_method(systemd_bus, SDBUS_DEST, SDBUS_PATH, SDBUS_IFACE, "Inhibit", &error, &reply, "ssss", arg_what, arg_who, arg_why, arg_mode);
+	if (r < 0) {
+		if (would_reopen_sdbus(r)) {
+			if ((r = reopen_sdbus_once(r, __func__, "sd_bus_call_method()")) < 0)
+				return r;
+
+			r = sd_bus_call_method(systemd_bus, SDBUS_DEST, SDBUS_PATH, SDBUS_IFACE, "Inhibit", &error, &reply, "ssss", arg_what, arg_who, arg_why, arg_mode);
+		} else {
+			/* Permissions for the privileged operation... did it ever succeed? */
+			if (isSupported_Inhibit < 0) {
+				upsdebugx(1, "%s: %s() failed seemingly due to permissions, marking %s as not supported",
+					__func__, "sd_bus_call_method", "Inhibit");
+				isSupported_Inhibit = 0;
+				isSupported_Inhibit_errno = r;
+			}
+		}
+
+		if (r < 0) {
+			upsdebugx(1, "%s: %s() failed (%d): %s",
+				__func__, "sd_bus_call_method", r, strerror(-r));
+			if (error.message && *(error.message))
+				upsdebugx(2, "%s: details from libsystemd: %s",
+					__func__, error.message);
+			return r;
+		} else {
+			upsdebugx(1, "%s: reconnection to D-Bus helped with %s()",
+				__func__, "sd_bus_call_method");
+		}
+	}
+
+	r = sd_bus_message_read_basic(reply, SD_BUS_TYPE_UNIX_FD, &fd);
+	if (r < 0) {
+		upsdebugx(1, "%s: %s() failed (%d): %s",
+			__func__, "sd_bus_message_read_basic", r, strerror(-r));
+		if (isSupported_Inhibit < 0 && !would_reopen_sdbus(r)) {
+			upsdebugx(1, "%s: %s() failed seemingly due to permissions, marking %s as not supported",
+				__func__, "sd_bus_message_read_basic", "Inhibit");
+			isSupported_Inhibit = 0;
+			isSupported_Inhibit_errno = r;
+		}
+		return r;
+	}
+
+	/* Data query succeeded, so it is supported */
+	isSupported_Inhibit = 1;
+
+	/* NOTE: F_DUPFD_CLOEXEC is in POSIX.1-2008 (Linux 2.6.24); seek out
+	 * an alternative sequence of options if needed on older systems */
+	r = RET_NERRNO(fcntl(fd, F_DUPFD_CLOEXEC, 3));
+	if (r < 0) {
+		upsdebugx(1, "%s: fcntl() failed (%d): %s",
+			__func__, r, strerror(-r));
+		return fd;
+	}
+
+	return r;
+}
+
+void Uninhibit(TYPE_FD *fd_ptr)
+{
+	if (!fd_ptr)
+		return;
+	if (INVALID_FD(*fd_ptr))
+		return;
+
+	/* Closing the socket allows systemd to proceed (we un-inhibit our lock on system
+	 * life-cycle handling). After waking up, we should Inhibit() anew, if needed.
+	 */
+	close(*fd_ptr);
+	*fd_ptr = ERROR_FD;
+}
+
+int isPreparingForSleep(void)
+{
+	static int32_t	prev = -1;
+	int32_t	val = 0;	/* 4-byte int expected for SD_BUS_TYPE_BOOLEAN aka 'b' */
+	int	r;
+	_cleanup_(sd_bus_error_free) sd_bus_error	error = SD_BUS_ERROR_NULL;
+
+	if (isSupported_PreparingForSleep == 0) {
+		/* Already determined that we can not use it, e.g. due to perms */
+		errno = isSupported_PreparingForSleep_errno;
+		return -errno;
+	}
+
+	r = open_sdbus_once(__func__);
+	if (r < 0) {
+		/* Errors, if any, reported above */
+		return r;
+	}
+
+	/* @org.freedesktop.DBus.Property.EmitsChangedSignal("false")
+	 *     readonly b PreparingForSleep = ...;
+	 * https://www.freedesktop.org/software/systemd/man/latest/org.freedesktop.login1.html
+	 * https://www.freedesktop.org/software/systemd/man/latest/sd_bus_set_property.html
+	 * https://www.freedesktop.org/software/systemd/man/latest/sd_bus_message_append.html (data types)
+	 */
+	r = sd_bus_get_property_trivial(systemd_bus, SDBUS_DEST, SDBUS_PATH, SDBUS_IFACE, "PreparingForSleep", &error, SD_BUS_TYPE_BOOLEAN, &val);
+	if (r < 0) {
+		if (would_reopen_sdbus(r)) {
+			if ((r = reopen_sdbus_once(r, __func__, "sd_bus_get_property_trivial()")) < 0)
+				return r;
+
+			r = sd_bus_get_property_trivial(systemd_bus, SDBUS_DEST, SDBUS_PATH, SDBUS_IFACE, "PreparingForSleep", &error, 'b', &val);
+		} else {
+			if (isSupported_PreparingForSleep < 0) {
+				upsdebugx(1, "%s: %s() failed seemingly due to permissions, marking %s as not supported",
+					__func__, "sd_bus_get_property_trivial", "PreparingForSleep");
+				isSupported_PreparingForSleep = 0;
+				isSupported_PreparingForSleep_errno = r;
+			}
+		}
+
+		if (r < 0) {
+			upsdebugx(1, "%s: %s() failed (%d): %s",
+				__func__, "sd_bus_get_property_trivial", r, strerror(-r));
+			if (error.message && *(error.message))
+				upsdebugx(2, "%s: details from libsystemd: %s",
+					__func__, error.message);
+			return r;
+		} else {
+			upsdebugx(1, "%s: reconnection to D-Bus helped with %s()",
+				__func__, "sd_bus_get_property_trivial");
+		}
+	}
+
+	/* Data query succeeded, so it is supported */
+	isSupported_PreparingForSleep = 1;
+
+	if (val == prev) {
+		/* Unchanged */
+		return -1;
+	}
+
+	/* First run and not immediately going to sleep, assume unchanged (no-op for upsmon et al) */
+	if (prev < 0 && !val) {
+		prev = val;
+		return -1;
+	}
+
+	/* 0 or 1 */
+	prev = val;
+	return val;
+}
+
+#else	/* not WITH_LIBSYSTEMD_INHIBITOR */
+
+int isInhibitSupported(void)
+{
+	return 0;
+}
+
+int isPreparingForSleepSupported(void)
+{
+	return 0;
+}
+
+TYPE_FD Inhibit(const char *arg_what, const char *arg_who, const char *arg_why, const char *arg_mode)
+{
+	static int	reported = 0;
+	NUT_UNUSED_VARIABLE(arg_what);
+	NUT_UNUSED_VARIABLE(arg_who);
+	NUT_UNUSED_VARIABLE(arg_why);
+	NUT_UNUSED_VARIABLE(arg_mode);
+
+	if (!reported) {
+		upsdebugx(6, "%s: Not implemented on this platform", __func__);
+		reported = 1;
+	}
+	return ERROR_FD;
+}
+
+int isPreparingForSleep(void)
+{
+	static int	reported = 0;
+
+	if (!reported) {
+		upsdebugx(6, "%s: Not implemented on this platform", __func__);
+		reported = 1;
+	}
+	return -1;
+}
+
+void Uninhibit(TYPE_FD *fd_ptr)
+{
+	static int	reported = 0;
+	NUT_UNUSED_VARIABLE(fd_ptr);
+
+	if (!reported) {
+		upsdebugx(6, "%s: Not implemented on this platform", __func__);
+		reported = 1;
+	}
+}
+
+#endif	/* not WITH_LIBSYSTEMD_INHIBITOR */
+
 #ifdef WITH_LIBSYSTEMD
 # include <systemd/sd-daemon.h>
 /* upsnotify() debug-logs its reports; a watchdog ping is something we
@@ -48,15 +433,15 @@ static int upsnotify_reported_disabled_systemd = 0;
 /* Define this to 1 for lots of spam at debug level 6, and ignoring WATCHDOG_PID
  * so trying to post reports anyway if WATCHDOG_USEC is valid */
 #  define DEBUG_SYSTEMD_WATCHDOG 0
-# endif
-#endif
+# endif	/* DEBUG_SYSTEMD_WATCHDOG */
+#endif	/* WITH_LIBSYSTEMD */
 /* Similarly for only reporting once if the notification subsystem is not built-in */
 static int upsnotify_reported_disabled_notech = 0;
 static int upsnotify_report_verbosity = -1;
 
 /* the reason we define UPS_VERSION as a static string, rather than a
 	macro, is to make dependency tracking easier (only common.o depends
-	on nut_version_macro.h), and also to prevent all sources from
+	on nut_version.h), and also to prevent all sources from
 	having to be recompiled each time the version changes (they only
 	need to be re-linked). */
 #include "nut_version.h"
@@ -79,6 +464,17 @@ const char *UPS_VERSION = NUT_VERSION_MACRO;
 #include <sys/types.h>
 #include <limits.h>
 #include <stdlib.h>
+
+#if defined(HAVE_LIB_BSD_KVM_PROC) && HAVE_LIB_BSD_KVM_PROC
+# include <kvm.h>
+# include <sys/param.h>
+# include <sys/sysctl.h>
+#endif
+
+#if defined(HAVE_LIB_ILLUMOS_PROC) && HAVE_LIB_ILLUMOS_PROC
+# include <procfs.h>
+#endif
+
 pid_t get_max_pid_t(void)
 {
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
@@ -108,6 +504,23 @@ pid_t get_max_pid_t(void)
 #endif
 }
 
+	/* Normally sendsignalfn(), sendsignalpid() and related methods call
+	 * upslogx() to report issues such as failed fopen() of PID file,
+	 * failed parse of its contents, inability to send a signal (absent
+	 * process or some other issue like permissions).
+	 * Some of these low-level reports look noisy and scary to users,
+	 * others are a bit confusing ("PID file not found... is it bad or
+	 * good, what do I do with that knowledge?") so several consuming
+	 * programs actually parse the returned codes to formulate their
+	 * own messages like "No earlier instance of this daemon was found
+	 * running" and users benefit even less from low-level reports.
+	 * This variable and its values are a bit of internal detail between
+	 * certain NUT programs to hush the low-level reports when they are
+	 * not being otherwise debugged (e.g. nut_debug_level < 1).
+	 * Default value allows all those messages to appear.
+	 */
+	int	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
+
 	int	nut_debug_level = 0;
 	int	nut_log_level = 0;
 	static	int	upslog_flags = UPSLOG_STDERR;
@@ -129,11 +542,124 @@ static int xbit_test(int val, int flag)
 	return ((val & flag) == flag);
 }
 
+int syslog_is_disabled(void)
+{
+	static int value = -1;
+
+	if (value < 0) {
+		char *s = getenv("NUT_DEBUG_SYSLOG");
+		/* Not set or not disabled by the setting: default is enabled (inversed per method name) */
+		value = 0;
+		if (s) {
+			if (!strcmp(s, "stderr")) {
+				value = 1;
+			} else if (!strcmp(s, "none") || !strcmp(s, "false")) {
+				value = 2;
+			} else if (!strcmp(s, "syslog") || !strcmp(s, "true") || !strcmp(s, "default")) {
+				/* Just reserve a value to quietly do the default */
+				value = 0;
+			} else {
+				upsdebugx(0, "%s: unknown NUT_DEBUG_SYSLOG='%s' value, ignored (assuming enabled)",
+					__func__, s);
+			}
+		}
+	}
+
+	return value;
+}
+
+int banner_is_disabled(void)
+{
+	static int value = -1;
+
+	if (value < 0) {
+		char *s = getenv("NUT_QUIET_INIT_BANNER");
+		/* Envvar present and empty or true-ish means NUT tool name+version
+		 * banners disabled by the setting: default is enabled (inversed per
+		 * method name) */
+		value = 0;
+		if (s) {
+			if (*s == '\0' || !strcasecmp(s, "true") || strcmp(s, "1")) {
+				value = 1;
+			}
+		}
+	}
+
+	return value;
+}
+
+const char *describe_NUT_VERSION_once(void)
+{
+	static char	buf[LARGEBUF];
+	static const char	*printed = NULL;
+
+	if (printed)
+		return printed;
+
+	memset(buf, 0, sizeof(buf));
+
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+	/* NOTE: Some compilers deduce that macro-based decisions about
+	 * NUT_VERSION_IS_RELEASE make one of codepaths unreachable in
+	 * a particular build. So we pragmatically handwave this away.
+	 */
+	if (1 < snprintf(buf, sizeof(buf),
+		"%s %s%s%s",
+		NUT_VERSION_MACRO,
+		NUT_VERSION_IS_RELEASE ? "release" : "(development iteration after ",
+		NUT_VERSION_IS_RELEASE ? "" : NUT_VERSION_SEMVER_MACRO,
+		NUT_VERSION_IS_RELEASE ? "" : ")"
+	)) {
+		printed = buf;
+	} else {
+		upslogx(LOG_WARNING, "%s: failed to report detailed NUT version", __func__);
+		printed = UPS_VERSION;
+	}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
+
+	return printed;
+}
+
+int print_banner_once(const char *prog, int even_if_disabled)
+{
+	static int	printed = 0;
+	static int	ret = -1;
+
+	if (printed)
+		return ret;
+
+	if (!banner_is_disabled() || even_if_disabled) {
+		ret = printf("Network UPS Tools %s %s%s\n",
+			prog, describe_NUT_VERSION_once(),
+			even_if_disabled == 2 ? "\n" : "");
+		fflush(stdout);
+		if (ret > 0)
+			printed = 1;
+	}
+
+	return ret;
+}
+
 /* enable writing upslog_with_errno() and upslogx() type messages to
    the syslog */
 void syslogbit_set(void)
 {
-	xbit_set(&upslog_flags, UPSLOG_SYSLOG);
+	if (!syslog_is_disabled())
+		xbit_set(&upslog_flags, UPSLOG_SYSLOG);
 }
 
 /* get the syslog ready for us */
@@ -142,12 +668,15 @@ void open_syslog(const char *progname)
 #ifndef WIN32
 	int	opt;
 
+	if (syslog_is_disabled())
+		return;
+
 	opt = LOG_PID;
 
 	/* we need this to grab /dev/log before chroot */
-#ifdef LOG_NDELAY
+# ifdef LOG_NDELAY
 	opt |= LOG_NDELAY;
-#endif
+# endif	/* LOG_NDELAY */
 
 	openlog(progname, opt, LOG_FACILITY);
 
@@ -180,31 +709,43 @@ void open_syslog(const char *progname)
 		break;
 	default:
 		fatalx(EXIT_FAILURE, "Invalid log level threshold");
-#else
+# else
 	case 0:
 		break;
 	default:
 		upslogx(LOG_INFO, "Changing log level threshold not possible");
 		break;
-#endif
+# endif	/* HAVE_SETLOGMASK && HAVE_DECL_LOG_UPTO */
 	}
 #else
 	EventLogName = progname;
-#endif
+#endif	/* WIND32 */
 }
 
 /* close ttys and become a daemon */
 void background(void)
 {
+	/* Normally we enable SYSLOG and disable STDERR,
+	 * unless NUT_DEBUG_SYSLOG envvar interferes as
+	 * interpreted in syslog_is_disabled() method: */
+	int	syslog_disabled = syslog_is_disabled(),
+		stderr_disabled = (syslog_disabled == 0 || syslog_disabled == 2);
+
 #ifndef WIN32
 	int	pid;
 
 	if ((pid = fork()) < 0)
 		fatal_with_errno(EXIT_FAILURE, "Unable to enter background");
+#endif
 
-	xbit_set(&upslog_flags, UPSLOG_SYSLOG);
-	xbit_clear(&upslog_flags, UPSLOG_STDERR);
+	if (!syslog_disabled)
+		/* not disabled: NUT_DEBUG_SYSLOG is unset or invalid */
+		xbit_set(&upslog_flags, UPSLOG_SYSLOG);
+	if (stderr_disabled)
+		/* NUT_DEBUG_SYSLOG="none" or unset/invalid */
+		xbit_clear(&upslog_flags, UPSLOG_STDERR);
 
+#ifndef WIN32
 	if (pid != 0) {
 		/* parent */
 		/* these are typically fds 0-2: */
@@ -217,7 +758,7 @@ void background(void)
 	/* child */
 
 	/* make fds 0-2 (typically) point somewhere defined */
-#ifdef HAVE_DUP2
+# ifdef HAVE_DUP2
 	/* system can close (if needed) and (re-)open a specific FD number */
 	if (1) { /* scoping */
 		TYPE_FD devnull = open("/dev/null", O_RDWR);
@@ -228,13 +769,15 @@ void background(void)
 			fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDIN");
 		if (dup2(devnull, STDOUT_FILENO) != STDOUT_FILENO)
 			fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDOUT");
-		if (dup2(devnull, STDERR_FILENO) != STDERR_FILENO)
-			fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDERR");
+		if (stderr_disabled) {
+			if (dup2(devnull, STDERR_FILENO) != STDERR_FILENO)
+				fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDERR");
+		}
 
 		close(devnull);
 	}
-#else
-# ifdef HAVE_DUP
+# else
+#  ifdef HAVE_DUP
 	/* opportunistically duplicate to the "lowest-available" FD number */
 	close(STDIN_FILENO);
 	if (open("/dev/null", O_RDWR) != STDIN_FILENO)
@@ -244,10 +787,12 @@ void background(void)
 	if (dup(STDIN_FILENO) != STDOUT_FILENO)
 		fatal_with_errno(EXIT_FAILURE, "dup /dev/null as STDOUT");
 
-	close(STDERR_FILENO);
-	if (dup(STDIN_FILENO) != STDERR_FILENO)
-		fatal_with_errno(EXIT_FAILURE, "dup /dev/null as STDERR");
-# else
+	if (stderr_disabled) {
+		close(STDERR_FILENO);
+		if (dup(STDIN_FILENO) != STDERR_FILENO)
+			fatal_with_errno(EXIT_FAILURE, "dup /dev/null as STDERR");
+	}
+#  else
 	close(STDIN_FILENO);
 	if (open("/dev/null", O_RDWR) != STDIN_FILENO)
 		fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDIN");
@@ -256,20 +801,18 @@ void background(void)
 	if (open("/dev/null", O_RDWR) != STDOUT_FILENO)
 		fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDOUT");
 
-	close(STDERR_FILENO);
-	if (open("/dev/null", O_RDWR) != STDERR_FILENO)
-		fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDERR");
+	if (stderr_disabled) {
+		close(STDERR_FILENO);
+		if (open("/dev/null", O_RDWR) != STDERR_FILENO)
+			fatal_with_errno(EXIT_FAILURE, "re-open /dev/null as STDERR");
+	}
+#  endif
 # endif
-#endif
 
-#ifdef HAVE_SETSID
+# ifdef HAVE_SETSID
 	setsid();		/* make a new session to dodge signals */
-#endif
-
-#else /* WIN32 */
-	xbit_set(&upslog_flags, UPSLOG_SYSLOG);
-	xbit_clear(&upslog_flags, UPSLOG_STDERR);
-#endif
+# endif
+#endif	/* not WIN32 */
 
 	upslogx(LOG_INFO, "Startup successful");
 }
@@ -321,77 +864,749 @@ struct passwd *get_user_pwent(const char *name)
 #endif
 }
 
-/* change to the user defined in the struct */
-void become_user(struct passwd *pw)
+/* change to the user defined in the struct */
+void become_user(struct passwd *pw)
+{
+#ifndef WIN32
+	/* if we can't switch users, then don't even try */
+	intmax_t initial_uid = getuid();
+	intmax_t initial_euid = geteuid();
+
+	if (!pw) {
+		upsdebugx(1, "Can not become_user(<null>), skipped");
+		return;
+	}
+
+	if ((initial_euid != 0) && (initial_uid != 0)) {
+		intmax_t initial_gid = getgid();
+		if (initial_euid == (intmax_t)pw->pw_uid
+		||   initial_uid == (intmax_t)pw->pw_uid
+		) {
+			upsdebugx(1, "No need to become_user(%s): "
+				"already UID=%jd GID=%jd",
+				pw->pw_name, initial_uid, initial_gid);
+		} else {
+			upsdebugx(1, "Can not become_user(%s): "
+				"not root initially, "
+				"remaining UID=%jd GID=%jd",
+				pw->pw_name, initial_uid, initial_gid);
+		}
+		return;
+	}
+
+	if (initial_uid == 0)
+		if (seteuid(0))
+			fatal_with_errno(EXIT_FAILURE, "getuid gave 0, but seteuid(0) failed");
+
+	if (initgroups(pw->pw_name, pw->pw_gid) == -1)
+		fatal_with_errno(EXIT_FAILURE, "initgroups");
+
+	if (setgid(pw->pw_gid) == -1)
+		fatal_with_errno(EXIT_FAILURE, "setgid");
+
+	if (setuid(pw->pw_uid) == -1)
+		fatal_with_errno(EXIT_FAILURE, "setuid");
+
+	upsdebugx(1, "Succeeded to become_user(%s): now UID=%jd GID=%jd",
+		pw->pw_name, (intmax_t)getuid(), (intmax_t)getgid());
+#else
+	upsdebugx(1, "Can not become_user(%s): not implemented on this platform",
+		pw ? pw->pw_name : "<null>");
+#endif
+}
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_BESIDEFUNC) && (!defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_INSIDEFUNC) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS_BESIDEFUNC) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE_BESIDEFUNC) )
+# pragma GCC diagnostic push
+#endif
+#if (!defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_INSIDEFUNC) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS_BESIDEFUNC)
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+#if (!defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_INSIDEFUNC) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE_BESIDEFUNC)
+# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+/* drop down into a directory and throw away pointers to the old path */
+void chroot_start(const char *path)
+{
+	if (chdir(path))
+		fatal_with_errno(EXIT_FAILURE, "chdir(%s)", path);
+
+#ifndef WIN32
+	if (chroot(path))
+		fatal_with_errno(EXIT_FAILURE, "chroot(%s)", path);
+
+#else
+	upsdebugx(1, "Can not chroot into %s: not implemented on this platform", path);
+#endif
+
+	if (chdir("/"))
+		fatal_with_errno(EXIT_FAILURE, "chdir(/)");
+
+#ifndef WIN32
+	upsdebugx(1, "chrooted into %s", path);
+#endif
+}
+
+char * getprocname(pid_t pid)
+{
+	/* Try to identify process (program) name for the given PID,
+	 * return NULL if we can not for any reason (does not run,
+	 * no rights, do not know how to get it on current OS, etc.)
+	 * If the returned value is not NULL, caller should free() it.
+	 * Some implementation pieces borrowed from
+	 * https://man7.org/linux/man-pages/man2/readlink.2.html and
+	 * https://github.com/openbsd/src/blob/master/bin/ps/ps.c
+	 * NOTE: Very much platform-dependent!
+	 */
+	char	*procname = NULL;
+	size_t	procnamelen = 0;
+#ifdef UNIX_PATH_MAX
+	char	pathname[UNIX_PATH_MAX];
+#else
+	char	pathname[PATH_MAX];
+#endif
+	struct stat	st;
+
+#ifdef WIN32
+	/* Try Windows API calls, then fall through to /proc emulation in MinGW/MSYS2
+	 * https://stackoverflow.com/questions/1591342/c-how-to-determine-if-a-windows-process-is-running
+	 * http://cppip.blogspot.com/2013/01/check-if-process-is-running.html
+	 */
+	upsdebugx(5, "%s: begin to query WIN32 process info", __func__);
+	HANDLE process = OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, FALSE, (DWORD)pid);
+	if (process) {
+		DWORD	ret = GetModuleFileNameExA(
+				process,	/* hProcess */
+				NULL,		/* hModule */
+				(LPSTR)pathname,
+				(DWORD)(sizeof(pathname))
+			);
+		CloseHandle(process);
+		pathname[sizeof(pathname) - 1] = '\0';
+
+		if (ret) {
+			/* length of the string copied to the buffer */
+			procnamelen = strlen(pathname);
+
+			upsdebugx(3, "%s: try to parse the name from WIN32 process info",
+				__func__);
+			if (ret != procnamelen) {
+				upsdebugx(3, "%s: length mismatch getting WIN32 process info: %"
+					PRIuMAX " vs. " PRIuSIZE,
+					__func__, (uintmax_t)ret, procnamelen);
+			}
+
+			if ((procname = (char*)calloc(procnamelen + 1, sizeof(char)))) {
+				if (snprintf(procname, procnamelen + 1, "%s", pathname) < 1) {
+					upsdebug_with_errno(3, "%s: failed to snprintf procname: WIN32-like", __func__);
+				} else {
+					goto finish;
+				}
+			} else {
+				upsdebug_with_errno(3, "%s: failed to allocate the procname "
+					"string to store token from WIN32 size %" PRIuSIZE,
+					__func__, procnamelen);
+			}
+
+			/* Fall through to try /proc etc. if available */
+		} else {
+			LPVOID WinBuf;
+			DWORD WinErr = GetLastError();
+			FormatMessage(
+				FORMAT_MESSAGE_MAX_WIDTH_MASK |
+				FORMAT_MESSAGE_ALLOCATE_BUFFER |
+				FORMAT_MESSAGE_FROM_SYSTEM |
+				FORMAT_MESSAGE_IGNORE_INSERTS,
+				NULL,
+				WinErr,
+				MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+				(LPTSTR) &WinBuf,
+				0, NULL );
+
+			upsdebugx(3, "%s: failed to get WIN32 process info: %s",
+				__func__, (char *)WinBuf);
+			LocalFree(WinBuf);
+		}
+	}
+#endif
+
+	if (stat("/proc", &st) == 0 && ((st.st_mode & S_IFMT) == S_IFDIR)) {
+		upsdebugx(3, "%s: /proc is an accessible directory, investigating", __func__);
+
+#if (defined HAVE_READLINK) && HAVE_READLINK
+		/* Linux-like */
+		if (snprintf(pathname, sizeof(pathname), "/proc/%" PRIuMAX "/exe", (uintmax_t)pid) < 10) {
+			upsdebug_with_errno(3, "%s: failed to snprintf pathname: Linux-like", __func__);
+			goto finish;
+		}
+
+		if (lstat(pathname, &st) == 0) {
+			goto process_stat_symlink;
+		}
+
+		/* FreeBSD-like */
+		if (snprintf(pathname, sizeof(pathname), "/proc/%" PRIuMAX "/file", (uintmax_t)pid) < 10) {
+			upsdebug_with_errno(3, "%s: failed to snprintf pathname: FreeBSD-like", __func__);
+			goto finish;
+		}
+
+		if (lstat(pathname, &st) == 0) {
+			goto process_stat_symlink;
+		}
+
+		goto process_parse_file;
+
+process_stat_symlink:
+		upsdebugx(3, "%s: located symlink for PID %" PRIuMAX " at: %s",
+			__func__, (uintmax_t)pid, pathname);
+		/* Some magic symlinks under (for example) /proc and /sys
+		 * report 'st_size' as zero. In that case, take PATH_MAX
+		 * or equivalent as a "good enough" estimate. */
+		if (st.st_size) {
+			/* Add one for ending '\0' */
+			procnamelen = st.st_size + 1;
+		} else {
+			procnamelen = sizeof(pathname);
+		}
+
+		/* Not xcalloc() here, not too fatal if we fail */
+		procname = (char*)calloc(procnamelen, sizeof(char));
+		if (procname) {
+			int nbytes = readlink(pathname, procname, procnamelen);
+			if (nbytes < 0) {
+				upsdebug_with_errno(1, "%s: failed to readlink() from %s",
+					__func__, pathname);
+				free(procname);
+				procname = NULL;
+				goto process_parse_file;
+			}
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+			if ((unsigned int)nbytes > SIZE_MAX || procnamelen <= (size_t)nbytes) {
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) )
+# pragma GCC diagnostic pop
+#endif
+				upsdebugx(1, "%s: failed to readlink() from %s: may have been truncated",
+					__func__, pathname);
+				free(procname);
+				procname = NULL;
+				goto process_parse_file;
+			}
+
+			/* Got a useful reply */
+			procname[nbytes] = '\0';
+			goto finish;
+		} else {
+			upsdebug_with_errno(3, "%s: failed to allocate the procname string "
+				"to readlink() size %" PRIuSIZE, __func__, procnamelen);
+			goto finish;
+		}
+#else
+		upsdebugx(3, "%s: this platform does not have readlink(), skipping this method", __func__);
+		goto process_parse_file;
+#endif	/* HAVE_READLINK */
+
+process_parse_file:
+		upsdebugx(5, "%s: try to parse some files under /proc", __func__);
+
+		/* Check /proc/NNN/cmdline (may start with a '-' to ignore, for
+		 * a title string like "-bash" where programs edit their argv[0]
+		 * (Linux-like OSes at least). Inspired by
+		 * https://gist.github.com/evanslai/30c6d588a80222f665f10b4577dadd61
+		 */
+		if (snprintf(pathname, sizeof(pathname), "/proc/%" PRIuMAX "/cmdline", (uintmax_t)pid) < 10) {
+			upsdebug_with_errno(3, "%s: failed to snprintf pathname: Linux-like", __func__);
+			goto finish;
+		}
+
+		if (stat(pathname, &st) == 0) {
+			FILE* fp = fopen(pathname, "r");
+			if (fp) {
+				char	buf[sizeof(pathname)];
+				if (fgets(buf, sizeof(buf), fp) != NULL) {
+					/* check the first token in the file, the program name */
+					char* first = strtok(buf, " ");
+
+					fclose(fp);
+					if (first) {
+						if (*first == '-')
+							first++;
+
+						/* Not xcalloc() here, not too fatal if we fail */
+						if ((procnamelen = strlen(first))) {
+							upsdebugx(3, "%s: try to parse some files under /proc: processing %s",
+								__func__, pathname);
+							if ((procname = (char*)calloc(procnamelen + 1, sizeof(char)))) {
+								if (snprintf(procname, procnamelen + 1, "%s", first) < 1) {
+									upsdebug_with_errno(3, "%s: failed to snprintf procname: Linux-like", __func__);
+								}
+							} else {
+								upsdebug_with_errno(3, "%s: failed to allocate the procname "
+									"string to store token from 'cmdline' size %" PRIuSIZE,
+									__func__, procnamelen);
+							}
+
+							goto finish;
+						}
+					}
+				} else {
+					fclose(fp);
+				}
+			}
+		}
+
+		/* Check /proc/NNN/stat (second token, in parentheses, may be truncated)
+		 * see e.g. https://stackoverflow.com/a/12675103/4715872 */
+		if (snprintf(pathname, sizeof(pathname), "/proc/%" PRIuMAX "/stat", (uintmax_t)pid) < 10) {
+			upsdebug_with_errno(3, "%s: failed to snprintf pathname: Linux-like", __func__);
+			goto finish;
+		}
+
+		if (stat(pathname, &st) == 0) {
+			FILE* fp = fopen(pathname, "r");
+			if (fp) {
+				long	spid;
+				char	sstate;
+				char	buf[sizeof(pathname)];
+
+				memset (buf, 0, sizeof(buf));
+				if ( (fscanf(fp, "%ld (%[^)]) %c", &spid, buf, &sstate)) == 3 ) {
+					/* Some names can be pretty titles like "init(Ubuntu)"
+					 * or "Relay(223)". Or truncated like "docker-desktop-".
+					 * Tokenize by "(" " " and extract the first token to
+					 * address the former "problem", not too much we can
+					 * do about the latter except for keeping NUT program
+					 * names concise.
+					 */
+					char* first = strtok(buf, "( ");
+
+					fclose(fp);
+					if (first) {
+						/* Not xcalloc() here, not too fatal if we fail */
+						if ((procnamelen = strlen(first))) {
+							upsdebugx(3, "%s: try to parse some files under /proc: processing %s "
+								"(WARNING: may be truncated)",
+								__func__, pathname);
+							if ((procname = (char*)calloc(procnamelen + 1, sizeof(char)))) {
+								if (snprintf(procname, procnamelen + 1, "%s", first) < 1) {
+									upsdebug_with_errno(3, "%s: failed to snprintf procname: Linux-like", __func__);
+								}
+							} else {
+								upsdebug_with_errno(3, "%s: failed to allocate the procname "
+									"string to store token from 'stat' size %" PRIuSIZE,
+									__func__, procnamelen);
+							}
+
+							goto finish;
+						}
+					}
+				} else {
+					fclose(fp);
+				}
+			}
+		}
+
+#if defined(HAVE_LIB_ILLUMOS_PROC) && HAVE_LIB_ILLUMOS_PROC
+		/* Solaris/illumos: parse binary structure at /proc/NNN/psinfo */
+		if (snprintf(pathname, sizeof(pathname), "/proc/%" PRIuMAX "/psinfo", (uintmax_t)pid) < 10) {
+			upsdebug_with_errno(3, "%s: failed to snprintf pathname: Solaris/illumos-like", __func__);
+			goto finish;
+		}
+
+		if (stat(pathname, &st) == 0) {
+			FILE* fp = fopen(pathname, "r");
+			if (!fp) {
+				upsdebug_with_errno(3, "%s: try to parse '%s':"
+					"fopen() returned NULL", __func__, pathname);
+			} else {
+				psinfo_t	info;	/* process information from /proc */
+				size_t	r;
+
+				memset (&info, 0, sizeof(info));
+				r = fread((char *)&info, sizeof (info), 1, fp);
+				if (r != 1) {
+					upsdebug_with_errno(3, "%s: try to parse '%s': "
+						"unexpected read size: got %" PRIuSIZE
+						" record(s) from file of size %" PRIuMAX
+						" vs. 1 piece of %" PRIuSIZE " struct size",
+						__func__, pathname, r,
+						(uintmax_t)st.st_size, sizeof (info));
+					fclose(fp);
+				} else {
+					fclose(fp);
+
+					/* Not xcalloc() here, not too fatal if we fail */
+					if ((procnamelen = strlen(info.pr_fname))) {
+						upsdebugx(3, "%s: try to parse some files under /proc: processing %s",
+							__func__, pathname);
+						if ((procname = (char*)calloc(procnamelen + 1, sizeof(char)))) {
+							if (snprintf(procname, procnamelen + 1, "%s", info.pr_fname) < 1) {
+								upsdebug_with_errno(3, "%s: failed to snprintf pathname: Solaris/illumos-like", __func__);
+							}
+						} else {
+							upsdebug_with_errno(3, "%s: failed to allocate the procname "
+								"string to store token from 'psinfo' size %" PRIuSIZE,
+								__func__, procnamelen);
+						}
+
+						goto finish;
+					}
+				}
+			}
+		}
+#endif
+	} else {
+		upsdebug_with_errno(3, "%s: /proc is not a directory or not accessible", __func__);
+	}
+
+#if defined(HAVE_LIB_BSD_KVM_PROC) && HAVE_LIB_BSD_KVM_PROC
+	/* OpenBSD, maybe other BSD: no /proc; use API call, see ps.c link above and
+	 * https://kaashif.co.uk/2015/06/18/how-to-get-a-list-of-processes-on-openbsd-in-c/
+	 */
+	if (!procname) {
+		char	errbuf[_POSIX2_LINE_MAX];
+		kvm_t	*kd = kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf);
+
+		upsdebugx(3, "%s: try to parse BSD KVM process info snapsnot", __func__);
+		if (!kd) {
+			upsdebugx(3, "%s: try to parse BSD KVM process info snapsnot: "
+				"kvm_openfiles() returned NULL", __func__);
+		} else {
+			int	nentries = 0;
+			struct	kinfo_proc *kp = kvm_getprocs(kd, KERN_PROC_PID, pid, sizeof(*kp), &nentries);
+
+			if (!kp) {
+				upsdebugx(3, "%s: try to parse BSD KVM process info snapsnot: "
+					"kvm_getprocs() returned NULL", __func__);
+			} else {
+				int	i;
+				if (nentries != 1)
+					upsdebugx(3, "%s: expected to get 1 reply from BSD kvm_getprocs but got %d",
+						__func__, nentries);
+				for (i = 0; i < nentries; i++) {
+					upsdebugx(5, "%s: processing reply #%d from BSD"
+						" kvm_getprocs: pid=%" PRIuMAX " name='%s'",
+						__func__, i, (uintmax_t)kp[i].p_pid, kp[i].p_comm);
+					if ((uintmax_t)(kp[i].p_pid) == (uintmax_t)pid) {
+						/* Not xcalloc() here, not too fatal if we fail */
+						if ((procnamelen = strlen(kp[i].p_comm))) {
+							if ((procname = (char*)calloc(procnamelen + 1, sizeof(char)))) {
+								if (snprintf(procname, procnamelen + 1, "%s", kp[i].p_comm) < 1) {
+									upsdebug_with_errno(3, "%s: failed to snprintf procname: BSD-like", __func__);
+								}
+							} else {
+								upsdebug_with_errno(3, "%s: failed to allocate the procname "
+									"string to store token from BSD KVM process info "
+									"snapsnot size %" PRIuSIZE,
+									__func__, procnamelen);
+							}
+
+							goto finish;
+						}
+					}
+				}
+			}
+		}
+	}
+#endif	/* HAVE_LIB_BSD_KVM_PROC */
+
+	goto finish;
+
+finish:
+	if (procname) {
+		procnamelen = strlen(procname);
+		if (procnamelen == 0) {
+			free(procname);
+			procname = NULL;
+		} else {
+			upsdebugx(1, "%s: determined process name for PID %" PRIuMAX ": %s",
+				__func__, (uintmax_t)pid, procname);
+		}
+	}
+
+	if (!procname) {
+		upsdebugx(1, "%s: failed to determine process name for PID %" PRIuMAX,
+			__func__, (uintmax_t)pid);
+	}
+
+	return procname;
+}
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_BESIDEFUNC) && (!defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP_INSIDEFUNC) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS_BESIDEFUNC) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE_BESIDEFUNC) )
+# pragma GCC diagnostic pop
+#endif
+
+size_t parseprogbasename(char *buf, size_t buflen, const char *progname, size_t *pprogbasenamelen, size_t *pprogbasenamedot)
+{
+	size_t	i,
+		progbasenamelen = 0,
+		progbasenamedot = 0;
+
+	if (pprogbasenamelen)
+		*pprogbasenamelen = 0;
+
+	if (pprogbasenamedot)
+		*pprogbasenamedot = 0;
+
+	if (!buf || !progname || !buflen || progname[0] == '\0')
+		return 0;
+
+	for (i = 0; i < buflen && progname[i] != '\0'; i++) {
+		if (progname[i] == '/'
+#ifdef WIN32
+		||  progname[i] == '\\'
+#endif
+		) {
+			progbasenamelen = 0;
+			progbasenamedot = 0;
+			continue;
+		}
+
+		if (progname[i] == '.')
+			progbasenamedot = progbasenamelen;
+
+		buf[progbasenamelen++] = progname[i];
+	}
+	buf[progbasenamelen] = '\0';
+	buf[buflen - 1] = '\0';
+
+	if (pprogbasenamelen)
+		*pprogbasenamelen = progbasenamelen;
+
+	if (pprogbasenamedot)
+		*pprogbasenamedot = progbasenamedot;
+
+	return progbasenamelen;
+}
+
+int checkprocname_ignored(const char *caller)
 {
-#ifndef WIN32
-	/* if we can't switch users, then don't even try */
-	intmax_t initial_uid = getuid();
-	intmax_t initial_euid = geteuid();
+	char	*s = NULL;
 
-	if (!pw) {
-		upsdebugx(1, "Can not become_user(<null>), skipped");
-		return;
+	if ((s = getenv("NUT_IGNORE_CHECKPROCNAME"))) {
+		/* FIXME: Make server/conf.c::parse_boolean() reusable */
+		if ( (!strcasecmp(s, "true")) || (!strcasecmp(s, "on")) || (!strcasecmp(s, "yes")) || (!strcasecmp(s, "1"))) {
+			upsdebugx(1, "%s for %s: skipping because caller set NUT_IGNORE_CHECKPROCNAME", __func__, NUT_STRARG(caller));
+			return 1;
+		}
 	}
 
-	if ((initial_euid != 0) && (initial_uid != 0)) {
-		intmax_t initial_gid = getgid();
-		if (initial_euid == (intmax_t)pw->pw_uid
-		||   initial_uid == (intmax_t)pw->pw_uid
+	return 0;
+}
+
+int compareprocname(pid_t pid, const char *procname, const char *progname)
+{
+	/* Given the binary path name of (presumably) a running process,
+	 * check if it matches the assumed name of the current program.
+	 * The "pid" value is used in log reporting.
+	 * Returns:
+	 *	-3	Skipped because NUT_IGNORE_CHECKPROCNAME is set
+	 *	-2	Could not parse a program name (ok to proceed,
+	 *		risky - but matches legacy behavior)
+	 *	-1	Could not identify a program name (ok to proceed,
+	 *		risky - but matches legacy behavior)
+	 *	0	Process name identified, does not seem to match
+	 *	1+	Process name identified, and seems to match with
+	 *		varying precision
+	 * Generally speaking, if (compareprocname(...)) then ok to proceed
+	 */
+
+	int	ret = -127;
+	size_t	procbasenamelen = 0, progbasenamelen = 0;
+	/* Track where the last dot is in the basename; 0 means none */
+	size_t	procbasenamedot = 0, progbasenamedot = 0;
+#ifdef UNIX_PATH_MAX
+	char	procbasename[UNIX_PATH_MAX], progbasename[UNIX_PATH_MAX];
+#else
+	char	procbasename[PATH_MAX], progbasename[PATH_MAX];
+#endif
+
+	if (checkprocname_ignored(__func__)) {
+		ret = -3;
+		goto finish;
+	}
+
+	if (!procname || !progname) {
+		ret = -1;
+		goto finish;
+	}
+
+	/* First quickly try for an exact hit (possible dir names included) */
+	if (!strcmp(procname, progname)) {
+		ret = 1;
+		goto finish;
+	}
+
+	/* Parse the basenames apart */
+	if (!parseprogbasename(progbasename, sizeof(progbasename), progname, &progbasenamelen, &progbasenamedot)
+	||  !parseprogbasename(procbasename, sizeof(procbasename), procname, &procbasenamelen, &procbasenamedot)
+	) {
+		ret = -2;
+		goto finish;
+	}
+
+	/* First quickly try for an exact hit of base names */
+	if (progbasenamelen == procbasenamelen && progbasenamedot == procbasenamedot && !strcmp(procbasename, progbasename)) {
+		ret = 2;
+		goto finish;
+	}
+
+	/* Check for executable program filename extensions and/or case-insensitive
+	 * matching on some platforms */
+#ifdef WIN32
+	if (!strcasecmp(procname, progname)) {
+		ret = 3;
+		goto finish;
+	}
+
+	if (!strcasecmp(procbasename, progbasename)) {
+		ret = 4;
+		goto finish;
+	}
+
+	if (progbasenamedot == procbasenamedot || !progbasenamedot || !procbasenamedot) {
+		/* Same base name before ext, maybe different casing or absence of ext in one of them */
+		size_t	dot = progbasenamedot ? progbasenamedot : procbasenamedot;
+
+		if (!strncasecmp(progbasename, procbasename, dot - 1) &&
+		     (  (progbasenamedot && !strcasecmp(progbasename + progbasenamedot, ".exe"))
+		     || (procbasenamedot && !strcasecmp(procbasename + procbasenamedot, ".exe")) )
 		) {
-			upsdebugx(1, "No need to become_user(%s): "
-				"already UID=%jd GID=%jd",
-				pw->pw_name, initial_uid, initial_gid);
-		} else {
-			upsdebugx(1, "Can not become_user(%s): "
-				"not root initially, "
-				"remaining UID=%jd GID=%jd",
-				pw->pw_name, initial_uid, initial_gid);
+			ret = 5;
+			goto finish;
 		}
-		return;
 	}
+#endif
 
-	if (initial_uid == 0)
-		if (seteuid(0))
-			fatal_with_errno(EXIT_FAILURE, "getuid gave 0, but seteuid(0) failed");
+	/* TOTHINK: Developer builds wrapped with libtool may be prefixed
+	 * by "lt-" in the filename. Should we re-enter (or wrap around)
+	 * this search with a set of variants with/without the prefix on
+	 * both sides?..
+	 */
 
-	if (initgroups(pw->pw_name, pw->pw_gid) == -1)
-		fatal_with_errno(EXIT_FAILURE, "initgroups");
+	/* Nothing above has matched */
+	ret = 0;
+
+finish:
+	switch (ret) {
+		case 5:
+			upsdebugx(1,
+				"%s: case-insensitive base name hit with "
+				"an executable program extension involved for "
+				"PID %" PRIuMAX " of '%s'=>'%s' and checked "
+				"'%s'=>'%s'",
+				__func__, (uintmax_t)pid,
+				procname, procbasename,
+				progname, progbasename);
+			break;
 
-	if (setgid(pw->pw_gid) == -1)
-		fatal_with_errno(EXIT_FAILURE, "setgid");
+		case 4:
+			upsdebugx(1,
+				"%s: case-insensitive base name hit for PID %"
+				PRIuMAX " of '%s'=>'%s' and checked '%s'=>'%s'",
+				__func__, (uintmax_t)pid,
+				procname, procbasename,
+				progname, progbasename);
+			break;
 
-	if (setuid(pw->pw_uid) == -1)
-		fatal_with_errno(EXIT_FAILURE, "setuid");
+		case 3:
+			upsdebugx(1,
+				"%s: case-insensitive full name hit for PID %"
+				PRIuMAX " of '%s' and checked '%s'",
+				__func__, (uintmax_t)pid, procname, progname);
+			break;
 
-	upsdebugx(1, "Succeeded to become_user(%s): now UID=%jd GID=%jd",
-		pw->pw_name, (intmax_t)getuid(), (intmax_t)getgid());
-#else
-	upsdebugx(1, "Can not become_user(%s): not implemented on this platform",
-		pw ? pw->pw_name : "<null>");
-#endif
+		case 2:
+			upsdebugx(1,
+				"%s: case-sensitive base name hit for PID %"
+				PRIuMAX " of '%s'=>'%s' and checked '%s'=>'%s'",
+				__func__, (uintmax_t)pid,
+				procname, procbasename,
+				progname, progbasename);
+			break;
+
+		case 1:
+			upsdebugx(1,
+				"%s: exact case-sensitive full name hit for PID %"
+				PRIuMAX " of '%s' and checked '%s'",
+				__func__, (uintmax_t)pid, procname, progname);
+			break;
+
+		case 0:
+			upsdebugx(1,
+				"%s: did not find any match of program names "
+				"for PID %" PRIuMAX " of '%s'=>'%s' and checked "
+				"'%s'=>'%s'",
+				__func__, (uintmax_t)pid,
+				procname, procbasename,
+				progname, progbasename);
+			break;
+
+		case -1:
+			/* failed to getprocname(), logged above in it */
+			break;
+
+		case -2:
+			upsdebugx(1,
+				"%s: failed to parse base names of the programs",
+				__func__);
+			break;
+
+		case -3:
+			/* skipped due to envvar, logged above */
+			break;
+
+		default:
+			upsdebugx(1,
+				"%s: unexpected result looking for process name "
+				"of PID %" PRIuMAX ": %d",
+				__func__, (uintmax_t)pid, ret);
+			ret = -127;
+			break;
+	}
+
+	return ret;
 }
 
-/* drop down into a directory and throw away pointers to the old path */
-void chroot_start(const char *path)
+int checkprocname(pid_t pid, const char *progname)
 {
-	if (chdir(path))
-		fatal_with_errno(EXIT_FAILURE, "chdir(%s)", path);
+	/* If we can determine the binary path name of the specified "pid",
+	 * check if it matches the assumed name of the current program.
+	 * Returns: same as compareprocname()
+	 * Generally speaking, if (checkprocname(...)) then ok to proceed
+	 */
+	char	*procname = NULL;
+	int	ret = 0;
 
-#ifndef WIN32
-	if (chroot(path))
-		fatal_with_errno(EXIT_FAILURE, "chroot(%s)", path);
+	/* Quick skip before drilling into getprocname() */
+	if (checkprocname_ignored(__func__)) {
+		ret = -3;
+		goto finish;
+	}
 
-#else
-	upsdebugx(1, "Can not chroot into %s: not implemented on this platform", path);
-#endif
+	if (!progname) {
+		ret = -1;
+		goto finish;
+	}
 
-	if (chdir("/"))
-		fatal_with_errno(EXIT_FAILURE, "chdir(/)");
+	procname = getprocname(pid);
+	if (!procname) {
+		ret = -1;
+		goto finish;
+	}
 
-#ifndef WIN32
-	upsdebugx(1, "chrooted into %s", path);
-#endif
+	ret = compareprocname(pid, procname, progname);
+
+finish:
+	if (procname)
+		free(procname);
+
+	return ret;
 }
 
 #ifdef WIN32
@@ -430,7 +1645,7 @@ void writepid(const char *name)
 	if (*name == '/')
 		snprintf(fn, sizeof(fn), "%s", name);
 	else
-		snprintf(fn, sizeof(fn), "%s/%s.pid", PIDPATH, name);
+		snprintf(fn, sizeof(fn), "%s/%s.pid", rootpidpath(), name);
 
 	mask = umask(022);
 	pidf = fopen(fn, "w");
@@ -453,23 +1668,161 @@ void writepid(const char *name)
 /* send sig to pid, returns -1 for error, or
  * zero for a successfully sent signal
  */
-int sendsignalpid(pid_t pid, int sig)
+int sendsignalpid(pid_t pid, int sig, const char *progname, int check_current_progname)
 {
 #ifndef WIN32
-	int	ret;
+	int	ret, cpn1 = -10, cpn2 = -10;
+	char	*current_progname = NULL, *procname = NULL;
 
+	/* TOTHINK: What about containers where a NUT daemon *is* the only process
+	 * and is the PID=1 of the container (recycle if dead)? */
 	if (pid < 2 || pid > get_max_pid_t()) {
-		upslogx(LOG_NOTICE,
-			"Ignoring invalid pid number %" PRIdMAX,
-			(intmax_t) pid);
+		if (nut_debug_level > 0 || nut_sendsignal_debug_level > 0)
+			upslogx(LOG_NOTICE,
+				"Ignoring invalid pid number %" PRIdMAX,
+				(intmax_t) pid);
+		return -1;
+	}
+
+	ret = 0;
+	if (!checkprocname_ignored(__func__))
+		procname = getprocname(pid);
+
+	if (procname && progname) {
+		/* Check against some expected (often built-in) name */
+		if (!(cpn1 = compareprocname(pid, procname, progname))) {
+			/* Did not match expected (often built-in) name */
+			ret = -1;
+		} else {
+			if (cpn1 > 0) {
+				/* Matched expected name, ok to proceed */
+				ret = 1;
+			}
+			/* ...else could not determine name of PID; think later */
+		}
+	}
+	/* if (cpn1 == -3) => NUT_IGNORE_CHECKPROCNAME=true */
+	/* if (cpn1 == -1) => could not determine name of PID... retry just in case? */
+	if (procname && ret <= 0 && check_current_progname && cpn1 != -3) {
+		/* NOTE: This could be optimized a bit by pre-finding the procname
+		 * of "pid" and re-using it, but this is not a hot enough code path
+		 * to bother much.
+		 */
+		current_progname = getprocname(getpid());
+		if (current_progname && (cpn2 = compareprocname(pid, procname, current_progname))) {
+			if (cpn2 > 0) {
+				/* Matched current process as asked, ok to proceed */
+				ret = 2;
+			}
+			/* ...else could not determine name of PID; think later */
+		} else {
+			if (current_progname) {
+				/* Did not match current process name */
+				ret = -2;
+			} /* else just did not determine current process
+			   * name, so did not actually check either
+			   * // ret = -3;
+			   */
+		}
+	}
+
+	/* if ret == 0, ok to proceed - not asked for any sanity checks;
+	 * if ret > 0, ok to proceed - we had some definitive match above;
+	 * if ret < 0, NOT OK to proceed - we had some definitive fault above
+	 */
+	if (ret < 0) {
+		upsdebugx(1,
+			"%s: ran at least one check, and all such checks "
+			"found a process name for PID %" PRIuMAX " and "
+			"failed to match: "
+			"found procname='%s', "
+			"expected progname='%s' (res=%d%s), "
+			"current progname='%s' (res=%d%s)",
+			__func__, (uintmax_t)pid,
+			NUT_STRARG(procname),
+			NUT_STRARG(progname), cpn1,
+			(cpn1 == -10 ? ": did not check" : ""),
+			NUT_STRARG(current_progname), cpn2,
+			(cpn2 == -10 ? ": did not check" : ""));
+
+		if (nut_debug_level > 0 || nut_sendsignal_debug_level > 1) {
+			switch (ret) {
+				case -1:
+					upslogx(LOG_ERR, "Tried to signal PID %" PRIuMAX
+						" which exists but is not of"
+						" expected program '%s'; not asked"
+						" to cross-check current PID's name",
+						(uintmax_t)pid, progname);
+					break;
+
+				/* Maybe we tried both data sources, maybe just current_progname */
+				case -2:
+				/*case -3:*/
+					if (progname && current_progname) {
+						/* Tried both, downgraded verdict further */
+						upslogx(LOG_ERR, "Tried to signal PID %" PRIuMAX
+							" which exists but is not of expected"
+							" program '%s' nor current '%s'",
+							(uintmax_t)pid, progname, current_progname);
+					} else if (current_progname) {
+						/* Not asked for progname==NULL */
+						upslogx(LOG_ERR, "Tried to signal PID %" PRIuMAX
+							" which exists but is not of"
+							" current program '%s'",
+							(uintmax_t)pid, current_progname);
+					} else if (progname) {
+						upslogx(LOG_ERR, "Tried to signal PID %" PRIuMAX
+							" which exists but is not of"
+							" expected program '%s'; could not"
+							" cross-check current PID's name",
+							(uintmax_t)pid, progname);
+					} else {
+						/* Both NULL; one not asked, another not detected;
+						 * should not actually get here (wannabe `ret==-3`)
+						 */
+						upslogx(LOG_ERR, "Tried to signal PID %" PRIuMAX
+							" but could not cross-check current PID's"
+							" name: did not expect to get here",
+							(uintmax_t)pid);
+					}
+					break;
+
+				default:
+					break;
+			}
+		}
+
+		if (current_progname) {
+			free(current_progname);
+			current_progname = NULL;
+		}
+
+		if (procname) {
+			free(procname);
+			procname = NULL;
+		}
+
+		/* Logged or not, sanity-check was requested and failed */
 		return -1;
 	}
 
-	/* see if this is going to work first - does the process exist? */
+	if (current_progname) {
+		free(current_progname);
+		current_progname = NULL;
+	}
+
+	if (procname) {
+		free(procname);
+		procname = NULL;
+	}
+
+	/* see if this is going to work first - does the process exist,
+	 * and do we have permissions to signal it? */
 	ret = kill(pid, 0);
 
 	if (ret < 0) {
-		perror("kill");
+		if (nut_debug_level > 0 || nut_sendsignal_debug_level >= NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING)
+			perror("kill");
 		return -1;
 	}
 
@@ -478,7 +1831,8 @@ int sendsignalpid(pid_t pid, int sig)
 		ret = kill(pid, sig);
 
 		if (ret < 0) {
-			perror("kill");
+			if (nut_debug_level > 0 || nut_sendsignal_debug_level > 1)
+				perror("kill");
 			return -1;
 		}
 	}
@@ -487,6 +1841,9 @@ int sendsignalpid(pid_t pid, int sig)
 #else
 	NUT_UNUSED_VARIABLE(pid);
 	NUT_UNUSED_VARIABLE(sig);
+	NUT_UNUSED_VARIABLE(progname);
+	NUT_UNUSED_VARIABLE(check_current_progname);
+	/* Windows builds use named pipes, not signals per se */
 	upslogx(LOG_ERR,
 		"%s: not implemented for Win32 and "
 		"should not have been called directly!",
@@ -503,8 +1860,10 @@ pid_t parsepid(const char *buf)
 	pid_t	pid = -1;
 	intmax_t	_pid;
 
+	errno = 0;
 	if (!buf) {
 		upsdebugx(6, "%s: called with NULL input", __func__);
+		errno = EINVAL;
 		return pid;
 	}
 
@@ -513,36 +1872,48 @@ pid_t parsepid(const char *buf)
 	if (_pid <= get_max_pid_t()) {
 		pid = (pid_t)_pid;
 	} else {
-		upslogx(LOG_NOTICE, "Received a pid number too big for a pid_t: %" PRIdMAX, _pid);
+		errno = ERANGE;
+
+		if (nut_debug_level > 0 || nut_sendsignal_debug_level > 0)
+			upslogx(LOG_NOTICE,
+				"Received a pid number too big for a pid_t: %"
+				PRIdMAX, _pid);
 	}
 
 	return pid;
 }
 
-/* open pidfn, get the pid, then send it sig
+/* open pidfn, get the pid;
  * returns negative codes for errors, or
- * zero for a successfully sent signal
+ * zero for a successfully discovered value
  */
-#ifndef WIN32
-int sendsignalfn(const char *pidfn, int sig)
+pid_t parsepidfile(const char *pidfn)
 {
 	char	buf[SMALLBUF];
 	FILE	*pidf;
 	pid_t	pid = -1;
-	int	ret = -1;
 
 	pidf = fopen(pidfn, "r");
 	if (!pidf) {
-		upslog_with_errno(LOG_NOTICE, "fopen %s", pidfn);
+		/* This one happens quite often when a daemon starts
+		 * for the first time and no opponent PID file exists,
+		 * so the cut-off verbosity is higher.
+		 */
+		if (nut_debug_level > 0 ||
+		    nut_sendsignal_debug_level >= NUT_SENDSIGNAL_DEBUG_LEVEL_FOPEN_PIDFILE)
+			upslog_with_errno(LOG_NOTICE, "fopen %s", pidfn);
 		return -3;
 	}
 
 	if (fgets(buf, sizeof(buf), pidf) == NULL) {
-		upslogx(LOG_NOTICE, "Failed to read pid from %s", pidfn);
+		if (nut_debug_level > 0 || nut_sendsignal_debug_level > 2)
+			upslogx(LOG_NOTICE, "Failed to read pid from %s", pidfn);
 		fclose(pidf);
 		return -2;
 	}
-	/* TOTHINK: Original code only closed pidf before
+
+	/* TOTHINK: Original sendsignalfn code (which this
+	 * was extracted from) only closed pidf before
 	 * exiting the method, on error or "normally".
 	 * Why not here? Do we want an (exclusive?) hold
 	 * on it while being active in the method?
@@ -551,20 +1922,36 @@ int sendsignalfn(const char *pidfn, int sig)
 	/* this method actively reports errors, if any */
 	pid = parsepid(buf);
 
+	fclose(pidf);
+
+	return pid;
+}
+
+/* open pidfn, get the pid, then send it sig
+ * returns negative codes for errors, or
+ * zero for a successfully sent signal
+ */
+#ifndef WIN32
+int sendsignalfn(const char *pidfn, int sig, const char *progname, int check_current_progname)
+{
+	int	ret = -1;
+	pid_t	pid = parsepidfile(pidfn);
+
 	if (pid >= 0) {
 		/* this method actively reports errors, if any */
-		ret = sendsignalpid(pid, sig);
+		ret = sendsignalpid(pid, sig, progname, check_current_progname);
 	}
 
-	fclose(pidf);
 	return ret;
 }
 
 #else	/* => WIN32 */
 
-int sendsignalfn(const char *pidfn, const char * sig)
+int sendsignalfn(const char *pidfn, const char * sig, const char *progname_ignored, int check_current_progname_ignored)
 {
 	BOOL	ret;
+	NUT_UNUSED_VARIABLE(progname_ignored);
+	NUT_UNUSED_VARIABLE(check_current_progname_ignored);
 
 	ret = send_to_named_pipe(pidfn, sig);
 
@@ -627,18 +2014,21 @@ int snprintfcat(char *dst, size_t size, const char *fmt, ...)
 
 /* lazy way to send a signal if the program uses the PIDPATH */
 #ifndef WIN32
-int sendsignal(const char *progname, int sig)
+int sendsignal(const char *progname, int sig, int check_current_progname)
 {
 	char	fn[SMALLBUF];
 
-	snprintf(fn, sizeof(fn), "%s/%s.pid", PIDPATH, progname);
+	snprintf(fn, sizeof(fn), "%s/%s.pid", rootpidpath(), progname);
 
-	return sendsignalfn(fn, sig);
+	return sendsignalfn(fn, sig, progname, check_current_progname);
 }
 #else
-int sendsignal(const char *progname, const char * sig)
+int sendsignal(const char *progname, const char * sig, int check_current_progname)
 {
-	return sendsignalfn(progname, sig);
+	/* progname is used as the pipe name for WIN32
+	 * check_current_progname is de-facto ignored
+	 */
+	return sendsignalfn(progname, sig, NULL, check_current_progname);
 }
 #endif
 
@@ -846,9 +2236,15 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 		va_end(va);
 
 		if ((ret < 0) || (ret >= (int) sizeof(msgbuf))) {
-			syslog(LOG_WARNING,
-				"%s (%s:%d): vsnprintf needed more than %" PRIuSIZE " bytes: %d",
-				__func__, __FILE__, __LINE__, sizeof(msgbuf), ret);
+			if (syslog_is_disabled()) {
+				fprintf(stderr,
+					"%s (%s:%d): vsnprintf needed more than %" PRIuSIZE " bytes: %d",
+					__func__, __FILE__, __LINE__, sizeof(msgbuf), ret);
+			} else {
+				syslog(LOG_WARNING,
+					"%s (%s:%d): vsnprintf needed more than %" PRIuSIZE " bytes: %d",
+					__func__, __FILE__, __LINE__, sizeof(msgbuf), ret);
+			}
 		} else {
 			msglen = strlen(msgbuf);
 		}
@@ -866,7 +2262,7 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 			"skipped for libcommonclient build, "
 			"will not spam more about it", __func__, state);
 	upsnotify_reported_disabled_systemd = 1;
-# else
+# else	/* not WITHOUT_LIBSYSTEMD */
 	if (!getenv("NOTIFY_SOCKET")) {
 		if (!upsnotify_reported_disabled_systemd)
 			upsdebugx(upsnotify_report_verbosity,
@@ -884,9 +2280,15 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 			usec_t monots = timespec_load(&monoclock_ts);
 			ret = snprintf(monoclock_str + 1, sizeof(monoclock_str) - 1, "MONOTONIC_USEC=%" PRI_USEC, monots);
 			if ((ret < 0) || (ret >= (int) sizeof(monoclock_str) - 1)) {
-				syslog(LOG_WARNING,
-					"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
-					__func__, __FILE__, __LINE__, sizeof(monoclock_str), ret);
+				if (syslog_is_disabled()) {
+					fprintf(stderr,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(monoclock_str), ret);
+				} else {
+					syslog(LOG_WARNING,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(monoclock_str), ret);
+				}
 				msglen = 0;
 			} else {
 				monoclock_str[0] = '\n';
@@ -903,9 +2305,15 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 		if (msglen) {
 			ret = snprintf(buf, sizeof(buf), "STATUS=%s", msgbuf);
 			if ((ret < 0) || (ret >= (int) sizeof(buf))) {
-				syslog(LOG_WARNING,
-					"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
-					__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				if (syslog_is_disabled()) {
+					fprintf(stderr,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				} else {
+					syslog(LOG_WARNING,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				}
 				msglen = 0;
 			} else {
 				msglen = (size_t)ret;
@@ -1002,7 +2410,7 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 								"(%" PRIu64 "msec remain)",
 								__func__, postit, to);
 					}
-#   endif
+#   endif	/* HAVE_SD_WATCHDOG_ENABLED */
 
 					if (postit < 1) {
 						char *s = getenv("WATCHDOG_USEC");
@@ -1098,9 +2506,15 @@ int upsnotify(upsnotify_state_t state, const char *fmt, ...)
 		if ((ret < 0) || (ret >= (int) sizeof(buf))) {
 			/* Refusal to send the watchdog ping is not an error to report */
 			if ( !(ret == -126 && (state == NOTIFY_STATE_WATCHDOG)) ) {
-				syslog(LOG_WARNING,
-					"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
-					__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				if (syslog_is_disabled()) {
+					fprintf(stderr,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				} else {
+					syslog(LOG_WARNING,
+						"%s (%s:%d): snprintf needed more than %" PRIuSIZE " bytes: %d",
+						__func__, __FILE__, __LINE__, sizeof(buf), ret);
+				}
 			}
 			ret = -1;
 		} else {
@@ -1175,7 +2589,9 @@ void nut_report_config_flags(void)
 	 * Depending on amount of configuration tunables involved by a particular
 	 * build of NUT, the string can be quite long (over 1KB).
 	 */
+#if 0
 	const char *acinit_ver = NULL;
+#endif
 	/* Pass these as variables to avoid warning about never reaching one
 	 * of compiled codepaths: */
 	const char *compiler_ver = CC_VERSION;
@@ -1185,6 +2601,7 @@ void nut_report_config_flags(void)
 	if (nut_debug_level < 1)
 		return;
 
+#if 0
 	/* Only report git revision if NUT_VERSION_MACRO in nut_version.h aka
 	 * UPS_VERSION here is remarkably different from PACKAGE_VERSION from
 	 * configure.ac AC_INIT() -- which may be e.g. "2.8.0.1" although some
@@ -1202,7 +2619,14 @@ void nut_report_config_flags(void)
 		 * especially embedders, tend to place their product IDs here),
 		 * or if PACKAGE_VERSION *is NOT* a substring of it: */
 		acinit_ver = PACKAGE_VERSION;
+/*
+		// Triplet that was printed below:
+		(acinit_ver ? " (release/snapshot of " : ""),
+		(acinit_ver ? acinit_ver : ""),
+		(acinit_ver ? ")" : ""),
+*/
 	}
+#endif
 
 	/* NOTE: If changing wording here, keep in sync with configure.ac logic
 	 * looking for CONFIG_FLAGS_DEPLOYED via "configured with flags:" string!
@@ -1220,13 +2644,10 @@ void nut_report_config_flags(void)
 	}
 
 	if (xbit_test(upslog_flags, UPSLOG_STDERR)) {
-		fprintf(stderr, "%4.0f.%06ld\t[D1] Network UPS Tools version %s%s%s%s%s%s%s %s%s\n",
+		fprintf(stderr, "%4.0f.%06ld\t[D1] Network UPS Tools version %s%s%s%s %s%s\n",
 			difftime(now.tv_sec, upslog_start.tv_sec),
 			(long)(now.tv_usec - upslog_start.tv_usec),
-			UPS_VERSION,
-			(acinit_ver ? " (release/snapshot of " : ""),
-			(acinit_ver ? acinit_ver : ""),
-			(acinit_ver ? ")" : ""),
+			describe_NUT_VERSION_once(),
 			(compiler_ver && *compiler_ver != '\0' ? " built with " : ""),
 			(compiler_ver && *compiler_ver != '\0' ? compiler_ver : ""),
 			(compiler_ver && *compiler_ver != '\0' ? " and" : ""),
@@ -1240,18 +2661,16 @@ void nut_report_config_flags(void)
 
 	/* NOTE: May be ignored or truncated by receiver if that syslog server
 	 * (and/or OS sender) does not accept messages of such length */
-	if (xbit_test(upslog_flags, UPSLOG_SYSLOG))
-		syslog(LOG_DEBUG, "Network UPS Tools version %s%s%s%s%s%s%s %s%s",
-			UPS_VERSION,
-			(acinit_ver ? " (release/snapshot of " : ""),
-			(acinit_ver ? acinit_ver : ""),
-			(acinit_ver ? ")" : ""),
+	if (xbit_test(upslog_flags, UPSLOG_SYSLOG)) {
+		syslog(LOG_DEBUG, "Network UPS Tools version %s%s%s%s %s%s",
+			describe_NUT_VERSION_once(),
 			(compiler_ver && *compiler_ver != '\0' ? " built with " : ""),
 			(compiler_ver && *compiler_ver != '\0' ? compiler_ver : ""),
 			(compiler_ver && *compiler_ver != '\0' ? " and" : ""),
 			(config_flags && *config_flags != '\0' ? "configured with flags: " : "configured all by default guesswork"),
 			(config_flags && *config_flags != '\0' ? config_flags : "")
 		);
+	}
 }
 
 static void vupslog(int priority, const char *fmt, va_list va, int use_strerror)
@@ -1335,10 +2754,17 @@ static void vupslog(int priority, const char *fmt, va_list va, int use_strerror)
 		/* Arbitrary limit, gotta stop somewhere */
 		if (bufsize > LARGEBUF * 64) {
 vupslog_too_long:
-			syslog(LOG_WARNING, "vupslog: vsnprintf needed "
-				"more than %" PRIuSIZE " bytes; logged "
-				"output can be truncated",
-				bufsize);
+			if (syslog_is_disabled()) {
+				fprintf(stderr, "vupslog: vsnprintf needed "
+					"more than %" PRIuSIZE " bytes; logged "
+					"output can be truncated",
+					bufsize);
+			} else {
+				syslog(LOG_WARNING, "vupslog: vsnprintf needed "
+					"more than %" PRIuSIZE " bytes; logged "
+					"output can be truncated",
+					bufsize);
+			}
 			break;
 		}
 	} while(1);
@@ -1378,6 +2804,7 @@ static void vupslog(int priority, const char *fmt, va_list va, int use_strerror)
 	 * so mark the starting point whenever we first try to log */
 	if (upslog_start.tv_sec == 0) {
 		struct timeval		now;
+
 		gettimeofday(&now, NULL);
 		upslog_start = now;
 	}
@@ -1415,7 +2842,13 @@ static void vupslog(int priority, const char *fmt, va_list va, int use_strerror)
 /* Return the default path for the directory containing configuration files */
 const char * confpath(void)
 {
-	const char *path = getenv("NUT_CONFPATH");
+	static const char *path = NULL;
+
+	/* Cached by earlier calls? */
+	if (path)
+		return path;
+
+	path = getenv("NUT_CONFPATH");
 
 #ifdef WIN32
 	if (path == NULL) {
@@ -1426,13 +2859,22 @@ const char * confpath(void)
 
 	/* We assume, here and elsewhere, that
 	 * at least CONFPATH is always defined */
-	return (path != NULL && *path != '\0') ? path : CONFPATH;
+	if (path == NULL || *path == '\0')
+		path = CONFPATH;
+
+	return path;
 }
 
 /* Return the default path for the directory containing state files */
 const char * dflt_statepath(void)
 {
-	const char *path = getenv("NUT_STATEPATH");
+	static const char *path = NULL;
+
+	/* Cached by earlier calls? */
+	if (path)
+		return path;
+
+	path = getenv("NUT_STATEPATH");
 
 #ifdef WIN32
 	if (path == NULL) {
@@ -1443,7 +2885,10 @@ const char * dflt_statepath(void)
 
 	/* We assume, here and elsewhere, that
 	 * at least STATEPATH is always defined */
-	return (path != NULL && *path != '\0') ? path : STATEPATH;
+	if (path == NULL || *path == '\0')
+		path = STATEPATH;
+
+	return path;
 }
 
 /* Return the alternate path for pid files, for processes running as non-root
@@ -1454,7 +2899,11 @@ const char * dflt_statepath(void)
  */
 const char * altpidpath(void)
 {
-	const char * path;
+	static const char *path = NULL;
+
+	/* Cached by earlier calls? */
+	if (path)
+		return path;
 
 	path = getenv("NUT_ALTPIDPATH");
 	if ( (path == NULL) || (*path == '\0') ) {
@@ -1472,11 +2921,43 @@ const char * altpidpath(void)
 		return path;
 
 #ifdef ALTPIDPATH
-	return ALTPIDPATH;
+	path = ALTPIDPATH;
 #else
 	/* With WIN32 in the loop, this may be more than a fallback to STATEPATH: */
-	return dflt_statepath();
+	path = dflt_statepath();
+#endif
+
+	return path;
+}
+
+/* Return the main path for pid files, for processes running as root, such
+ * as upsmon. Typically this is the built-in PIDPATH (from configure script)
+ * but certain use-cases such as the test suite can override it with the
+ * NUT_PIDPATH environment variable.
+ */
+const char * rootpidpath(void)
+{
+	static const char *path = NULL;
+
+	/* Cached by earlier calls? */
+	if (path)
+		return path;
+
+	path = getenv("NUT_PIDPATH");
+
+#ifdef WIN32
+	if (path == NULL) {
+		/* fall back to built-in pathname relative to binary/workdir */
+		path = getfullpath(PATH_ETC);
+	}
 #endif
+
+	/* We assume, here and elsewhere, that
+	 * at least PIDPATH is always defined */
+	if (path == NULL || *path == '\0')
+		path = PIDPATH;
+
+	return path;
 }
 
 /* Die with a standard message if socket filename is too long */
@@ -1587,8 +3068,13 @@ void s_upsdebug_with_errno(int level, const char *fmt, ...)
 			ret = snprintf(fmt2, sizeof(fmt2), "[D%d] %s", level, fmt);
 		}
 		if ((ret < 0) || (ret >= (int) sizeof(fmt2))) {
-			syslog(LOG_WARNING, "upsdebug_with_errno: snprintf needed more than %d bytes",
-				LARGEBUF);
+			if (syslog_is_disabled()) {
+				fprintf(stderr, "upsdebug_with_errno: snprintf needed more than %d bytes",
+					LARGEBUF);
+			} else {
+				syslog(LOG_WARNING, "upsdebug_with_errno: snprintf needed more than %d bytes",
+					LARGEBUF);
+			}
 		} else {
 			fmt = (const char *)fmt2;
 		}
@@ -1637,8 +3123,13 @@ void s_upsdebugx(int level, const char *fmt, ...)
 		}
 
 		if ((ret < 0) || (ret >= (int) sizeof(fmt2))) {
-			syslog(LOG_WARNING, "upsdebugx: snprintf needed more than %d bytes",
-				LARGEBUF);
+			if (syslog_is_disabled()) {
+				fprintf(stderr, "upsdebugx: snprintf needed more than %d bytes",
+					LARGEBUF);
+			} else {
+				syslog(LOG_WARNING, "upsdebugx: snprintf needed more than %d bytes",
+					LARGEBUF);
+			}
 		} else {
 			fmt = (const char *)fmt2;
 		}
@@ -1765,10 +3256,25 @@ void s_upsdebug_ascii(int level, const char *msg, const void *buf, size_t len)
 
 static void vfatal(const char *fmt, va_list va, int use_strerror)
 {
+	/* Normally we enable SYSLOG and disable STDERR,
+	 * unless NUT_DEBUG_SYSLOG envvar interferes as
+	 * interpreted in syslog_is_disabled() method: */
+	int	syslog_disabled = syslog_is_disabled(),
+		stderr_disabled = (syslog_disabled == 0 || syslog_disabled == 2);
+
 	if (xbit_test(upslog_flags, UPSLOG_STDERR_ON_FATAL))
 		xbit_set(&upslog_flags, UPSLOG_STDERR);
-	if (xbit_test(upslog_flags, UPSLOG_SYSLOG_ON_FATAL))
-		xbit_set(&upslog_flags, UPSLOG_SYSLOG);
+	if (xbit_test(upslog_flags, UPSLOG_SYSLOG_ON_FATAL)) {
+		if (syslog_disabled) {
+			/* FIXME: Corner case... env asked for stderr
+			 * instead of syslog - should we care about
+			 * UPSLOG_STDERR_ON_FATAL being not set? */
+			if (!stderr_disabled)
+				xbit_set(&upslog_flags, UPSLOG_STDERR);
+		} else {
+			xbit_set(&upslog_flags, UPSLOG_SYSLOG);
+		}
+	}
 
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_NONLITERAL
 #pragma GCC diagnostic push
@@ -2145,6 +3651,9 @@ void nut_prepare_search_paths(void) {
 				dupe = 1;
 #if HAVE_DECL_REALPATH
 				free((char *)dirname);
+				/* Have some valid value, for kicks (likely
+				 * to be ignored in the code path below) */
+				dirname = search_paths_builtin[i];
 #endif
 				break;
 			}
@@ -2155,10 +3664,17 @@ void nut_prepare_search_paths(void) {
 				"existing unique directory: %s",
 				__func__, count_filtered, dirname);
 #if !HAVE_DECL_REALPATH
+			/* Make a copy of table entry, else we have
+			 * a dynamic result of realpath() made above.
+			 */
 			dirname = (const char *)xstrdup(dirname);
 #endif
 			filtered_search_paths[count_filtered++] = dirname;
-		}
+		}	/* else: dirname was freed above (for realpath)
+			 * or is a reference to the table entry; no need
+			 * to free() it either way */
+
+		closedir(dp);
 	}
 
 	/* If we mangled this before, forget the old result: */
@@ -2248,27 +3764,36 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 	 */
 	DIR *dp;
 	struct dirent *dirp;
-	char *libname_path = NULL;
+	char *libname_path = NULL, *libname_alias = NULL;
 	char current_test_path[LARGEBUF];
 
+	upsdebugx(3, "%s('%s', %" PRIuSIZE ", '%s', %i): Entering method...",
+		__func__, base_libname, base_libname_length, dirname, index);
+
 	memset(current_test_path, 0, LARGEBUF);
 
 	if ((dp = opendir(dirname)) == NULL) {
 		if (index >= 0) {
-			upsdebugx(5,"NOT looking for lib %s in unreachable directory #%d : %s",
-				base_libname, index, dirname);
+			upsdebugx(5, "%s: NOT looking for lib %s in "
+				"unreachable directory #%d : %s",
+				__func__, base_libname, index, dirname);
 		} else {
-			upsdebugx(5,"NOT looking for lib %s in unreachable directory : %s",
-				base_libname, dirname);
+			upsdebugx(5, "%s: NOT looking for lib %s in "
+				"unreachable directory : %s",
+				__func__, base_libname, dirname);
 		}
 		return NULL;
 	}
 
 	if (index >= 0) {
-		upsdebugx(2,"Looking for lib %s in directory #%d : %s", base_libname, index, dirname);
+		upsdebugx(4, "%s: Looking for lib %s in directory #%d : %s",
+			__func__, base_libname, index, dirname);
 	} else {
-		upsdebugx(2,"Looking for lib %s in directory : %s", base_libname, dirname);
+		upsdebugx(4, "%s: Looking for lib %s in directory : %s",
+			__func__, base_libname, dirname);
 	}
+
+	/* TODO: Try a quick stat() first? */
 	while ((dirp = readdir(dp)) != NULL)
 	{
 #if !HAVE_DECL_REALPATH
@@ -2276,11 +3801,18 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 #endif
 		int compres;
 
-		upsdebugx(5,"Comparing lib %s with dirpath entry %s", base_libname, dirp->d_name);
+		upsdebugx(5, "%s: Comparing lib %s with dirpath entry %s",
+			__func__, base_libname, dirp->d_name);
 		compres = strncmp(dirp->d_name, base_libname, base_libname_length);
-		if (compres == 0
-		&&  dirp->d_name[base_libname_length] == '\0' /* avoid "*.dll.a" etc. */
-		) {
+		if (compres == 0) {
+			/* avoid "*.dll.a", ".so.1.2.3" etc. */
+			if (dirp->d_name[base_libname_length] != '\0') {
+				if (!libname_alias) {
+					libname_alias = xstrdup(dirp->d_name);
+				}
+				continue;
+			}
+
 			snprintf(current_test_path, LARGEBUF, "%s/%s", dirname, dirp->d_name);
 #if HAVE_DECL_REALPATH
 			libname_path = realpath(current_test_path, NULL);
@@ -2299,7 +3831,8 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 				for (p = current_test_path; *p != '\0' && (p - current_test_path) < LARGEBUF; p++) {
 					if (*p == '/') *p = '\\';
 				}
-				upsdebugx(3, "%s: WIN32: re-checking with %s", __func__, current_test_path);
+				upsdebugx(4, "%s: WIN32: re-checking with %s",
+					__func__, current_test_path);
 				if (stat(current_test_path, &st) == 0) {
 					if (st.st_size > 0) {
 						libname_path = xstrdup(current_test_path);
@@ -2312,7 +3845,8 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 				 * original dir, and no threading at this moment, to be safe!)
 				 * https://stackoverflow.com/a/66096983/4715872
 				 */
-				upsdebugx(3, "%s: WIN32: re-checking with %s", __func__, current_test_path + 2);
+				upsdebugx(4, "%s: WIN32: re-checking with %s",
+					__func__, current_test_path + 2);
 				if (stat(current_test_path + 2, &st) == 0) {
 					if (st.st_size > 0) {
 						libname_path = xstrdup(current_test_path + 2);
@@ -2322,9 +3856,9 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 # endif /* WIN32 */
 #endif  /* HAVE_DECL_REALPATH */
 
-			upsdebugx(2,"Candidate path for lib %s is %s (realpath %s)",
+			upsdebugx(2, "Candidate path for lib %s is %s (realpath %s)",
 				base_libname, current_test_path,
-				(libname_path!=NULL)?libname_path:"NULL");
+				NUT_STRARG(libname_path));
 			if (libname_path != NULL)
 				break;
 		}
@@ -2332,6 +3866,17 @@ static char * get_libname_in_dir(const char* base_libname, size_t base_libname_l
 
 	closedir(dp);
 
+	if (libname_alias) {
+		if (!libname_path) {
+			upsdebugx(1, "Got no strong candidate path for lib %s in %s"
+				", but saw seemingly related names (are you missing"
+				" a symbolic link, perhaps?) e.g.: %s",
+				base_libname, dirname, libname_alias);
+		}
+
+		free(libname_alias);
+	}
+
 	return libname_path;
 }
 
@@ -2345,11 +3890,18 @@ static char * get_libname_in_pathset(const char* base_libname, size_t base_libna
 	char *onedir = NULL;
 	char* pathset_tmp;
 
+	upsdebugx(3, "%s('%s', %" PRIuSIZE ", '%s', %i): Entering method...",
+		__func__, base_libname, base_libname_length,
+		NUT_STRARG(pathset),
+		counter ? *counter : -1);
+
 	if (!pathset || *pathset == '\0')
 		return NULL;
 
 	/* First call to tokenization passes the string, others pass NULL */
 	pathset_tmp = xstrdup(pathset);
+	upsdebugx(4, "%s: Looking for lib %s in a colon-separated path set",
+		__func__, base_libname);
 	while (NULL != (onedir = strtok( (onedir ? NULL : pathset_tmp), ":" ))) {
 		libname_path = get_libname_in_dir(base_libname, base_libname_length, onedir, (*counter)++);
 		if (libname_path != NULL)
@@ -2362,6 +3914,8 @@ static char * get_libname_in_pathset(const char* base_libname, size_t base_libna
 	pathset_tmp = xstrdup(pathset);
 	if (!libname_path) {
 		onedir = NULL; /* probably is NULL already, but better ensure this */
+		upsdebugx(4, "%s: WIN32: Looking for lib %s in a semicolon-separated path set",
+			__func__, base_libname);
 		while (NULL != (onedir = strtok( (onedir ? NULL : pathset_tmp), ";" ))) {
 			libname_path = get_libname_in_dir(base_libname, base_libname_length, onedir, (*counter)++);
 			if (libname_path != NULL)
@@ -2381,29 +3935,77 @@ char * get_libname(const char* base_libname)
 	int index = 0, counter = 0;
 	char *libname_path = NULL;
 	size_t base_libname_length = strlen(base_libname);
+	struct stat	st;
+
+	upsdebugx(3, "%s('%s'): Entering method...", __func__, base_libname);
+
+	/* First, check for an exact hit by absolute/relative path
+	 * if `base_libname` includes path separator character(s) */
+	if (xbasename(base_libname) != base_libname) {
+		upsdebugx(4, "%s: Looking for lib %s by exact hit...",
+			__func__, base_libname);
+#if HAVE_DECL_REALPATH
+		/* allocates the buffer we free() later */
+		libname_path = realpath(base_libname, NULL);
+		if (libname_path != NULL) {
+			if (stat(libname_path, &st) == 0) {
+				if (st.st_size > 0) {
+					upsdebugx(2, "Looking for lib %s, found by exact hit",
+						base_libname);
+					goto found;
+				}
+			}
+
+			/* else: does not actually exist */
+			free(libname_path);
+			libname_path = NULL;
+		}
+#endif	/* HAVE_DECL_REALPATH */
+
+		/* Just check if candidate name is (points to?) valid file */
+		if (stat(base_libname, &st) == 0) {
+			if (st.st_size > 0) {
+				libname_path = xstrdup(base_libname);
+				upsdebugx(2, "Looking for lib %s, found by exact hit",
+					base_libname);
+				goto found;
+			}
+		}
+	}
 
 	/* Normally these envvars should not be set, but if the user insists,
 	 * we should prefer the override... */
 #ifdef BUILD_64
+	upsdebugx(4, "%s: Looking for lib %s by path-set LD_LIBRARY_PATH_64...",
+		__func__, base_libname);
 	libname_path = get_libname_in_pathset(base_libname, base_libname_length, getenv("LD_LIBRARY_PATH_64"), &counter);
 	if (libname_path != NULL) {
-		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH_64", base_libname);
+		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH_64",
+			base_libname);
 		goto found;
 	}
 #else
+	upsdebugx(4, "%s: Looking for lib %s by path-set LD_LIBRARY_PATH_32...",
+		__func__, base_libname);
 	libname_path = get_libname_in_pathset(base_libname, base_libname_length, getenv("LD_LIBRARY_PATH_32"), &counter);
 	if (libname_path != NULL) {
-		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH_32", base_libname);
+		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH_32",
+			base_libname);
 		goto found;
 	}
 #endif
 
+	upsdebugx(4, "%s: Looking for lib %s by path-set LD_LIBRARY_PATH...",
+		__func__, base_libname);
 	libname_path = get_libname_in_pathset(base_libname, base_libname_length, getenv("LD_LIBRARY_PATH"), &counter);
 	if (libname_path != NULL) {
-		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH", base_libname);
+		upsdebugx(2, "Looking for lib %s, found in LD_LIBRARY_PATH",
+			base_libname);
 		goto found;
 	}
 
+	upsdebugx(4, "%s: Looking for lib %s by search_paths[]...",
+		__func__, base_libname);
 	for (index = 0 ; (search_paths[index] != NULL) && (libname_path == NULL) ; index++)
 	{
 		libname_path = get_libname_in_dir(base_libname, base_libname_length, search_paths[index], counter++);
@@ -2418,17 +4020,23 @@ char * get_libname(const char* base_libname)
 	if (!libname_path) {
 		/* First check near the EXE (if executing it from another
 		 * working directory) */
+		upsdebugx(4, "%s: WIN32: Looking for lib %s near EXE...",
+			__func__, base_libname);
 		libname_path = get_libname_in_dir(base_libname, base_libname_length, getfullpath(NULL), counter++);
 	}
 
 # ifdef PATH_LIB
 	if (!libname_path) {
+		upsdebugx(4, "%s: WIN32: Looking for lib %s via PATH_LIB...",
+			__func__, base_libname);
 		libname_path = get_libname_in_dir(base_libname, base_libname_length, getfullpath(PATH_LIB), counter++);
 	}
 # endif
 
 	if (!libname_path) {
 		/* Resolve "lib" dir near the one with current executable ("bin" or "sbin") */
+		upsdebugx(4, "%s: WIN32: Looking for lib %s in a 'lib' dir near EXE...",
+			__func__, base_libname);
 		libname_path = get_libname_in_dir(base_libname, base_libname_length, getfullpath("/../lib"), counter++);
 	}
 #endif  /* WIN32 so far */
@@ -2437,13 +4045,15 @@ char * get_libname(const char* base_libname)
 	/* Windows-specific: DLLs can be provided by common "PATH" envvar,
 	 * at lowest search priority though (after EXE dir, system, etc.) */
 	if (!libname_path) {
-		upsdebugx(2, "Looking for lib %s in PATH", base_libname);
+		upsdebugx(4, "%s: WIN32: Looking for lib %s in PATH",
+			__func__, base_libname);
 		libname_path = get_libname_in_pathset(base_libname, base_libname_length, getenv("PATH"), &counter);
 	}
 #endif  /* WIN32 */
 
 found:
-	upsdebugx(1,"Looking for lib %s, found %s", base_libname, (libname_path!=NULL)?libname_path:"NULL");
+	upsdebugx(1, "Looking for lib %s, found %s",
+		base_libname, NUT_STRARG(libname_path));
 	return libname_path;
 }
 
diff --git a/common/nutconf.cpp b/common/nutconf.cpp
index 33adb3c47c..35c4ffd5e6 100644
--- a/common/nutconf.cpp
+++ b/common/nutconf.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
         2012	Emilien Kia <emilien.kia@gmail.com>
+        2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -55,15 +56,30 @@ NutParser::~NutParser() {}
 template <typename T>
 Settable<T> StringToSettableNumber(const std::string & src)
 {
-	std::stringstream ss(src);
-	T result;
-	if(ss >> result)
-	{
-		return Settable<T>(result);
-	}
-	else
-	{
-		return Settable<T>();
+	if (typeid(T) == typeid(bool)) {
+		static const Settable<T> b0(false);
+		static const Settable<T> b1(true);
+
+		// See also: GenericConfiguration::str2bool()
+		// FIXME: Can these two methods be merged?
+		if ("true" == src) return b1;
+		if ("on"   == src) return b1;
+		if ("1"    == src) return b1;
+		if ("yes"  == src) return b1;
+		if ("ok"   == src) return b1;
+
+		return b0;
+	} else {
+		std::stringstream ss(src);
+		T result;
+		if(ss >> result)
+		{
+			return Settable<T>(result);
+		}
+		else
+		{
+			return Settable<T>();
+		}
 	}
 }
 
@@ -96,44 +112,53 @@ void NutParser::setOptions(unsigned int options, bool set)
 	}
 }
 
-char NutParser::get() {
+char NutParser::get()
+{
 	if (_pos >= _buffer.size())
 		return 0;
 	else
 		return _buffer[_pos++];
 }
 
-char NutParser::peek() {
+char NutParser::peek()
+{
 	return _buffer[_pos];
 }
 
-size_t NutParser::getPos()const {
+size_t NutParser::getPos()const
+{
 	return _pos;
 }
 
-void NutParser::setPos(size_t pos) {
+void NutParser::setPos(size_t pos)
+{
 	_pos = pos;
 }
 
-char NutParser::charAt(size_t pos)const {
+char NutParser::charAt(size_t pos)const
+{
 	return _buffer[pos];
 }
 
-void NutParser::pushPos() {
+void NutParser::pushPos()
+{
 	_stack.push_back(_pos);
 }
 
-size_t NutParser::popPos() {
+size_t NutParser::popPos()
+{
 	size_t pos = _stack.back();
 	_stack.pop_back();
 	return pos;
 }
 
-void NutParser::rewind() {
+void NutParser::rewind()
+{
 	_pos = popPos();
 }
 
-void NutParser::back() {
+void NutParser::back()
+{
 	if (_pos > 0)
 		--_pos;
 }
@@ -144,7 +169,8 @@ void NutParser::back() {
  *             | '\\' ( __SPACES__ | '\\' | '\"' | '#' )
  * TODO: accept "\t", "\s", "\r", "\n" ??
  */
-std::string NutParser::parseCHARS() {
+std::string NutParser::parseCHARS()
+{
 	bool escaped = false; // Is char escaped ?
 	std::string res; // Stored string
 
@@ -180,7 +206,8 @@ std::string NutParser::parseCHARS() {
  *             | '\\' ( '\\' | '\"' )
  * TODO: accept "\t", "\s", "\r", "\n" ??
  */
-std::string NutParser::parseSTRCHARS() {
+std::string NutParser::parseSTRCHARS()
+{
 	bool escaped = false; // Is char escaped ?
 	std::string str; // Stored string
 
@@ -213,7 +240,8 @@ std::string NutParser::parseSTRCHARS() {
 /** Parse a string source for getting the next token, ignoring spaces.
  * \return Token type.
  */
-NutParser::Token NutParser::parseToken() {
+NutParser::Token NutParser::parseToken()
+{
 
 	/** Lexical parsing machine state enumeration.*/
 	typedef enum {
@@ -387,7 +415,8 @@ NutParser::Token NutParser::parseToken() {
 	return token;
 }
 
-std::list<NutParser::Token> NutParser::parseLine() {
+std::list<NutParser::Token> NutParser::parseLine()
+{
 	std::list<NutParser::Token> res;
 
 	while (true) {
@@ -410,6 +439,30 @@ std::list<NutParser::Token> NutParser::parseLine() {
 			case Token::TOKEN_NONE:
 			case Token::TOKEN_EOL:
 				return res;
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+			default:
+				/* Must not occur. */
+				break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 		}
 	}
 }
@@ -419,19 +472,23 @@ std::list<NutParser::Token> NutParser::parseLine() {
 //
 
 NutConfigParser::NutConfigParser(const char* buffer, unsigned int options) :
-NutParser(buffer, options) {
+NutParser(buffer, options)
+{
 }
 
 NutConfigParser::NutConfigParser(const std::string& buffer, unsigned int options) :
-NutParser(buffer, options) {
+NutParser(buffer, options)
+{
 }
 
-void NutConfigParser::parseConfig(BaseConfiguration* config) {
+void NutConfigParser::parseConfig(BaseConfiguration* config)
+{
 	NUT_UNUSED_VARIABLE(config);
 	parseConfig();
 }
 
-void NutConfigParser::parseConfig() {
+void NutConfigParser::parseConfig()
+{
 	onParseBegin();
 
 	enum ConfigParserState {
@@ -670,6 +727,9 @@ void NutConfigParser::parseConfig() {
 						break;
 				}
 				break;
+
+			default:
+				break;
 		}
 	}
 
@@ -695,6 +755,8 @@ void NutConfigParser::parseConfig() {
 		case CPS_DEFAULT:
 			/* TOTHINK: no-op? */
 			break;
+		default:
+			break;
 	}
 #ifdef __clang__
 #pragma clang diagnostic pop
@@ -713,23 +775,31 @@ void NutConfigParser::parseConfig() {
 //
 
 DefaultConfigParser::DefaultConfigParser(const char* buffer) :
-NutConfigParser(buffer) {
+NutConfigParser(buffer)
+{
 }
 
 DefaultConfigParser::DefaultConfigParser(const std::string& buffer) :
-NutConfigParser(buffer) {
+NutConfigParser(buffer)
+{
 }
 
-void DefaultConfigParser::onParseBegin() {
+void DefaultConfigParser::onParseBegin()
+{
 	// Start with empty section (i.e. global one)
 	_section.clear();
 }
 
-void DefaultConfigParser::onParseComment(const std::string& /*comment*/) {
+void DefaultConfigParser::onParseComment(
+		const std::string& /*comment*/)
+{
 	// Comments are ignored for now
 }
 
-void DefaultConfigParser::onParseSectionName(const std::string& sectionName, const std::string& /*comment*/) {
+void DefaultConfigParser::onParseSectionName(
+		const std::string& sectionName,
+		const std::string& /*comment*/)
+{
 	// Comments are ignored for now
 
 	// Process current section.
@@ -742,7 +812,12 @@ void DefaultConfigParser::onParseSectionName(const std::string& sectionName, con
 	_section.name = sectionName;
 }
 
-void DefaultConfigParser::onParseDirective(const std::string& directiveName, char /*sep*/, const ConfigParamList& values, const std::string& /*comment*/) {
+void DefaultConfigParser::onParseDirective(
+		const std::string& directiveName,
+		char /*sep*/,
+		const ConfigParamList& values,
+		const std::string& /*comment*/)
+{
 	// Comments are ignored for now
 	// Separator has no specific semantic in this context
 
@@ -753,7 +828,8 @@ void DefaultConfigParser::onParseDirective(const std::string& directiveName, cha
 	// TODO Can probably be optimized.
 }
 
-void DefaultConfigParser::onParseEnd() {
+void DefaultConfigParser::onParseEnd()
+{
 	// Process current (last) section
 	if (!_section.empty()) {
 		onParseSection(_section);
@@ -766,11 +842,13 @@ void DefaultConfigParser::onParseEnd() {
 // GenericConfigSection
 //
 
-bool GenericConfigSection::empty()const {
+bool GenericConfigSection::empty()const
+{
 	return name.empty() && entries.empty();
 }
 
-void GenericConfigSection::clear() {
+void GenericConfigSection::clear()
+{
 	name.clear();
 	entries.clear();
 }
@@ -976,7 +1054,135 @@ void GenericConfiguration::setStr(
 }
 
 
-long long int GenericConfiguration::getInt(const std::string & section, const std::string & entry, long long int val) const
+bool GenericConfiguration::getBool(
+		const std::string & section,
+		const std::string & entry,
+		bool                val) const
+{
+		std::string s = getStr(section, entry);
+		if (s.empty())
+			return val;
+		return str2bool(s);
+}
+
+
+bool GenericConfiguration::getFlag(
+		const std::string & section,
+		const std::string & entry) const
+{
+	ConfigParamList params;
+
+	if (!get(section, entry, params))
+		return false;
+
+	// Flag - if exists then "true"
+	return true;
+}
+
+
+void GenericConfiguration::setFlag(
+		const std::string & section,
+		const std::string & entry,
+		bool                val)
+{
+	ConfigParamList param;
+
+	if (val) {
+		param.push_back("true");
+		set(section, entry, param);
+	} else {
+		remove(section, entry);
+	}
+}
+
+
+long long int GenericConfiguration::getInt(
+		const std::string & section,
+		const std::string & entry,
+		long long int val) const
+{
+	ConfigParamList params;
+
+	if (!get(section, entry, params))
+		return val;
+
+	if (params.empty())
+		return val;
+
+	// TBD: What if there are multiple values?
+	std::stringstream val_str(params.front());
+
+	val_str >> val;
+
+	return val;
+}
+
+
+void GenericConfiguration::setInt(
+		const std::string & section,
+		const std::string & entry,
+		long long int val)
+{
+	std::stringstream val_str;
+	val_str << val;
+
+	set(section, entry, ConfigParamList(1, val_str.str()));
+}
+
+
+long long int GenericConfiguration::getIntHex(
+		const std::string & section,
+		const std::string & entry,
+		long long int val) const
+{
+	ConfigParamList params;
+
+	if (!get(section, entry, params))
+		return val;
+
+	if (params.empty())
+		return val;
+
+	// TBD: What if there are multiple values?
+	std::string s = params.front();
+	size_t foundPos = s.rfind("0x", 0);
+	if (foundPos == std::string::npos || foundPos != 0) {
+		// Add the prefix for hex conversion
+		s = "0x" + s;
+	}
+	std::stringstream val_str;
+	val_str << std::hex << s;
+
+	// Output into int type
+	val_str >> std::hex >> val;
+
+	return val;
+}
+
+
+void GenericConfiguration::setIntHex(
+		const std::string & section,
+		const std::string & entry,
+		long long int val)
+{
+	std::stringstream val_str;
+
+	// Note NUT v2.8.1 introduced these as "hexnum" values,
+	// but the strtoul() underneath knows to strip "0x" for
+	// base16 conversions - so can we write them either way:
+
+	// https://stackoverflow.com/a/61060765/4715872
+	// << std::showbase for "0x" in saved printouts
+	val_str << std::nouppercase << std::hex << val;
+
+	set(section, entry, ConfigParamList(1, val_str.str()));
+}
+
+
+double GenericConfiguration::getDouble(
+		const std::string & section,
+		const std::string & entry,
+		double val) const
 {
 	ConfigParamList params;
 
@@ -995,7 +1201,10 @@ long long int GenericConfiguration::getInt(const std::string & section, const st
 }
 
 
-void GenericConfiguration::setInt(const std::string & section, const std::string & entry, long long int val)
+void GenericConfiguration::setDouble(
+		const std::string & section,
+		const std::string & entry,
+		double val)
 {
 	std::stringstream val_str;
 	val_str << val;
@@ -1004,11 +1213,31 @@ void GenericConfiguration::setInt(const std::string & section, const std::string
 }
 
 
+nut::BoolInt GenericConfiguration::getBoolInt(
+		const std::string & section,
+		const std::string & entry,
+		nut::BoolInt val) const
+{
+	ConfigParamList params;
+
+	if (!get(section, entry, params))
+		return val;
+
+	if (params.empty())
+		return val;
+
+	// TBD: What if there are multiple values?
+	nut::BoolInt bi(params.front());
+
+	return bi;
+}
+
+
 bool GenericConfiguration::str2bool(const std::string & str)
 {
 	if ("true" == str) return true;
 	if ("on"   == str) return true;
-	if ("1"	== str) return true;
+	if ("1"    == str) return true;
 	if ("yes"  == str) return true;
 	if ("ok"   == str) return true;
 
@@ -1075,6 +1304,22 @@ UpsmonConfiguration::NotifyType UpsmonConfiguration::NotifyTypeFromString(const
 		return NOTIFY_NOCOMM;
 	else if(str=="NOPARENT")
 		return NOTIFY_NOPARENT;
+	else if(str=="CAL")
+		return NOTIFY_CAL;
+	else if(str=="NOTCAL")
+		return NOTIFY_NOTCAL;
+	else if(str=="OFF")
+		return NOTIFY_OFF;
+	else if(str=="NOTOFF")
+		return NOTIFY_NOTOFF;
+	else if(str=="BYPASS")
+		return NOTIFY_BYPASS;
+	else if(str=="NOTBYPASS")
+		return NOTIFY_NOTBYPASS;
+	else if(str=="SUSPEND_STARTING")
+		return NOTIFY_SUSPEND_STARTING;
+	else if(str=="SUSPEND_FINISHED")
+		return NOTIFY_SUSPEND_FINISHED;
 	else
 		return NOTIFY_TYPE_MAX;
 }
@@ -1150,7 +1395,16 @@ void UpsmonConfigParser::onParseDirective(const std::string& directiveName, char
 
 	if(_config)
 	{
-		if(directiveName == "RUN_AS_USER")
+		if(!(::strcasecmp(directiveName.c_str(), "DEBUG_MIN")))
+		{
+			// NOTE: We allow DEBUG_MIN in any casing as it can be copy-pasted
+			// between different configs and they use different historic casing
+			if(values.size()>0)
+			{
+				_config->debugMin = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else if(directiveName == "RUN_AS_USER")
 		{
 			if(values.size()>0)
 			{
@@ -1177,7 +1431,7 @@ void UpsmonConfigParser::onParseDirective(const std::string& directiveName, char
 				monitor.powerValue = StringToSettableNumber<unsigned int>(*it++);
 				monitor.username = *it++;
 				monitor.password = *it++;
-				monitor.isMaster = (*it) == "master";
+				monitor.isPrimary = (*it) == "primary";	// master for NUT v2.7.4 and older
 				_config->monitors.push_back(monitor);
 			}
 		}
@@ -1206,21 +1460,98 @@ void UpsmonConfigParser::onParseDirective(const std::string& directiveName, char
 		{
 			if(values.size()>0)
 			{
-				_config->poolFreq = StringToSettableNumber<unsigned int>(values.front());
+				_config->pollFreq = StringToSettableNumber<unsigned int>(values.front());
 			}
 		}
 		else if(directiveName == "POLLFREQALERT")
 		{
 			if(values.size()>0)
 			{
-				_config->poolFreqAlert = StringToSettableNumber<unsigned int>(values.front());
+				_config->pollFreqAlert = StringToSettableNumber<unsigned int>(values.front());
+			}
+		}
+		else if(directiveName == "POLLFAIL_LOG_THROTTLE_MAX")
+		{
+			if(values.size()>0)
+			{
+				_config->pollFailLogThrottleMax = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else if(directiveName == "OFFDURATION")
+		{
+			if(values.size()>0)
+			{
+				_config->offDuration = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else if(directiveName == "OBLBDURATION")
+		{
+			if(values.size()>0)
+			{
+				_config->oblbDuration = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else if(directiveName == "SHUTDOWNEXIT")
+		{
+			if(values.size()>0)
+			{
+				nut::BoolInt bi;
+				bi << values.front();
+				_config->shutdownExit = bi;
+			}
+		}
+		else if(directiveName == "CERTPATH")
+		{
+			if(values.size()>0)
+			{
+				_config->certPath = values.front();
+			}
+		}
+		else if(directiveName == "CERTIDENT")
+		{
+			if(values.size()==2)
+			{
+				_config->certIdent.certName = values.front();
+				_config->certIdent.certDbPass = (*(++values.begin()));
+			}
+		}
+		else if(directiveName == "CERTHOST")
+		{
+			if(values.size()==4)
+			{
+				nut::CertHost certHost;
+				ConfigParamList::const_iterator it = values.begin();
+				certHost.host       = *it++;
+				certHost.certName   = *it++;
+				certHost.certVerify = *it++;
+				certHost.forceSsl   = *it++;
+
+				_config->certHosts.push_back(certHost);
+			}
+		}
+		else if(directiveName == "CERTVERIFY")
+		{
+			if(values.size()>0)
+			{
+				nut::BoolInt bi;
+				bi << values.front();
+				_config->certVerify = bi;
+			}
+		}
+		else if(directiveName == "FORCESSL")
+		{
+			if(values.size()>0)
+			{
+				nut::BoolInt bi;
+				bi << values.front();
+				_config->forceSsl = bi;
 			}
 		}
 		else if(directiveName == "HOSTSYNC")
 		{
 			if(values.size()>0)
 			{
-				_config->hotSync = StringToSettableNumber<unsigned int>(values.front());
+				_config->hostSync = StringToSettableNumber<unsigned int>(values.front());
 			}
 		}
 		else if(directiveName == "DEADTIME")
@@ -1400,16 +1731,70 @@ void NutConfConfigParser::onParseDirective(const std::string& directiveName, cha
 {
 	// Comments are ignored for now
 	// NOTE: although sep must be '=', sep is not verified.
-	if(_config && directiveName=="MODE" && values.size()==1)
-	{
-		std::string val = values.front();
-		NutConfiguration::NutMode mode = NutConfiguration::NutModeFromString(val);
-		if(mode != NutConfiguration::MODE_UNKNOWN)
-			_config->mode = mode;
-	}
-	else
+	if(_config)
 	{
-		// TODO WTF with errors ?
+		if(directiveName == "MODE")
+		{
+			if (values.size()==1) {
+				std::string val = values.front();
+				NutConfiguration::NutMode mode = NutConfiguration::NutModeFromString(val);
+				if(mode != NutConfiguration::MODE_UNKNOWN)
+					_config->mode = mode;
+			}
+		}
+		else if(directiveName == "ALLOW_NO_DEVICE")
+		{
+			if(values.size()>0)
+			{
+				_config->allowNoDevice = StringToSettableNumber<bool>(values.front());
+			}
+		}
+		else if(directiveName == "ALLOW_NOT_ALL_LISTENERS")
+		{
+			if(values.size()>0)
+			{
+				_config->allowNotAllListeners = StringToSettableNumber<bool>(values.front());
+			}
+		}
+		else if(directiveName == "UPSD_OPTIONS")
+		{
+			if(values.size()>0)
+			{
+				_config->upsdOptions = values.front();
+			}
+		}
+		else if(directiveName == "UPSMON_OPTIONS")
+		{
+			if(values.size()>0)
+			{
+				_config->upsmonOptions = values.front();
+			}
+		}
+		else if(directiveName == "POWEROFF_WAIT")
+		{
+			if(values.size()>0)
+			{
+				_config->poweroffWait = StringToSettableNumber<unsigned int>(values.front());
+			}
+		}
+		else if(directiveName == "POWEROFF_QUIET")
+		{
+			if(values.size()>0)
+			{
+				_config->poweroffQuiet = StringToSettableNumber<bool>(values.front());
+			}
+		}
+		else if(directiveName == "NUT_DEBUG_LEVEL")
+		{
+			if(values.size()>0)
+			{
+				_config->debugLevel = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else
+		{
+			// TODO WTF with errors ?
+		}
 	}
 }
 
@@ -1508,7 +1893,16 @@ void UpsdConfigParser::onParseDirective(const std::string& directiveName, char s
 
 	if(_config)
 	{
-		if(directiveName == "MAXAGE")
+		if(!(::strcasecmp(directiveName.c_str(), "DEBUG_MIN")))
+		{
+			// NOTE: We allow DEBUG_MIN in any casing as it can be copy-pasted
+			// between different configs and they use different historic casing
+			if(values.size()>0)
+			{
+				_config->debugMin = StringToSettableNumber<int>(values.front());
+			}
+		}
+		else if(directiveName == "MAXAGE")
 		{
 			if(values.size()>0)
 			{
@@ -1529,6 +1923,34 @@ void UpsdConfigParser::onParseDirective(const std::string& directiveName, char s
 				_config->maxConn = StringToSettableNumber<unsigned int>(values.front());
 			}
 		}
+		else if(directiveName == "TRACKINGDELAY")
+		{
+			if(values.size()>0)
+			{
+				_config->trackingDelay = StringToSettableNumber<unsigned int>(values.front());
+			}
+		}
+		else if(directiveName == "ALLOW_NO_DEVICE")
+		{
+			if(values.size()>0)
+			{
+				_config->allowNoDevice = StringToSettableNumber<bool>(values.front());
+			}
+		}
+		else if(directiveName == "ALLOW_NOT_ALL_LISTENERS")
+		{
+			if(values.size()>0)
+			{
+				_config->allowNotAllListeners = StringToSettableNumber<bool>(values.front());
+			}
+		}
+		else if(directiveName == "DISABLE_WEAK_SSL")
+		{
+			if(values.size()>0)
+			{
+				_config->allowNotAllListeners = StringToSettableNumber<bool>(values.front());
+			}
+		}
 		else if(directiveName == "CERTFILE")
 		{
 			if(values.size()>0)
@@ -1536,6 +1958,28 @@ void UpsdConfigParser::onParseDirective(const std::string& directiveName, char s
 				_config->certFile = values.front();
 			}
 		}
+		else if(directiveName == "CERTPATH")
+		{
+			if(values.size()>0)
+			{
+				_config->certPath = values.front();
+			}
+		}
+		else if(directiveName == "CERTIDENT")
+		{
+			if(values.size()==2)
+			{
+				_config->certIdent.certName = values.front();
+				_config->certIdent.certDbPass = (*(++values.begin()));
+			}
+		}
+		else if(directiveName == "CERTREQUEST")
+		{
+			if(values.size()>0)
+			{
+				_config->certRequestLevel = StringToSettableNumber<unsigned int>(values.front());
+			}
+		}
 		else if(directiveName == "LISTEN")
 		{
 			if(values.size()==1 || values.size()==2)
@@ -1570,11 +2014,11 @@ UpsdUsersConfiguration::upsmon_mode_t UpsdUsersConfiguration::getUpsmonMode() co
 {
 	std::string mode_str = getStr("upsmon", "upsmon");
 
-	if ("master" == mode_str)
-		return UPSMON_MASTER;
+	if ("primary" == mode_str || "master" == mode_str)
+		return UPSMON_PRIMARY;
 
-	if ("slave" == mode_str)
-		return UPSMON_SLAVE;
+	if ("secondary" == mode_str || "slave" == mode_str)
+		return UPSMON_SECONDARY;
 
 	return UPSMON_UNDEF;
 }
@@ -1584,7 +2028,8 @@ void UpsdUsersConfiguration::setUpsmonMode(upsmon_mode_t mode)
 {
 	assert(UPSMON_UNDEF != mode);
 
-	setStr("upsmon", "upsmon", (UPSMON_MASTER == mode ? "master" : "slave"));
+	setStr("upsmon", "upsmon", (UPSMON_PRIMARY == mode ? "primary" : "secondary"));
+	/* NUT v2.7.4 and older: setStr("upsmon", "upsmon", (UPSMON_PRIMARY == mode ? "master" : "slave")); */
 }
 
 
diff --git a/common/nutipc.cpp b/common/nutipc.cpp
index eaa2829f8e..d8bf131271 100644
--- a/common/nutipc.cpp
+++ b/common/nutipc.cpp
@@ -5,6 +5,10 @@
 
         Author: Vaclav Krpec  <VaclavKrpec@Eaton.com>
 
+    Copyright (C) 2024 NUT Community
+
+        Author: Jim Klimov  <jimklimov+nut@gmail.com>
+
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
@@ -35,6 +39,7 @@
 # define HAVE_LOCALTIME_R 111
 #endif
 
+#include "common.h"
 #include "nutipc.hpp"
 #include "nutstream.hpp"
 
@@ -293,8 +298,9 @@ int Signal::send(Signal::enum_t signame, const std::string & pid_file) {
 int NutSignal::send(NutSignal::enum_t signame, const std::string & process) {
 	std::string pid_file;
 
-	// TBD: What's ALTPIDPATH and shouldn't we also consider it?
-	pid_file += PIDPATH;
+	// FIXME: What about ALTPIDPATH (for non-root daemons)
+	// and shouldn't we also consider it (e.g. try/catch)?
+	pid_file += rootpidpath();
 	pid_file += '/';
 	pid_file += process;
 	pid_file += ".pid";
diff --git a/common/nutstream.cpp b/common/nutstream.cpp
index 555cc44f15..4a0092d2f1 100644
--- a/common/nutstream.cpp
+++ b/common/nutstream.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
         2012	Vaclav Krpec  <VaclavKrpec@Eaton.com>
+        2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -299,7 +300,23 @@ static const char* getTmpDirPath() {
 	return "/tmp";
 }
 
+/* Pedantic builds complain about the static variable below...
+ * It is assumed safe to ignore since it is a std::string with
+ * no complex teardown at program exit.
+ */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
+#pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
+#  pragma GCC diagnostic ignored "-Wglobal-constructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
+#  pragma GCC diagnostic ignored "-Wexit-time-destructors"
+# endif
+#endif
 const std::string NutFile::m_tmp_dir(getTmpDirPath());
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
+#pragma GCC diagnostic pop
+#endif
 
 NutFile::NutFile(anonymous_t):
 	m_name(""),
@@ -415,6 +432,31 @@ const char * NutFile::strAccessMode(access_t mode)
 		case APPEND_ONLY:
 			mode_str = append_only;
 			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
 	assert(nullptr != mode_str);
@@ -1032,6 +1074,8 @@ bool NutSocket::accept(
 		case ENFILE:		// Open file descriptors per-system limit was reached
 		case EPROTO:		// Protocol error
 			return false;
+		default:
+			break;
 	}
 
 	std::stringstream e;
diff --git a/common/nutwriter.cpp b/common/nutwriter.cpp
index 8cc232bcdc..b3db8d69a6 100644
--- a/common/nutwriter.cpp
+++ b/common/nutwriter.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
         2012	Vaclav Krpec  <VaclavKrpec@Eaton.com>
+        2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -29,7 +30,7 @@
 #include <list>
 #include <map>
 #include <cassert>
-
+#include <typeinfo>
 
 /**
  *  \brief  NUT configuration directive generator
@@ -64,6 +65,50 @@
 	} while (0)
 
 
+/**
+ *  \brief  Shell (envvar) configuration directive generator
+ *
+ *  The macro is used to simplify generation of
+ *  nut.conf file directives.
+ *
+ *  IMPORTANT NOTE:
+ *  In case of writing error, the macro causes immediate
+ *  return from the calling function (propagating the writing status).
+ *
+ *  \param  name       Directive name
+ *  \param  arg_t      Directive argument implementation type
+ *  \param  arg        Directive argument
+ *  \param  quote_arg  Boolean flag; check to quote the argument
+ */
+// NOTE: Due to this being a macro applied to any argument type,
+// implementation for e.g. bool handling jumps through hoops like
+// stringification and back. FIXME: working optimization welcome.
+#define SHELL_CONFIG_DIRECTIVEX(name, arg_t, arg, quote_arg) \
+	do { \
+		if ((arg).set()) { \
+			const arg_t & arg_val = (arg); \
+			std::stringstream ss; \
+			ss << name << '='; \
+			if (quote_arg) \
+				ss << '\''; \
+			if (typeid(arg_val) == typeid(bool&)) { \
+				std::stringstream ssb; \
+				ssb << arg_val; \
+				std::string sb = ssb.str(); \
+				if ("1" == sb) { ss << "true"; } \
+				else if ("0" == sb) { ss << "false"; } \
+				else { ss << arg_val; } \
+			} else \
+				ss << arg_val; \
+			if (quote_arg) \
+				ss << '\''; \
+			status_t status = writeDirective(ss.str()); \
+			if (NUTW_OK != status) \
+				return status; \
+		} \
+	} while (0)
+
+
 namespace nut {
 
 
@@ -71,10 +116,18 @@ namespace nut {
  * error: 'ClassName' has no out-of-line virtual method definitions; its vtable
  *   will be emitted in every translation unit [-Werror,-Wweak-vtables]
  */
-NutConfigWriter::~NutConfigWriter() {}
-NutConfConfigWriter::~NutConfConfigWriter() {}
-UpsmonConfigWriter::~UpsmonConfigWriter() {}
-UpsdConfigWriter::~UpsdConfigWriter() {}
+NutConfigWriter::~NutConfigWriter() {}	// generic interface/base class
+// Flat-config classes:
+NutConfConfigWriter::~NutConfConfigWriter() {}	// nut.conf, shell format
+UpsmonConfigWriter::~UpsmonConfigWriter() {}	// upsmon.conf
+UpsdConfigWriter::~UpsdConfigWriter() {}		// upsd.conf
+// Structured-config classes R/W is handled via GenericConfiguration:
+//	UpsConfiguration:		ups.conf
+//	UpsdUsersConfiguration:	upsd.users
+// Not handled currently:
+//	xxx:	upssched.conf
+//	xxx:	upsset.conf
+//	xxx:	hosts.conf
 
 // End-of-Line separators (arch. dependent)
 
@@ -97,6 +150,62 @@ const std::string GenericConfigWriter::s_default_section_entry_indent("\t");
 const std::string GenericConfigWriter::s_default_section_entry_separator(" = ");
 
 
+/**
+ *  \brief  NSS certificate identity serializer
+ *
+ *  \param  ident  Certificate identity object
+ *
+ *  \return Serialized certificate identity
+ */
+static std::string serializeCertIdent(const nut::CertIdent & ident) {
+	std::stringstream directive;
+	const std::string & val1 = (ident.certName), val2 = (ident.certDbPass);
+
+	directive << "CERTIDENT \"" << val1 << "\" \"" << val2 << "\"";
+
+	return directive.str();
+}
+
+
+/**
+ *  \brief  NSS certificate-protected host info serializer
+ *
+ *  \param  certHost  Certificate-protected host info object
+ *
+ *  \return Serialized certificate-protected host info
+ */
+static std::string serializeCertHost(const nut::CertHost & certHost) {
+	std::stringstream directive;
+	const std::string & val1 = (certHost.host), val2 = (certHost.certName);
+
+	directive << "CERTHOST \"" << val1 << "\" \"" << val2 << "\"";
+
+	// Spec says to write these as 0/1 integers
+	nut::BoolInt bi;
+	int i;
+	// NOTE: After copy-assignments below (which inherit original strictness),
+	// need to add relaxed mode for 0/1 as false/true handling:
+	//bi.bool01 = true;
+
+	// Avoid static analysis concerns that the internal _value
+	// "may be used uninitialized in this function" (ETOOSMART):
+	bi = false;
+
+	// Assumed to be set() - exception otherwise
+	bi = certHost.certVerify;
+	bi.bool01 = true;
+	i = bi;
+	directive << " " << i;
+
+	bi = certHost.forceSsl;
+	bi.bool01 = true;
+	i = bi;
+	directive << " " << i;
+
+	return directive.str();
+}
+
+
 NutWriter::status_t NutWriter::writeEachLine(const std::string & str, const std::string & pref) {
 	for (size_t pos = 0; pos < str.size(); ) {
 		// Prefix every line
@@ -145,11 +254,10 @@ NutWriter::status_t SectionlessConfigWriter::writeSectionName(const std::string
 
 
 NutWriter::status_t NutConfConfigWriter::writeConfig(const NutConfiguration & config) {
-	status_t status;
-
 	// Mode
 	// TBD: How should I serialize an unknown mode?
 	if (config.mode.set()) {
+		status_t status;
 		std::string mode_str;
 
 		NutConfiguration::NutMode mode = config.mode;
@@ -181,6 +289,31 @@ NutWriter::status_t NutConfConfigWriter::writeConfig(const NutConfiguration & co
 			case NutConfiguration::MODE_MANUAL:
 				mode_str = "manual";
 				break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+			default:
+				/* Must not occur. */
+				break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 		}
 
 		status = writeDirective("MODE=" + mode_str);
@@ -189,6 +322,31 @@ NutWriter::status_t NutConfConfigWriter::writeConfig(const NutConfiguration & co
 			return status;
 	}
 
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE)
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+	SHELL_CONFIG_DIRECTIVEX("ALLOW_NO_DEVICE",		bool,			config.allowNoDevice,	false);
+	SHELL_CONFIG_DIRECTIVEX("ALLOW_NOT_ALL_LISTENERS",	bool,		config.allowNotAllListeners,	false);
+	SHELL_CONFIG_DIRECTIVEX("UPSD_OPTIONS",			std::string,	config.upsdOptions,		true);
+	SHELL_CONFIG_DIRECTIVEX("UPSMON_OPTIONS",		std::string,	config.upsmonOptions,	true);
+	SHELL_CONFIG_DIRECTIVEX("POWEROFF_WAIT",		unsigned int,	config.poweroffWait,	false);
+	SHELL_CONFIG_DIRECTIVEX("POWEROFF_QUIET",		bool,			config.poweroffQuiet,	false);
+	SHELL_CONFIG_DIRECTIVEX("NUT_DEBUG_LEVEL",		int,			config.debugLevel,		false);
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE)
+# pragma GCC diagnostic pop
+#endif
+
 	return NUTW_OK;
 }
 
@@ -240,6 +398,14 @@ const NotifyFlagsStrings::TypeStrings NotifyFlagsStrings::type_str = {
 	"REPLBATT",	// NOTIFY_REPLBATT
 	"NOCOMM",	// NOTIFY_NOCOMM
 	"NOPARENT",	// NOTIFY_NOPARENT
+	"CAL\t",	// NOTIFY_CAL (including padding)
+	"NOTCAL",	// NOTIFY_NOTCAL
+	"OFF\t",	// NOTIFY_OFF (including padding)
+	"NOTOFF",	// NOTIFY_NOTOFF
+	"BYPASS",	// NOTIFY_BYPASS
+	"NOTBYPASS",	// NOTIFY_NOTBYPASS
+	"SUSPEND_STARTING",	// NOTIFY_SUSPEND_STARTING
+	"SUSPEND_FINISHED",	// NOTIFY_SUSPEND_FINISHED
 };
 
 
@@ -391,8 +557,9 @@ static std::string serializeMonitor(const UpsmonConfiguration::Monitor & monitor
 	// Username & password
 	directive << monitor.username << ' ' << monitor.password << ' ';
 
-	// Master/slave
-	directive << (monitor.isMaster ? "master" : "slave");
+	// Primary/secondary (legacy master/slave)
+	directive << (monitor.isPrimary ? "primary" : "secondary");
+	/* NUT v2.7.4 and older: directive << (monitor.isPrimary ? "master" : "slave");*/
 
 	return directive.str();
 }
@@ -415,7 +582,7 @@ NutWriter::status_t UpsmonConfigWriter::writeConfig(const UpsmonConfiguration &
 	 *  \param  arg        Directive argument
 	 *  \param  quote_arg  Boolean flag; check to quote the argument
 	 */
-	#define UPSMON_DIRECTIVEX(name, arg_t, arg, quote_arg) \
+#	define UPSMON_DIRECTIVEX(name, arg_t, arg, quote_arg) \
 		CONFIG_DIRECTIVEX(name, arg_t, arg, quote_arg)
 
 /* The "false" arg in macro below evaluates to `if (false) ...` after
@@ -431,14 +598,55 @@ NutWriter::status_t UpsmonConfigWriter::writeConfig(const UpsmonConfiguration &
 # pragma clang diagnostic push
 # pragma clang diagnostic ignored "-Wunreachable-code"
 #endif
-	UPSMON_DIRECTIVEX("RUN_AS_USER",    std::string,  config.runAsUser,      false);
+	UPSMON_DIRECTIVEX("DEBUG_MIN",      int,          config.debugMin,       false);
+	UPSMON_DIRECTIVEX("RUN_AS_USER",    std::string,  config.runAsUser,      true);
 	UPSMON_DIRECTIVEX("SHUTDOWNCMD",    std::string,  config.shutdownCmd,    true);
 	UPSMON_DIRECTIVEX("NOTIFYCMD",      std::string,  config.notifyCmd,      true);
-	UPSMON_DIRECTIVEX("POWERDOWNFLAG",  std::string,  config.powerDownFlag,  false);
+	UPSMON_DIRECTIVEX("POWERDOWNFLAG",  std::string,  config.powerDownFlag,  true);
 	UPSMON_DIRECTIVEX("MINSUPPLIES",    unsigned int, config.minSupplies,    false);
-	UPSMON_DIRECTIVEX("POLLFREQ",       unsigned int, config.poolFreq,       false);
-	UPSMON_DIRECTIVEX("POLLFREQALERT",  unsigned int, config.poolFreqAlert,  false);
-	UPSMON_DIRECTIVEX("HOSTSYNC",       unsigned int, config.hotSync,        false);
+	UPSMON_DIRECTIVEX("POLLFREQ",       unsigned int, config.pollFreq,       false);
+	UPSMON_DIRECTIVEX("POLLFREQALERT",  unsigned int, config.pollFreqAlert,  false);
+	UPSMON_DIRECTIVEX("POLLFAIL_LOG_THROTTLE_MAX", int, config.pollFailLogThrottleMax,  false);
+	UPSMON_DIRECTIVEX("OFFDURATION",    int,          config.offDuration,    false);
+	UPSMON_DIRECTIVEX("OBLBDURATION",   int,          config.oblbDuration,   false);
+	UPSMON_DIRECTIVEX("SHUTDOWNEXIT",   nut::BoolInt, config.shutdownExit,   false);
+
+	UPSMON_DIRECTIVEX("CERTPATH",       std::string,  config.certPath,       true);
+
+	// Spec says to write these as 0/1 integers
+	// and the macro requires Settable<>
+	// Mumbo-jumbo below for guaranteed casting to int
+	nut::BoolInt bi, bi2;
+	Settable<nut::BoolInt> bis;
+	int i;
+	// NOTE: After copy-assignments below (which inherit original strictness),
+	// need to add relaxed mode for 0/1 as false/true handling:
+	// bi.bool01 = true;
+	bi2.bool01 = false;	// strict mode for 0/1 as int handling
+	// Avoid static analysis concerns that the internal _value
+	// "may be used uninitialized in this function" (ETOOSMART):
+	bi = false;
+	bi2 = false;
+
+	if (config.certVerify.set()) {
+		bi = config.certVerify;
+		bi.bool01 = true;
+		i = bi;
+		bi2 = i;
+		bis = bi2;
+		UPSMON_DIRECTIVEX("CERTVERIFY",     nut::BoolInt, bis,                   false);
+	}
+
+	if (config.forceSsl.set()) {
+		bi = config.forceSsl;
+		bi.bool01 = true;
+		i = bi;
+		bi2 = i;
+		bis = bi2;
+		UPSMON_DIRECTIVEX("FORCESSL",       nut::BoolInt, bis,                   false);
+	}
+
+	UPSMON_DIRECTIVEX("HOSTSYNC",       unsigned int, config.hostSync,       false);
 	UPSMON_DIRECTIVEX("DEADTIME",       unsigned int, config.deadTime,       false);
 	UPSMON_DIRECTIVEX("RBWARNTIME",     unsigned int, config.rbWarnTime,     false);
 	UPSMON_DIRECTIVEX("NOCOMMWARNTIME", unsigned int, config.noCommWarnTime, false);
@@ -450,7 +658,29 @@ NutWriter::status_t UpsmonConfigWriter::writeConfig(const UpsmonConfiguration &
 # pragma GCC diagnostic pop
 #endif
 
-	#undef UPSMON_DIRECTIVEX
+#	undef UPSMON_DIRECTIVEX
+
+	// Certificate identity
+	if (config.certIdent.set()) {
+		std::string directive = serializeCertIdent(config.certIdent);
+
+		status_t status = writeDirective(directive);
+
+		if (NUTW_OK != status)
+			return status;
+	}
+
+	// Remote host(s) protected by specific certificates on their listeners
+	std::list<nut::CertHost>::const_iterator la_iter = config.certHosts.begin();
+
+	for (; la_iter != config.certHosts.end(); ++la_iter) {
+		std::string directive = serializeCertHost(*la_iter);
+
+		status_t status = writeDirective(directive);
+
+		if (NUTW_OK != status)
+			return status;
+	}
 
 	UpsmonConfiguration::NotifyType type;
 
@@ -532,7 +762,7 @@ NutWriter::status_t UpsdConfigWriter::writeConfig(const UpsdConfiguration & conf
 	 *  \param  arg_t      Directive argument implementation type
 	 *  \param  arg        Directive argument
 	 */
-	#define UPSD_DIRECTIVEX(name, arg_t, arg) \
+#	define UPSD_DIRECTIVEX(name, arg_t, arg) \
 		CONFIG_DIRECTIVEX(name, arg_t, arg, false)
 
 /* The "false" arg in macro below evaluates to `if (false) ...` after
@@ -548,10 +778,17 @@ NutWriter::status_t UpsdConfigWriter::writeConfig(const UpsdConfiguration & conf
 # pragma clang diagnostic push
 # pragma clang diagnostic ignored "-Wunreachable-code"
 #endif
-	UPSD_DIRECTIVEX("MAXAGE",    unsigned int, config.maxAge);
-	UPSD_DIRECTIVEX("MAXCONN",   unsigned int, config.maxConn);
-	UPSD_DIRECTIVEX("STATEPATH", std::string,  config.statePath);
-	UPSD_DIRECTIVEX("CERTFILE",  std::string,  config.certFile);
+	UPSD_DIRECTIVEX("DEBUG_MIN",                int,          config.debugMin);
+	UPSD_DIRECTIVEX("MAXAGE",                   unsigned int, config.maxAge);
+	UPSD_DIRECTIVEX("MAXCONN",                  unsigned int, config.maxConn);
+	UPSD_DIRECTIVEX("TRACKINGDELAY",            unsigned int, config.trackingDelay);
+	UPSD_DIRECTIVEX("ALLOW_NO_DEVICE",          bool,         config.allowNoDevice);
+	UPSD_DIRECTIVEX("ALLOW_NOT_ALL_LISTENERS",  bool,         config.allowNotAllListeners);
+	UPSD_DIRECTIVEX("DISABLE_WEAK_SSL",         bool,         config.disableWeakSsl);
+	CONFIG_DIRECTIVEX("STATEPATH",              std::string,  config.statePath, true);
+	CONFIG_DIRECTIVEX("CERTFILE",               std::string,  config.certFile, true);
+	CONFIG_DIRECTIVEX("CERTPATH",               std::string,  config.certPath, true);
+	UPSD_DIRECTIVEX("CERTREQUEST",              unsigned int, config.certRequestLevel);
 #ifdef __clang__
 # pragma clang diagnostic pop
 #endif
@@ -559,7 +796,17 @@ NutWriter::status_t UpsdConfigWriter::writeConfig(const UpsdConfiguration & conf
 # pragma GCC diagnostic pop
 #endif
 
-	#undef UPSD_DIRECTIVEX
+#	undef UPSD_DIRECTIVEX
+
+	// Certificate identity
+	if (config.certIdent.set()) {
+		std::string directive = serializeCertIdent(config.certIdent);
+
+		status_t status = writeDirective(directive);
+
+		if (NUTW_OK != status)
+			return status;
+	}
 
 	// Listen addresses
 	std::list<UpsdConfiguration::Listen>::const_iterator la_iter = config.listens.begin();
diff --git a/common/parseconf.c b/common/parseconf.c
index f7d6eec61b..41e376146f 100644
--- a/common/parseconf.c
+++ b/common/parseconf.c
@@ -485,6 +485,9 @@ static void parse_char(PCONF_CTX_t *ctx)
 		case STATE_COLLECTLITERAL:
 			ctx->state = collectliteral(ctx);
 			break;
+
+		default:
+			break;
 	}	/* switch */
 }
 
diff --git a/common/state.c b/common/state.c
index 6eaf18ab6c..51eb8db6ff 100644
--- a/common/state.c
+++ b/common/state.c
@@ -4,6 +4,7 @@
 	2003	Russell Kroll <rkroll@exploits.org>
 	2008	Arjen de Korte <adkorte-guest@alioth.debian.org>
 	2012	Arnaud Quette <arnaud.quette@free.fr>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -295,6 +296,7 @@ int state_setinfo(st_tree_t **nptr, const char *var, const char *val)
 
 		/* changes should be ignored */
 		if (node->flags & ST_FLAG_IMMUTABLE) {
+			upsdebugx(6, "%s: not changing immutable variable [%s]", __func__, var);
 			return 0;	/* no change */
 		}
 
@@ -357,8 +359,8 @@ int state_addenum(st_tree_t *root, const char *var, const char *val)
 	sttmp = state_tree_find(root, var);
 
 	if (!sttmp) {
-		upslogx(LOG_ERR, "state_addenum: base variable (%s) "
-			"does not exist", var);
+		upslogx(LOG_ERR, "%s: base variable (%s) "
+			"does not exist", __func__, var);
 		return 0;	/* failed */
 	}
 
@@ -400,8 +402,8 @@ int state_addrange(st_tree_t *root, const char *var, const int min, const int ma
 
 	/* sanity check */
 	if (min > max) {
-		upslogx(LOG_ERR, "state_addrange: min is superior to max! (%i, %i)",
-			min, max);
+		upslogx(LOG_ERR, "%s: min is superior to max! (%i, %i)",
+			__func__, min, max);
 		return 0;
 	}
 
@@ -409,8 +411,8 @@ int state_addrange(st_tree_t *root, const char *var, const int min, const int ma
 	sttmp = state_tree_find(root, var);
 
 	if (!sttmp) {
-		upslogx(LOG_ERR, "state_addrange: base variable (%s) "
-			"does not exist", var);
+		upslogx(LOG_ERR, "%s: base variable (%s) "
+			"does not exist", __func__, var);
 		return 0;	/* failed */
 	}
 
@@ -427,8 +429,8 @@ int state_setaux(st_tree_t *root, const char *var, const char *auxs)
 	sttmp = state_tree_find(root, var);
 
 	if (!sttmp) {
-		upslogx(LOG_ERR, "state_addenum: base variable (%s) "
-			"does not exist", var);
+		upslogx(LOG_ERR, "%s: base variable (%s) "
+			"does not exist", __func__, var);
 		return -1;	/* failed */
 	}
 
@@ -524,8 +526,8 @@ void state_setflags(st_tree_t *root, const char *var, size_t numflags, char **fl
 	sttmp = state_tree_find(root, var);
 
 	if (!sttmp) {
-		upslogx(LOG_ERR, "state_setflags: base variable (%s) "
-			"does not exist", var);
+		upslogx(LOG_ERR, "%s: base variable (%s) "
+			"does not exist", __func__, var);
 		return;
 	}
 
@@ -549,7 +551,7 @@ void state_setflags(st_tree_t *root, const char *var, size_t numflags, char **fl
 			continue;
 		}
 
-		upsdebugx(2, "Unrecognized flag [%s]", flag[i]);
+		upsdebugx(2, "%s: Unrecognized flag [%s]", __func__, flag[i]);
 	}
 }
 
diff --git a/common/str.c b/common/str.c
index 295f450804..df9f0734e8 100644
--- a/common/str.c
+++ b/common/str.c
@@ -627,3 +627,30 @@ int str_ends_with(const char *s, const char *suff) {
 
 	return (slen >= sufflen) && (!memcmp(s + slen - sufflen, suff, sufflen));
 }
+
+#ifndef HAVE_STRTOF
+# include <errno.h>
+# include <stdio.h>
+float strtof(const char *nptr, char **endptr)
+{
+	double d;
+	int i;
+
+	if (!nptr || !*nptr) {
+		errno = EINVAL;
+		return 0;
+	}
+
+	i = sscanf(nptr, "%f", &d);
+	if (i < 1) {
+		errno = EINVAL;
+		return 0;
+	}
+
+	if (endptr) {
+		*endptr = (char*)nptr + i;
+	}
+
+	return (float)d;
+}
+#endif
diff --git a/common/timegm_fallback.c b/common/timegm_fallback.c
new file mode 100644
index 0000000000..5c8a9bfc34
--- /dev/null
+++ b/common/timegm_fallback.c
@@ -0,0 +1,49 @@
+/* Fallback timegm() for systems that lack one.
+ * Algorithm: http://howardhinnant.github.io/date_algorithms.html
+ * https://stackoverflow.com/a/58037981/4715872
+ */
+
+#ifdef TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# ifdef HAVE_SYS_TIME_H
+#  include <sys/time.h>
+# else
+#  include <time.h>
+# endif
+#endif
+
+static int days_from_epoch_1970(int y, int m, int d)
+{
+    y -= m <= 2;
+    int era = y / 400;
+    int yoe = y - era * 400;                                   // [0, 399]
+    int doy = (153 * (m + (m > 2 ? -3 : 9)) + 2) / 5 + d - 1;  // [0, 365]
+    int doe = yoe * 365 + yoe / 4 - yoe / 100 + doy;           // [0, 146096]
+    return era * 146097 + doe - 719468;
+}
+
+/* It does not modify broken-down time */
+time_t timegm_fallback(struct tm const* t)     
+{
+    int year = t->tm_year + 1900;
+    int month = t->tm_mon;          // 0-11
+    int days_since_epoch_1970;
+
+    if (month > 11)
+    {
+        year += month / 12;
+        month %= 12;
+    }
+    else if (month < 0)
+    {
+        int years_diff = (11 - month) / 12;
+        year -= years_diff;
+        month += 12 * years_diff;
+    }
+    days_since_epoch_1970 = days_from_epoch_1970(year, month + 1, t->tm_mday);
+
+    return 60 * (60 * (24L * days_since_epoch_1970 + t->tm_hour) + t->tm_min) + t->tm_sec;
+}
+
diff --git a/conf/Makefile.am b/conf/Makefile.am
index 873d288324..fd384eebbc 100644
--- a/conf/Makefile.am
+++ b/conf/Makefile.am
@@ -22,7 +22,7 @@ SPELLCHECK_SRC = $(dist_sysconf_DATA) \
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/conf/hosts.conf.sample b/conf/hosts.conf.sample
index 24beb82956..37e561e78b 100644
--- a/conf/hosts.conf.sample
+++ b/conf/hosts.conf.sample
@@ -3,6 +3,9 @@
 # This file is used to control the CGI programs.  If you have not
 # installed them, you may safely ignore or delete this file.
 #
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
+#
 # -----------------------------------------------------------------------
 #
 # upsstats will use the list of MONITOR entries when displaying the
diff --git a/conf/nut.conf.sample b/conf/nut.conf.sample
index 71d5465d92..b58730480f 100644
--- a/conf/nut.conf.sample
+++ b/conf/nut.conf.sample
@@ -9,12 +9,19 @@
 #
 # IMPORTANT NOTES:
 #  This file is intended to be sourced by standard POSIX shell scripts
-#  (so there is no guaranteed `export VAR=VAL` syntax) and additionally
-#  by systemd on Linux (no guaranteed expansion of variables).
+#  (so there is no guaranteed `export VAR=VAL` syntax, while you may need
+#  to `export VAR` when sourcing it into init-scripts, for propagation to
+#  NUT programs eventually), and additionally by systemd on Linux (with no
+#  guaranteed expansion of variables -- only verbatim assignments).
+#
 #  You MUST NOT use spaces around the equal sign!
+#
 #  Practical support for this file and its settings currently varies between
 #  various OS packages and NUT sample scripts, but should converge over time.
 #
+#  Contents of this file should be pure ASCII (character codes not in range
+#  would be ignored with a warning message).
+#
 # See also: `man nut.conf` (usually in Manual pages Section 5,
 #           for Configuration files)
 #
@@ -86,3 +93,69 @@ MODE=none
 # via logs or console captures.
 # Set to `true` to avoid that trove of information, if you consider it noise.
 #POWEROFF_QUIET=true
+
+# The optional 'NUT_DEBUG_LEVEL' setting controls the default debugging message
+# verbosity passed to NUT daemons. As an environment variable, its priority sits
+# between that of 'DEBUG_MIN' setting of a driver and the command-line options.
+#NUT_DEBUG_LEVEL=0
+#export NUT_DEBUG_LEVEL
+
+# Optionally add current process ID to tags with debug-level identifiers.
+# This may be useful when many NUT daemons write to the same console or log
+# file, such as in containers/plugins for Home Assistant, storage appliances...
+#NUT_DEBUG_PID=true
+#export NUT_DEBUG_PID
+
+# Normally NUT can (attempt to) use the syslog or Event Log (WIN32), but the
+# environment variable 'NUT_DEBUG_SYSLOG' allows to bypass it, and perhaps keep
+# the daemons logging to stderr (useful e.g. in NUT Integration Test suite to
+# not pollute the OS logs, or in systemd where stderr and syslog both go into
+# the same journal). Recognized values:
+#  `stderr`  Disabled and background() keeps stderr attached
+#  `none`    Disabled and background() detaches stderr as usual
+#  `default`/unset/other   Not disabled
+#NUT_DEBUG_SYSLOG=stderr
+#export NUT_DEBUG_SYSLOG
+
+# Normally NUT can (attempt to) verify that the program file name matches the
+# name associated with a running process, when using PID files to send signals.
+# The `NUT_IGNORE_CHECKPROCNAME` boolean toggle allows to quickly skip such
+# verification, in case it causes problems (e.g. NUT programs were renamed and
+# do not match built-in expectations). This environment variable can also be
+# optionally set in init-scripts or service methods for `upsd`, `upsmon` and
+# NUT drivers/`upsdrvctl`.
+#NUT_IGNORE_CHECKPROCNAME=true
+#export NUT_IGNORE_CHECKPROCNAME
+
+# Optional flag to prevent daemons which can notify service management frameworks
+# (such as systemd) about passing their lifecycle milestones, to not report
+# loudly if they could NOT do so (e.g. running on a system without a framework,
+# or misconfigured so they could not report and the OS could eventually restart
+# the false-positively identified "unresponsive" service.
+# Currently such reports, done by default, help troubleshoot service start-up
+# and highlight that NUT sources (or package build) did not take advantage of
+# tighter OS service management framework integration (if one exists, so that
+# developers could focus on adding that). Reasons to set this flag could include
+# platforms without such a framework and not expecting one, although nagging
+# your favourite OS or contributing development to make it better is also a way.
+#NUT_QUIET_INIT_UPSNOTIFY=true
+#export NUT_QUIET_INIT_UPSNOTIFY
+
+##############################################################################
+# Variables that can be helpful more for tool scripting than service daemons
+##############################################################################
+
+# Optionally prevent `libupsclient` consumers (notoriously `upsc`, maybe
+# also `dummy-ups` driver or `nut-scanner` tool) from reporting whether
+# they have initialized SSL support -- or, loudly, failed to initialize
+# as it was not configured on this system.
+#NUT_QUIET_INIT_SSL=true
+#export NUT_QUIET_INIT_SSL
+
+# Optionally suppress NUT tool name and version banner (normally shown in most
+# NUT programs unilaterally, before processing any CLI options and possibly
+# failing due to that).
+# NOT recommended for services due to adverse troubleshooting impact, but may
+# be helpful in shell profiles or scripts which process NUT tool outputs.
+#NUT_QUIET_INIT_BANNER=true
+#export NUT_QUIET_INIT_BANNER
diff --git a/conf/ups.conf.sample b/conf/ups.conf.sample
index 3a37f82ad4..2eff376ca0 100644
--- a/conf/ups.conf.sample
+++ b/conf/ups.conf.sample
@@ -9,6 +9,9 @@
 #
 # ---
 #
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
+#
 # This is where you configure all the UPSes that this system will be
 # monitoring directly.  These are usually attached to serial ports, but
 # USB devices and SNMP devices are also supported.
@@ -172,6 +175,15 @@ maxretry = 3
 #           so it is not called by default. Yet others can be composite
 #           devices which use a non-zero interface to represent the UPS.
 #
+# usb_config_index=hexnum, usb_hid_rep_index=hexnum,
+# usb_hid_desc_index=hexnum, usb_hid_ep_in=hexnum, usb_hid_ep_out=hexnum:
+#           OPTIONAL. Force use of specific interface, endpoint, descriptor
+#           index etc. numbers, rather than defaulting to 0 (rarely other
+#           values in certain drivers for some devices known to use non-zero
+#           numbers). As a rule of thumb for `usb_hid_desc_index` discovery,
+#           you can see larger `wDescriptorLength` values (roughly 600+ bytes)
+#           in reports of `lsusb` or similar tools.
+#
 # default.<variable>: OPTIONAL. Set a default value for <variable> which is
 #           used in case the UPS doesn't provide a value, but which will be
 #           overwritten if a value is available from the UPS, e.g.:
diff --git a/conf/upsd.conf.sample b/conf/upsd.conf.sample
index dfbdf9e5ba..8fe3d1333d 100644
--- a/conf/upsd.conf.sample
+++ b/conf/upsd.conf.sample
@@ -7,6 +7,9 @@
 # Each entry below provides usage and default value.
 #
 # For more information, refer to upsd.conf manual page.
+#
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
 
 # =======================================================================
 # MAXAGE <seconds>
diff --git a/conf/upsd.users.sample b/conf/upsd.users.sample
index 60c42892bf..5fd4e2443c 100644
--- a/conf/upsd.users.sample
+++ b/conf/upsd.users.sample
@@ -4,6 +4,9 @@
 # Users are defined here, are given passwords, and their privileges are
 # controlled here too.  Since this file will contain passwords, keep it
 # secure, with only enough permissions for upsd to read it.
+#
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
 
 # --------------------------------------------------------------------------
 
diff --git a/conf/upsmon.conf.sample.in b/conf/upsmon.conf.sample.in
index bcda24a549..8f5a69b0e2 100644
--- a/conf/upsmon.conf.sample.in
+++ b/conf/upsmon.conf.sample.in
@@ -1,6 +1,14 @@
 # Network UPS Tools: example upsmon configuration
 #
 # This file contains passwords, so keep it secure.
+#
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
+#
+# A minimal configuration should include at least one MONITOR instruction,
+# MINSUPPLIES (may be 0 if this system is only monitoring other NUT servers),
+# and a POWERDOWNFLAG if this machine is a "primary" system connected to
+# the UPS and drives its late-shutdown power-off command in an emergency.
 
 # --------------------------------------------------------------------------
 # RUN_AS_USER <userid>
@@ -292,8 +300,13 @@ DEADTIME 15
 # For Windows setup use something like:
 # POWERDOWNFLAG "C:\\killpower"
 #
-# For Unix/Linux systems the legacy default is:
-# POWERDOWNFLAG /etc/killpower
+# For Unix/Linux systems the legacy common value is:
+#   POWERDOWNFLAG /etc/killpower
+# but nowadays you may want it in a temporary filesystem (e.g. under /run)
+#
+# WARNING: The 'upsmon' binary program does not have a built-in default,
+# so this setting MUST be specified in the configuration, in order for the
+# late shutdown integration to work on the particular primary-mode system!
 POWERDOWNFLAG "@POWERDOWNFLAG@"
 
 # --------------------------------------------------------------------------
@@ -320,9 +333,14 @@ POWERDOWNFLAG "@POWERDOWNFLAG@"
 # NOTIFYMSG BYPASS	"UPS %s: on bypass (powered, not protecting)"
 # NOTIFYMSG NOTBYPASS	"UPS %s: no longer on bypass"
 #
-# Note that %s is replaced with the identifier of the UPS in question.
+# A few messages not directly related to UPS events are also available:
+#
+# NOTIFYMSG SUSPEND_STARTING	"OS is entering sleep/suspend/hibernate mode"
+# NOTIFYMSG SUSPEND_FINISHED	"OS just finished sleep/suspend/hibernate mode, de-activating obsolete UPS readings to avoid an unfortunate shutdown"
 #
-# Possible values for <notify type>:
+# Note that %s (where used) is replaced with the identifier of the UPS in question.
+#
+# Meanings of some possible values for <notify type>:
 #
 # ONLINE   : UPS is back online
 # ONBATT   : UPS is on battery
@@ -362,6 +380,9 @@ POWERDOWNFLAG "@POWERDOWNFLAG@"
 # NOTIFYFLAG BYPASS	SYSLOG+WALL
 # NOTIFYFLAG NOTBYPASS	SYSLOG+WALL
 #
+# NOTIFYFLAG SUSPEND_STARTING	SYSLOG+WALL
+# NOTIFYFLAG SUSPEND_FINISHED	SYSLOG+WALL
+#
 # Possible values for the flags:
 #
 # SYSLOG - Write the message in the syslog
@@ -390,6 +411,29 @@ POWERDOWNFLAG "@POWERDOWNFLAG@"
 
 OFFDURATION 30
 
+# --------------------------------------------------------------------------
+# OBLBDURATION - put "OB LB" state into effect if it persists for this many
+# seconds
+#
+# NUT normally raises alarms for immediate shutdown (FSD) for consumers of an
+# UPS known to be on battery (OB) and achieving the low battery status (LB),
+# if that is their last remaining power source to satisfy their MINSUPPLIES
+# setting. In some special cases, users may want to delay raising the alarm
+# (using the OBLBDURATION option) at their discretion and risk of an ungraceful
+# shutdown.
+#
+# A non-positive value makes the FSD effect of detected "OB LB" state immediate.
+# Built-in default value is 0 (seconds).
+#
+# NOTE: If both `OBLBDURATION` and `HOSTSYNC` options are set on the same
+# (secondary) `upsmon` client system, and `HOSTSYNC` is shorter, it would be
+# effectively ignored: `upsmon` would wait for up to `OBLBDURATION` seconds
+# for the "OB LB" state to clear, and then the secondary client logic would
+# fall through to immediate shutdown. If the primary system issues an FSD on
+# this UPS, that would take an even higher-priority effect as soon as seen.
+#
+#OBLBDURATION 0
+
 # --------------------------------------------------------------------------
 # RBWARNTIME - replace battery warning time in seconds
 #
diff --git a/conf/upssched.conf.sample.in b/conf/upssched.conf.sample.in
index 541dea8234..79543cd714 100644
--- a/conf/upssched.conf.sample.in
+++ b/conf/upssched.conf.sample.in
@@ -1,5 +1,8 @@
 # Network UPS Tools - upssched.conf sample file
 #
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
+#
 # ============================================================================
 #
 # CMDSCRIPT <scriptname>
diff --git a/conf/upsset.conf.sample b/conf/upsset.conf.sample
index 3bb4850573..9825f787a0 100644
--- a/conf/upsset.conf.sample
+++ b/conf/upsset.conf.sample
@@ -5,6 +5,9 @@
 # the upsset.cgi program from running until you have assured it that you
 # have secured your web server's CGI directory.
 #
+# NOTE: Contents of this file should be pure ASCII (character codes
+# not in range would be ignored with a warning message).
+#
 # By default, your web server will probably let anyone access upsset.cgi
 # once it is installed.  This means that anyone could attempt to crack
 # upsd logins since they would appear to be coming from your web server,
diff --git a/configure.ac b/configure.ac
index 640c715840..fedaafbb64 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2,10 +2,31 @@ dnl +------------------------------------------------------------------+
 dnl | Network UPS Tools: configure.ac                                  |
 dnl +------------------------------------------------------------------+
 
+dnl # Support for older autoconf without m4_esyscmd_s
+m4_ifndef([m4_chomp_all], [m4_define([m4_chomp_all], [m4_format([[%.*s]], m4_bregexp(m4_translit([[$1]], [/], [/ ]), [/*$]), [$1])])])
+m4_ifndef([m4_esyscmd_s], [m4_define([m4_esyscmd_s], [m4_chomp_all(m4_esyscmd([$1]))])])
+
 dnl NUT version number is defined here, with a Git suffixed macro like
 dnl    NUT_VERSION_MACRO "2.7.4-2838-gdfc3ac08"
-dnl in include/nut_version.h (generated by make)
-AC_INIT([nut],[2.8.1.1],[https://github.com/networkupstools/nut/issues])
+dnl defined separately in include/nut_version.h (generated by make)
+dnl ...or not defined, for quicker rebuilds, depending on settings.
+dnl Old hard-coded approach (mangled a bit):
+dnl AC INIT([nut],[2.8.2.1],[https://github.com/networkupstools/nut/issues])
+dnl Note: srcdir is only set after AC INIT has completed, but $0 points
+dnl to the generated configure script which is part of dist tarball and
+dnl should be at source root too.
+dnl Note: this gets evaluated (script called) a lot of times during autoconf
+dnl but ends up as static strings in the generated configure script. It may
+dnl be beneficial to have a `version.m4` generated by `autogen.sh` and/or
+dnl shipped in a tarball, allowing for a singular include into configure.ac
+dnl See https://github.com/networkupstools/nut/issues/1949 for details.
+dnl Oddly, autoconf-2.69 on CentOS 7 both complains that AC INIT argument
+dnl is not a literal, and does contain expected values in the generated
+dnl script and include/config.h. A "pure" m4 solution would be quieter.
+AC_INIT([nut],
+    m4_esyscmd_s([NUT_VERSION_QUERY=VER50 "`dirname "$0"`/tools/gitlog2version.sh" 2>/dev/null]),
+    [https://github.com/networkupstools/nut/issues],[nut],
+    m4_esyscmd_s([NUT_VERSION_QUERY=URL "`dirname "$0"`/tools/gitlog2version.sh" 2>/dev/null]))
 dnl See docs/maintainer-guide.txt about releases - updating the version
 dnl above is a small part of the consistent ritual!
 
@@ -15,12 +36,25 @@ dnl the PDF documentation revision history via docs/docinfo.xml.in).
 dnl If the NUT codebase in this workspace is being developed and rebuilt
 dnl without reconfiguration, detailed version in the binaries will differ
 dnl (that one comes from the NUT_VERSION_MACRO from nut_version.h file).
-(command -v git >/dev/null 2>/dev/null) \
-&& NUT_SOURCE_GITREV="`(git describe --tags --match 'v[0-9]*.[0-9]*.[0-9]' --exclude '*-signed' --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*' 2>/dev/null || git describe --tags --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*' --exclude '*Windows*' --exclude '*IPM*' 2>/dev/null ) | sed -e 's/^v\([0-9]\)/\1/' -e 's,^.*/,,'`" \
-|| NUT_SOURCE_GITREV=""
+dnl # Example:   NUT_SOURCE_GITREV='2.8.2.695.1-696-g0e00f0777'
+NUT_SOURCE_GITREV="`NUT_VERSION_QUERY=DESC50 "${srcdir}/tools/gitlog2version.sh" 2>/dev/null`"
+
+dnl A true/false (literally) response that can be used for prettier messages
+dnl emitted by NUT code.
+NUT_SOURCE_GITREV_IS_RELEASE="`NUT_VERSION_QUERY=IS_RELEASE "${srcdir}/tools/gitlog2version.sh" 2>/dev/null`"
+AS_IF([$NUT_SOURCE_GITREV_IS_RELEASE], [NUT_SOURCE_GITREV_DEVREL="release"], [NUT_SOURCE_GITREV_DEVREL="development iteration"])
+
+dnl Semantic version of most-recent NUT release this code is derived from.
+dnl It may equal the NUT_SOURCE_GITREV and NUT_SOURCE_GITREV_NUMERIC, but
+dnl this situation is only expected if NUT_SOURCE_GITREV_IS_RELEASE==true.
+NUT_SOURCE_GITREV_SEMVER="`NUT_VERSION_QUERY=SEMVER "${srcdir}/tools/gitlog2version.sh" 2>/dev/null`"
 
 dnl Gitrev-based build identifier which can be used for e.g. PyPI uploads:
-NUT_SOURCE_GITREV_NUMERIC="`echo "${NUT_SOURCE_GITREV}" | sed -e 's/^v//' -e 's/-g.*$//' -e 's/-/./g'`"
+dnl # Example:   NUT_SOURCE_GITREV_NUMERIC='2.8.2.695.1.696'
+dnl #   NUT_SOURCE_GITREV_NUMERIC="`echo "${NUT_SOURCE_GITREV}" | sed -e 's/^v//' -e 's/-g.*$//' -e 's/-/./g'`"
+dnl # Without the commit-count since tag (dash-separated part):
+dnl # Example:   NUT_SOURCE_GITREV_NUMERIC='2.8.2.695.1'
+NUT_SOURCE_GITREV_NUMERIC="`echo "${NUT_SOURCE_GITREV}" | sed -e 's/^v//' -e 's/-g.*$//' -e 's/-@<:@0-9@:>@*$//'`"
 
 dnl Note: except for experiments, do not pass this into config.h - use
 dnl the NUT_VERSION_MACRO from nut_version.h instead. Developers may
@@ -81,7 +115,10 @@ AC_CONFIG_SRCDIR(server/upsd.c)
 AC_CONFIG_MACRO_DIR([m4])
 AS_IF([test x"${NUT_SOURCE_GITREV}" = x],
     [echo "Network UPS Tools version ${PACKAGE_VERSION}"],
-    [echo "Network UPS Tools version ${PACKAGE_VERSION} (${NUT_SOURCE_GITREV})"])
+    [AS_IF([test x"${NUT_SOURCE_GITREV}" = x"${PACKAGE_VERSION}"],
+        [echo "Network UPS Tools version ${PACKAGE_VERSION} ${NUT_SOURCE_GITREV_DEVREL}"],
+        [echo "Network UPS Tools version ${PACKAGE_VERSION} (${NUT_SOURCE_GITREV}) ${NUT_SOURCE_GITREV_DEVREL}"])
+    ])
 AC_CANONICAL_TARGET
 NUT_CHECK_OS
 NUT_STASH_WARNINGS
@@ -198,6 +235,8 @@ dnl # not configure time.
 dnl AC_DEFINE_UNQUOTED(UPS_VERSION, "${PACKAGE_VERSION}", [NUT version])
 
 dnl However, automatically define the tree version (mostly for AC_SUBST)
+dnl FIXME: This just picks first 3 chars, assuming single-digit components
+dnl  separated by a dot:
 TREE_VERSION="`echo ${PACKAGE_VERSION} | awk '{ print substr($0,1,3) }'`"
 AC_DEFINE_UNQUOTED(TREE_VERSION, "${TREE_VERSION}", [NUT tree version])
 
@@ -234,12 +273,30 @@ PIDPATH="/var/run"
 dnl Honour new LFS recommendations if applied on the build system:
 AS_IF([test -d "/run"], [PIDPATH="/run"])
 
+AC_CHECK_PROGS([GETENT], [getent], [])
+AC_CHECK_PROGS([ID], [id], [])
+
+PROBE_OS_USER="false"
+PROBE_OS_GROUP="false"
+AS_IF([test x"${GETENT}" != x], [
+	PROBE_OS_USER="${GETENT} passwd "
+	PROBE_OS_GROUP="${GETENT} group "
+	],[
+	AS_IF([test x"${ID}" != x], [
+		PROBE_OS_USER="${ID} -u "
+		PROBE_OS_GROUP="${ID} -g "
+		],[
+		AC_MSG_WARN([Can not check existence of user and group accounts on this system])
+		])
+	]
+)
+
 dnl Defaults for respective configure options below
 dnl Note these defaults may change further below depending on OS and
 dnl certain other configure options (e.g. "in-place replacement")
 RUN_AS_USER="nobody"
 RUN_AS_GROUP="nobody"
-AS_IF([test -n "`getent group nogroup`" && ! test -n "`getent group "${RUN_AS_GROUP}"`"],
+AS_IF([test -n "`${PROBE_OS_GROUP} nogroup`" && ! test -n "`${PROBE_OS_GROUP} "${RUN_AS_GROUP}"`"],
     [RUN_AS_GROUP="nogroup"]
 )
 
@@ -252,14 +309,37 @@ AS_CASE([${target_os}],
 
 cgiexecdir='${exec_prefix}/cgi-bin'
 driverexecdir='${exec_prefix}/bin'
+dnl Note: htmldir per se is originally for nut-cgi resources
 htmldir='${prefix}/html'
+htmldocdir='${docdir}/html-doc'
+htmlmandir='${docdir}/html-man'
 pkgconfigdir='${libdir}/pkgconfig'
-auglensdir='/usr/share/augeas/lenses/dist'
-if test ! -d "${auglensdir}"; then
-   auglensdir='/usr/share/augeas/lenses'
-   if test ! -d "${auglensdir}"; then
-      auglensdir=''
-   fi
+
+dnl Detection of augeas lens dirs is a bit troublesome, since
+dnl they (if present) reside in location not controlled by NUT.
+dnl Try detecting based on build parameters, or fall back to
+dnl hard-coded default location (may break e.g. distcheck).
+dnl Note it would not work too well for "/usr/local/ups" :)
+auglensdir='${datarootdir}/augeas/lenses/dist'
+conftemp="${auglensdir}"
+eval conftemp=\"${conftemp}\"
+eval conftemp=\"${conftemp}\"
+
+if test ! -d "${conftemp}"; then
+    auglensdir='${datarootdir}/augeas/lenses'
+    conftemp="${auglensdir}"
+    eval conftemp=\"${conftemp}\"
+    eval conftemp=\"${conftemp}\"
+
+    if test ! -d "${conftemp}"; then
+        auglensdir='/usr/share/augeas/lenses/dist'
+        if test ! -d "${auglensdir}"; then
+            auglensdir='/usr/share/augeas/lenses'
+            if test ! -d "${auglensdir}"; then
+                auglensdir=''
+            fi
+        fi
+    fi
 fi
 
 dnl ### NUT_CHECK_LIBREGEX ### Detect below as part of libusb etc.
@@ -519,7 +599,7 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
             [for F in "${udevdir}/rules.d"/*-nut-*.rules ; do
                 if test -s "$F" ; then
                     nut_inplace_group="`grep GROUP= "$F" | head -1 | sed 's,^.* GROUP="*\(.*\)"*.*$,\1,'`" \
-                    && test -n "`getent group "${nut_inplace_group}"`" \
+                    && test -n "`${PROBE_OS_GROUP} "${nut_inplace_group}"`" \
                     && AC_MSG_RESULT([Got from ${F}]) \
                     && break \
                     || nut_inplace_group=""
@@ -528,8 +608,8 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
             ])
 
         AS_IF([test -z "${nut_inplace_group}"],
-            [AS_IF([test -n "`getent group nut`"], [nut_inplace_group="nut"],
-                [AS_IF([test -n "`getent group ups`"], [nut_inplace_group="ups"])])])
+            [AS_IF([test -n "`${PROBE_OS_GROUP} nut`"], [nut_inplace_group="nut"],
+                [AS_IF([test -n "`${PROBE_OS_GROUP} ups`"], [nut_inplace_group="ups"])])])
 
         AS_IF([test -n "${nut_inplace_group}"], [
             AC_MSG_RESULT([${nut_inplace_group}])
@@ -553,7 +633,7 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
                 `grep -E '^ *##*  *RUN_AS_USER' "${CONFPATH}/upsmon.conf" | awk '{print $3}'`\
             ; do \
                 AS_IF([test -z "${nut_inplace_user}"], [
-                    test -n "`getent passwd "${nut_inplace_user}"`" \
+                    test -n "`${PROBE_OS_USER} "${nut_inplace_user}"`" \
                     && AC_MSG_RESULT([Got from ${CONFPATH}/upsmon.conf]) \
                     || nut_inplace_user=""])
              done
@@ -566,7 +646,7 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
                 `grep -E '^ *##*  *RUN_AS_USER' "${CONFPATH}/upsmon.conf.sample" | awk '{print $3}'`\
             ; do \
                 AS_IF([test -z "${nut_inplace_user}"], [
-                    test -n "`getent passwd "${nut_inplace_user}"`" \
+                    test -n "`${PROBE_OS_USER} "${nut_inplace_user}"`" \
                     && AC_MSG_RESULT([Got from ${CONFPATH}/upsmon.conf]) \
                     || nut_inplace_user=""])
              done
@@ -584,15 +664,15 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
         ; do
             AS_IF([test -z "${nut_inplace_user}" && test -s "$F"],
                 [nut_inplace_user="`grep -E '^ *nutuser=' "$F" | sed 's,^ *nutuser=,,'`" \
-                && test -n "`getent passwd "${nut_inplace_user}"`" \
+                && test -n "`${PROBE_OS_USER} "${nut_inplace_user}"`" \
                 && AC_MSG_RESULT([Got from $F]) \
                 || nut_inplace_user=""
             ])
         done
 
         AS_IF([test -z "${nut_inplace_user}"],
-            [AS_IF([test -n "`getent passwd nut`"], [nut_inplace_user="nut"],
-                [AS_IF([test -n "`getent passwd ups`"], [nut_inplace_user="ups"])])])
+            [AS_IF([test -n "`${PROBE_OS_USER} nut`"], [nut_inplace_user="nut"],
+                [AS_IF([test -n "`${PROBE_OS_USER} ups`"], [nut_inplace_user="ups"])])])
 
         AS_IF([test -n "${nut_inplace_user}"], [
             AC_MSG_RESULT([${nut_inplace_user}])
@@ -617,6 +697,10 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
         test -n "${CONFIG_CXXFLAGS-}" || CONFIG_CXXFLAGS=" "
         export CONFIG_CFLAGS
         export CONFIG_CXXFLAGS
+
+        AC_MSG_NOTICE([Moving config.log of the original invocation to config.log.inplace-outer just before exec...])
+        mv -f config.log config.log.inplace-outer || true
+
         eval exec "$0" $CONFIG_FLAGS_DEPLOYED $CONFIG_FLAGS --disable-inplace-runtime
     ],[
         AC_MSG_NOTICE([No CONFIG_FLAGS were reported or discovered from existing NUT deployment (if any); restarting script for a clean run])
@@ -627,6 +711,10 @@ AS_IF([test x"$nut_enable_inplace_runtime" = xyes -a x"${NUT_VERSION_DEPLOYED-}"
         test -n "${CONFIG_CXXFLAGS-}" || CONFIG_CXXFLAGS=" "
         export CONFIG_CFLAGS
         export CONFIG_CXXFLAGS
+
+        AC_MSG_NOTICE([Moving config.log of the original invocation to config.log.inplace-outer just before exec...])
+        mv -f config.log config.log.inplace-outer || true
+
         AC_MSG_NOTICE([exec "$0" $CONFIG_FLAGS --disable-inplace-runtime])
         eval exec "$0" $CONFIG_FLAGS --disable-inplace-runtime
     ])
@@ -655,7 +743,10 @@ NUT_ARG_ENABLE([keep_nut_report_feature],
 
 AS_IF([test x"${NUT_SOURCE_GITREV}" = x],
     [NUT_REPORT([configured version], [${PACKAGE_VERSION}])],
-    [NUT_REPORT([configured version], [${PACKAGE_VERSION} (${NUT_SOURCE_GITREV})])])
+    [AS_IF([test x"${NUT_SOURCE_GITREV}" = x"${PACKAGE_VERSION}"],
+        [NUT_REPORT([configured version], [${PACKAGE_VERSION} ${NUT_SOURCE_GITREV_DEVREL}])],
+        [NUT_REPORT([configured version], [${PACKAGE_VERSION} (${NUT_SOURCE_GITREV}) ${NUT_SOURCE_GITREV_DEVREL}])])
+    ])
 
 dnl Note: the compiler/pragma/attr methods below are custom for NUT codebase:
 NUT_COMPILER_FAMILY
@@ -677,17 +768,34 @@ AX_C_PRAGMAS
 AX_C___ATTRIBUTE__
 AX_C_PRINTF_STRING_NULL
 
+dnl Check if the system provides a boolean type and how it is spelled
+NUT_CHECK_BOOL
+
 dnl All current systems provide time.h; it need not be checked for.
 dnl Not all systems provide sys/time.h, but those that do, all allow
 dnl you to include it and time.h simultaneously.
 dnl NUT codebase provides the include/timehead.h to wrap these nuances.
-AC_CHECK_HEADERS_ONCE([sys/time.h time.h sys/types.h sys/socket.h netdb.h])
+AC_CHECK_HEADERS_ONCE([sys/time.h time.h sys/types.h])
 dnl ###obsolete### AC_HEADER_TIME
 AS_IF([test "$ac_cv_header_sys_time_h" = yes],
     [AC_DEFINE([TIME_WITH_SYS_TIME],[1],[Define to 1 if you can safely include both <sys/time.h>
          and <time.h>.  This macro is deemed obsolete by autotools.])
     ], [])
 
+CODE_TIMEINCL="
+#ifdef TIME_WITH_SYS_TIME
+# include <sys/time.h>
+# include <time.h>
+#else
+# ifdef HAVE_SYS_TIME_H
+#  include <sys/time.h>
+# else
+#  include <time.h>
+# endif
+#endif
+"
+
+AC_CHECK_HEADERS_ONCE([fcntl.h sys/stat.h sys/socket.h netdb.h])
 AC_CHECK_FUNCS(flock lockf fcvt fcvtl dup dup2 abs_val abs)
 
 AC_CHECK_HEADER([float.h],
@@ -761,9 +869,30 @@ SEMLIBS=""
 AC_CHECK_HEADER([semaphore.h],
     [AC_DEFINE([HAVE_SEMAPHORE_H], [1],
         [Define to 1 if you have <sys/semaphore.h>.])
-     AC_MSG_CHECKING([for sem_t, sem_init() and sem_destroy()])
+
      AC_LANG_PUSH([C])
-     AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
+     myLIBS="${LIBS}"
+     LIBS=""
+     SEMLIBS_LRT=""
+
+     dnl Solaris 8 builds complain about indirect dependency involved:
+     dnl   sem_init   nut_scanner-nut-scanner.o
+     dnl   (symbol belongs to implicit dependency /usr/lib/librt.so.1)
+     AC_SEARCH_LIBS([sem_init], [pthread], [], [
+	unset ac_cv_search_sem_init
+	AC_SEARCH_LIBS([sem_init], [pthread], [SEMLIBS_LRT=" -lrt"], [], [-lrt])])
+     AC_SEARCH_LIBS([sem_open], [pthread], [], [
+	unset ac_cv_search_sem_open
+	AC_SEARCH_LIBS([sem_open], [pthread], [SEMLIBS_LRT=" -lrt"], [], [-lrt])])
+
+     AS_CASE([${ac_cv_search_sem_init}], [no*], [], [SEMLIBS="${ac_cv_search_sem_init}"])
+     AS_CASE([${ac_cv_search_sem_open}], [no*], [], ["${SEMLIBS}"], [], [SEMLIBS="${ac_cv_search_sem_open}"])
+     SEMLIBS="${SEMLIBS}${SEMLIBS_LRT}"
+
+     LIBS="${SEMLIBS}"
+
+     AC_MSG_CHECKING([for sem_t, sem_init() and sem_destroy()])
+     AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([
 #include <semaphore.h>
 ],
 [sem_t semaphore;
@@ -773,18 +902,38 @@ sem_destroy(&semaphore);
  * normally check for non-zero meaning to look in errno */
 ]
         )],
-        [AC_DEFINE([HAVE_SEMAPHORE], [1],
-            [Define to 1 if you have <sys/semaphore.h> with usable sem_t sem_init() and sem_destroy().])
+        [AC_DEFINE([HAVE_SEMAPHORE_UNNAMED], [1],
+            [Define to 1 if you have <sys/semaphore.h> with usable sem_t, sem_init() and sem_destroy() for unnamed semaphores.])
          AC_MSG_RESULT([ok])
+        ],
+        [AC_MSG_RESULT([no])]
+     )
 
-	 dnl Solaris 8 builds complain about indirect dependency involved:
-	 dnl   sem_init   nut_scanner-nut-scanner.o
-	 dnl   (symbol belongs to implicit dependency /usr/lib/librt.so.1)
-
-	 AC_CHECK_LIB(rt, sem_init, SEMLIBS="-lrt")
+     AC_MSG_CHECKING([for sem_t, sem_open() and sem_close()])
+     AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
+#include <semaphore.h>
+#ifdef HAVE_FCNTL_H
+# include <fcntl.h>           /* For O_* constants */
+#endif
+#ifdef SYS_STAT_H
+# include <sys/stat.h>        /* For mode constants */
+#endif
+],
+[sem_t *semaphore = sem_open("/s", O_CREAT, 0644, 4);
+if (semaphore != SEM_FAILED)
+    sem_close(semaphore);
+/* Do not care about actual return value in this test,
+ * normally check for non-zero meaning to look in errno */
+]
+        )],
+        [AC_DEFINE([HAVE_SEMAPHORE_NAMED], [1],
+            [Define to 1 if you have <sys/semaphore.h> with usable sem_t, sem_open() and sem_close() for named semaphores.])
+         AC_MSG_RESULT([ok])
         ],
         [AC_MSG_RESULT([no])]
      )
+
+     LIBS="${myLIBS}"
      AC_LANG_POP([C])
     ]
 )
@@ -813,29 +962,44 @@ dnl# 	[], [AC_MSG_WARN([Required C library routine not found; try adding __EXTEN
 dnl These appear with CFLAGS="-std=c99 -D_POSIX_C_SOURCE=200112L":
 dnl# Methods below currently do not cause build errors for C99+ modes so are
 dnl# not tested as thoroughly as those further below:
-AC_CHECK_FUNCS(strtok_r fileno sigemptyset sigaction,
-	[], [AC_MSG_WARN([Required C library routine not found; try adding -D_POSIX_C_SOURCE=200112L])])
+AC_CHECK_FUNCS(strtof strtok_r fileno sigemptyset sigaction,
+	[], [AC_MSG_WARN([Required C library routine not found by linker; try adding -D_POSIX_C_SOURCE=200112L])])
 
 dnl For these we have a fallback implementation via the other,
 dnl if at least one is available, so initial check is quiet.
 dnl This typically pops up in POSIX vs. Windows builds:
-AC_CHECK_FUNCS(localtime_r localtime_s gmtime_r gmtime_s,
-	[], [])
+dnl Reminder: the former checks for declarations in headers,
+dnl the latter checks if known libraries suffice for linker.
+dnl Might need AC_CHECK_LIBS as well to populate the list with
+dnl known variants?
+AC_CHECK_DECLS([localtime_r, localtime_s, gmtime_r, gmtime_s, timegm, _mkgmtime], [], [], [$CODE_TIMEINCL])
+AC_CHECK_FUNCS(localtime_r localtime_s gmtime_r gmtime_s timegm _mkgmtime, [], [])
 
 AC_MSG_CHECKING([for at least one gmtime implementation])
-AS_IF([test x"${ac_cv_func_gmtime_s}-${ac_cv_func_gmtime_r}" = "xno-no"], [
+AS_IF([test x"${ac_cv_func_gmtime_s}-${ac_cv_func_gmtime_r}" = "xno-no" && test x"${ac_cv_have_decl_gmtime_s}-${ac_cv_have_decl_gmtime_r}" = "xno-no"], [
 	AC_MSG_RESULT([no])
-	AC_MSG_WARN([Required C library routine gmtime_s nor gmtime_r was not found; try adding -D_POSIX_C_SOURCE=200112L])
+	AC_MSG_WARN([Required C library routine gmtime_s nor gmtime_r was not found by linker nor in headers; try adding -D_POSIX_C_SOURCE=200112L and/or -D_POSIX_THREAD_SAFE_FUNCTIONS=200112L])
 	],[
 	AC_MSG_RESULT([yes])
 	])
 
 AC_MSG_CHECKING([for at least one localtime implementation])
-AS_IF([test x"${ac_cv_func_localtime_s}-${ac_cv_func_localtime_r}" = "xno-no"], [
+AS_IF([test x"${ac_cv_func_localtime_s}-${ac_cv_func_localtime_r}" = "xno-no" && test x"${ac_cv_have_decl_localtime_s}-${ac_cv_have_decl_localtime_r}" = "xno-no"], [
+	AC_MSG_RESULT([no])
+	AC_MSG_WARN([Required C library routine localtime_s nor localtime_r was not found by linker nor in headers; try adding -D_POSIX_C_SOURCE=200112L and/or -D_POSIX_THREAD_SAFE_FUNCTIONS=200112L])
+	],[
+	AC_MSG_RESULT([yes])
+	])
+
+AC_MSG_CHECKING([for at least one timegm implementation])
+AS_IF([test x"${ac_cv_func_timegm}-${ac_cv_func__mkgmtime}" = "xno-no" && test x"${ac_cv_have_decl_timegm}-${ac_cv_have_decl__mkgmtime}" = "xno-no"], [
 	AC_MSG_RESULT([no])
-	AC_MSG_WARN([Required C library routine localtime_s nor localtime_r was not found; try adding -D_POSIX_C_SOURCE=200112L])
+	AC_MSG_WARN([Required C library routine timegm nor _mkgmtime was not found by linker nor in headers])
+	AC_DEFINE_UNQUOTED([WANT_TIMEGM_FALLBACK], [1], [Defined if we want to use timegm_fallback()])
+	AM_CONDITIONAL([WANT_TIMEGM_FALLBACK], [true])
 	],[
 	AC_MSG_RESULT([yes])
+	AM_CONDITIONAL([WANT_TIMEGM_FALLBACK], [false])
 	])
 
 AC_LANG_PUSH([C])
@@ -936,16 +1100,7 @@ AC_CACHE_CHECK([for strptime(s1,s2,tm)],
     [ac_cv_func_strptime],
     [AX_RUN_OR_LINK_IFELSE(
         [AC_LANG_PROGRAM([$CODE_STRINGINCL
-#ifdef TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# ifdef HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
+$CODE_TIMEINCL
 ],
             [struct tm tm;
 char *date = "12/30/1999";
@@ -965,16 +1120,7 @@ AC_CACHE_CHECK([for clock_gettime(CLOCK_MONOTONIC,ts)],
     [ac_cv_func_clock_gettime],
     [AX_RUN_OR_LINK_IFELSE(
         [AC_LANG_PROGRAM([$CODE_STRINGINCL
-#ifdef TIME_WITH_SYS_TIME
-# include <sys/time.h>
-# include <time.h>
-#else
-# ifdef HAVE_SYS_TIME_H
-#  include <sys/time.h>
-# else
-#  include <time.h>
-# endif
-#endif
+$CODE_TIMEINCL
 ],
             [struct timespec monoclock_ts;
 int got_monoclock = clock_gettime(CLOCK_MONOTONIC, &monoclock_ts);
@@ -1036,6 +1182,12 @@ AC_CHECK_HEADER([sys/select.h],
     [AC_DEFINE([HAVE_SYS_SELECT_H], [1],
         [Define to 1 if you have <sys/select.h>.])])
 
+AC_CHECK_HEADER([unistd.h],
+    [AC_DEFINE([HAVE_UNISTD_H], [1],
+        [Define to 1 if you have <unistd.h>.])])
+
+AC_CHECK_FUNCS(readlink)
+
 AC_CACHE_CHECK([for suseconds_t],
     [ac_cv_type_suseconds_t],
     [AC_COMPILE_IFELSE(
@@ -1094,6 +1246,68 @@ AS_IF([test x"${ac_cv_func_usleep}" = xyes],
     [AC_MSG_WARN([Required C library routine usleep not found; try adding -D_POSIX_C_SOURCE=200112L])]
     )
 
+dnl OpenBSD (at least) methods to query process info, per
+dnl https://github.com/openbsd/src/blob/master/bin/ps/ps.c
+dnl https://kaashif.co.uk/2015/06/18/how-to-get-a-list-of-processes-on-openbsd-in-c/
+BSDKVMPROCLIBS=""
+myLIBS="$LIBS"
+LIBS="$LIBS -lkvm"
+AC_CACHE_CHECK([for BSD KVM process info libs],
+    [ac_cv_lib_bsd_kvm_proc],
+    [AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM([[
+#include <stdio.h>
+#include <kvm.h>
+#include <limits.h>
+#include <sys/param.h>
+#include <sys/sysctl.h>
+        ]],
+            [[
+    char errbuf[_POSIX2_LINE_MAX];
+    kvm_t *kernel = kvm_openfiles(NULL, NULL, NULL, KVM_NO_FILES, errbuf);
+    int nentries = 0;
+    struct kinfo_proc *kinfo = kvm_getprocs(kernel, KERN_PROC_ALL, 0, sizeof(struct kinfo_proc), &nentries);
+    int i;
+    for (i = 0; i < nentries; ++i) {
+        printf("%s\n", kinfo[i].p_comm);
+    }
+/* autoconf adds ";return 0;" */
+/* we hope the code above fails if type is not defined or range is not sufficient */
+]])],
+        [ac_cv_lib_bsd_kvm_proc=yes
+        BSDKVMPROCLIBS="-lkvm"
+        ], [ac_cv_lib_bsd_kvm_proc=no]
+    )])
+LIBS="$myLIBS"
+
+AS_IF([test x"${ac_cv_lib_bsd_kvm_proc}" = xyes],
+    [AC_DEFINE([HAVE_LIB_BSD_KVM_PROC], 1, [defined if we have libs, includes and methods for BSD KVM process info])]
+    )
+
+dnl https://github.com/illumos/illumos-gate/blob/master/usr/src/uts/common/sys/procfs.h#L318
+dnl https://github.com/illumos/illumos-gate/blob/master/usr/src/cmd/ps/ps.c
+AC_CACHE_CHECK([for Solaris/illumos process info libs],
+    [ac_cv_lib_illumos_proc],
+    [AC_LINK_IFELSE(
+        [AC_LANG_PROGRAM([[
+#include <stdio.h>
+#include <procfs.h>
+        ]],
+            [[
+    psinfo_t info;
+    printf("%s", info.pr_fname)
+/* autoconf adds ";return 0;" */
+/* we hope the code above fails if type is not defined or range is not sufficient */
+]])],
+        [ac_cv_lib_illumos_proc=yes
+        ], [ac_cv_lib_illumos_proc=no]
+    )])
+LIBS="$myLIBS"
+
+AS_IF([test x"${ac_cv_lib_illumos_proc}" = xyes],
+    [AC_DEFINE([HAVE_LIB_ILLUMOS_PROC], 1, [defined if we have libs, includes and methods for Solaris/illumos process info])]
+    )
+
 AC_LANG_POP([C])
 
 dnl These routines' arg types differ in strict C standard mode
@@ -1108,13 +1322,36 @@ AC_MSG_CHECKING([whether ln -sr works])
 dnl We need to relative-symlink some files. Or hardlink. Or copy...
 LN_S_R="cp -pR"
 if test "$as_ln_s" = "ln -s" ; then
-    LN_S_R="ln"
+    _abs_srcdir="`cd "${srcdir}" && pwd`" || _abs_srcdir=""
+    _abs_builddir="`pwd`"
+    dnl AC_MSG_NOTICE([srcdir='${srcdir}' _abs_srcdir='${_abs_srcdir}' _abs_builddir='${_abs_builddir}'])
+    if test x"${_abs_srcdir}" = x"${_abs_builddir}" ; then
+        LN_S_R="ln"
+    else
+        dnl NOTE: Here we check equality of the file systems by the
+        dnl devices they are mounted from (first column in df output):
+        _fs_srcdir="`df "${_abs_srcdir}" | tail -1 | awk '{print $1}'`" || fs_srcdir="XXXs"
+        _fs_builddir="`df "${_abs_builddir}" | tail -1 | awk '{print $1}'`" || fs_builddir="XXXb"
+        dnl AC_MSG_NOTICE([_fs_srcdir='${_fs_srcdir}' _fs_builddir='${_fs_builddir}'])
+        if test x"${_fs_srcdir}" = x"${_fs_builddir}" ; then
+            LN_S_R="ln"
+        else
+            dnl Source and build areas are in different filesystems,
+            dnl can not hardlink - keep copying approach in place
+            AC_MSG_NOTICE([Source and build areas are in different filesystems, or we could not detect this for sure - avoiding hardlinks])
+        fi
+        unset _fs_srcdir _fs_builddir
+    fi
+    unset _abs_srcdir _abs_builddir
+
+    dnl Explore GNU ln (or compatible) with relative symlink support
     DIR1="$(mktemp -d "dir1.XXXXXXX")" && \
     DIR2="$(mktemp -d "dir2.XXXXXXX")" && \
     touch "${DIR1}/a" && \
     $as_ln_s -r "${DIR1}/a" "${DIR2}/b" && \
     ls -la "${DIR2}/b" | grep '\.\./' > /dev/null && \
     LN_S_R="$as_ln_s -r"
+
     rm -rf "${DIR1}" "${DIR2}"
 fi
 AC_SUBST([LN_S_R], [${LN_S_R}])
@@ -1352,8 +1589,144 @@ AS_IF([test x"${ac_cv_struct_pollfd}" = xyes],
     ]
     )
 
+NETLIBS_GETADDRS=""
+dnl For `nut-scanner -m auto` modes, see also:
+dnl https://stackoverflow.com/a/41151132/4715872
+dnl https://learn.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getadaptersaddresses (since ~Windows Vista)
+dnl https://learn.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getadaptersinfo (before Windows XP; not recommended later)
+dnl Must check in global context, to have it not-defined where appropriate too
+NUT_CHECK_HEADER_IPHLPAPI
+AC_CHECK_HEADERS_ONCE([ifaddrs.h netinet/in.h net/if.h])
+AC_CHECK_FUNCS([getifaddrs], [], [
+    AS_CASE([${target_os}],
+        [*mingw*], [
+            dnl Check for GetAdaptersAddresses / GetAdaptersInfo
+            AS_IF([test x"${nut_cv_header_iphlpapi_h}" = xyes], [
+
+                myIPHLPAPI_TEST_HEADERS='
+#if HAVE_WINDOWS_H
+# undef inline
+# ifndef WIN32_LEAN_AND_MEAN
+#  define WIN32_LEAN_AND_MEAN
+# endif
+# include <windows.h>
+# if HAVE_WINSOCK2_H
+#  include <winsock2.h>
+# endif
+# if HAVE_IPHLPAPI_H
+#  include <iphlpapi.h>
+# endif
+#endif
+#include <stdio.h>
+'
+
+                myIPHLPAPI_TEST_GAA='
+/* ULONG GetAdaptersAddresses(ULONG af, ULONG flags, void* rsvd, PIP_ADAPTER_ADDRESSES addrs, PULONG sizeptr); */
+IP_ADAPTER_ADDRESSES buf@<:@8@:>@;
+ULONG bufsz = sizeof(buf);
+printf("%ld ", GetAdaptersAddresses(AF_UNSPEC, GAA_FLAG_SKIP_MULTICAST, NULL, buf, &bufsz));
+printf("%ld ", GetAdaptersAddresses(AF_INET, GAA_FLAG_SKIP_DNS_SERVER, NULL, buf, &bufsz));
+printf("%ld ", GetAdaptersAddresses(AF_INET6, GAA_FLAG_SKIP_ANYCAST, NULL, buf, &bufsz))
+/* autoconf adds ";return 0;" */
+'
+
+                AC_CACHE_CHECK([for GetAdaptersAddresses() with IPv4 and IPv6 support],
+                    [ac_cv_func_GetAdaptersAddresses],
+                    [AC_LANG_PUSH([C])
+                    dnl e.g. add "-lws2_32" for mingw builds, maybe "-liphlpapi"
+                    dnl the NETLIBS are set by NUT_CHECK_SOCKETLIB above
+                    SAVED_LIBS="$LIBS"
+                    LIBS="$LIBS $NETLIBS"
+                    AX_RUN_OR_LINK_IFELSE(
+                        [AC_LANG_PROGRAM(
+                            [${myIPHLPAPI_TEST_HEADERS}],
+                            [${myIPHLPAPI_TEST_GAA}])],
+                        [ac_cv_func_GetAdaptersAddresses=yes
+                        ], [
+                            NETLIBS_GETADDRS="-liphlpapi"
+                            LIBS="$LIBS $NETLIBS $NETLIBS_GETADDRS"
+                            AX_RUN_OR_LINK_IFELSE(
+                                [AC_LANG_PROGRAM(
+                                    [${myIPHLPAPI_TEST_HEADERS}],
+                                    [${myIPHLPAPI_TEST_GAA}])],
+                                [
+                                    ac_cv_func_GetAdaptersAddresses=yes
+                                ], [
+                                    ac_cv_func_GetAdaptersAddresses=no
+                                    NETLIBS_GETADDRS=""
+                                ]
+                            )
+                        ]
+                    )
+                    AC_LANG_POP([C])
+                    LIBS="$SAVED_LIBS"
+                ])
+                AS_IF([test x"${ac_cv_func_GetAdaptersAddresses}" = xyes],
+                    [AC_DEFINE([HAVE_GETADAPTERSADDRESSES], 1, [defined if system has the GetAdaptersAddresses() method])],
+                    [dnl AC_MSG_WARN([WIN32 library routine GetAdaptersAddresses() not found])
+                     AS_CASE([${target_os}],
+                         [*mingw*], [AC_MSG_WARN([Windows antivirus might block this test])]
+                         )
+                    ]
+                    )
+
+                myIPHLPAPI_TEST_GAI='
+/* ULONG GetAdaptersInfo(PIP_ADAPTER_INFO addrs, PULONG sizeptr); */
+IP_ADAPTER_INFO buf@<:@8@:>@;
+ULONG bufsz = sizeof(buf);
+printf("%ld ", GetAdaptersInfo(buf, &bufsz))
+/* autoconf adds ";return 0;" */
+'
+
+                AC_CACHE_CHECK([for GetAdaptersInfo() with IPv4 only support],
+                    [ac_cv_func_GetAdaptersInfo],
+                    [AC_LANG_PUSH([C])
+                    dnl e.g. add "-lws2_32" for mingw builds
+                    dnl the NETLIBS are set by NUT_CHECK_SOCKETLIB above
+                    SAVED_LIBS="$LIBS"
+                    LIBS="$LIBS $NETLIBS $NETLIBS_GETADDRS"
+                    AX_RUN_OR_LINK_IFELSE(
+                        [AC_LANG_PROGRAM(
+                            [${myIPHLPAPI_TEST_HEADERS}],
+                            [${myIPHLPAPI_TEST_GAI}])],
+                        [ac_cv_func_GetAdaptersInfo=yes
+                        ], [
+                            NETLIBS_GETADDRS="-liphlpapi"
+                            LIBS="$LIBS $NETLIBS $NETLIBS_GETADDRS"
+                            AX_RUN_OR_LINK_IFELSE(
+                                [AC_LANG_PROGRAM(
+                                    [${myIPHLPAPI_TEST_HEADERS}],
+                                    [${myIPHLPAPI_TEST_GAI}])],
+                                [
+                                    ac_cv_func_GetAdaptersInfo=yes
+                                ], [
+                                    ac_cv_func_GetAdaptersInfo=no
+                                    NETLIBS_GETADDRS=""
+                                ]
+                            )
+                        ]
+                    )
+                    AC_LANG_POP([C])
+                    LIBS="$SAVED_LIBS"
+                ])
+                AS_IF([test x"${ac_cv_func_GetAdaptersInfo}" = xyes],
+                    [AC_DEFINE([HAVE_GETADAPTERSINFO], 1, [defined if system has the GetAdaptersInfo() method])],
+                    [dnl AC_MSG_WARN([WIN32 library routine GetAdaptersInfo() not found])
+                     AS_CASE([${target_os}],
+                         [*mingw*], [AC_MSG_WARN([Windows antivirus might block this test])]
+                         )
+                    ]
+                    )
+
+            ])
+            ]
+    )]
+)
+AC_SUBST([NETLIBS_GETADDRS])
+
+
 dnl ----------------------------------------------------------------------
-dnl Check for python binary program names per language version
+dnl Check for Python binary program names per language version
 dnl to embed into scripts and Make rules
 NUT_CHECK_PYTHON_DEFAULT
 
@@ -1699,6 +2072,59 @@ NUT_ARG_WITH([debuginfo],
     [no])
 dnl To help find warning/error details in a wall of text, see --enable-Wcolor handled above
 
+dnl ----------------------------------------------------------------------
+dnl Check for with-ssl, and --with-nss or --with-openssl which can be used
+dnl by NUT as well as its networking-capable dependencies (net-snmp, etc.)
+dnl Only one can be enabled at a time, with a preference for OpenSSL
+dnl if both are available
+
+nut_ssl_lib=""
+
+NUT_ARG_WITH([ssl], [enable SSL support (either NSS or OpenSSL)], [auto])
+NUT_ARG_WITH([nss], [enable SSL support using Mozilla NSS], [auto])
+NUT_ARG_WITH([openssl], [enable SSL support using OpenSSL], [auto])
+
+dnl ${nut_with_ssl}: any value except "yes" or "no" is treated as "auto".
+if test "${nut_with_ssl}" != "no"; then
+   dnl check if either NSS or OpenSSL was explicitly requested
+   if test "${nut_with_nss}" = "yes"; then
+      NUT_CHECK_LIBNSS
+      if test "${nut_have_libnss}" != "yes"; then
+         AC_MSG_ERROR([Mozilla NSS not found (required for SSL support)])
+      fi
+   elif test "${nut_with_openssl}" = "yes"; then
+      NUT_CHECK_LIBOPENSSL
+      if test "${nut_have_openssl}" != "yes"; then
+         AC_MSG_ERROR([OpenSSL not found (required for SSL support)])
+      fi
+   else
+      dnl Prefer OpenSSL over NSS otherwise
+      NUT_CHECK_LIBOPENSSL
+      if test "${nut_have_openssl}" != "yes"; then
+         NUT_CHECK_LIBNSS
+         if test "${nut_have_libnss}" != "yes"; then
+            dnl Only abort if SSL has been explicitly requested by the user
+            if test "${nut_with_ssl}" = "yes"; then
+               AC_MSG_ERROR([Neither Mozilla NSS nor OpenSSL was found, but one is needed for the requested SSL support.])
+            else
+               AC_MSG_WARN([Neither Mozilla NSS nor OpenSSL was found (required for SSL support)])
+            fi
+            nut_with_ssl="no"
+         else
+            nut_with_nss="${nut_have_libnss}"
+         fi
+      else
+         nut_with_openssl="${nut_have_openssl}"
+      fi
+   fi
+fi
+
+AM_CONDITIONAL(WITH_NSS, test "${nut_with_nss}" = "yes")
+AM_CONDITIONAL(WITH_OPENSSL, test "${nut_with_openssl}" = "yes")
+
+NUT_REPORT_FEATURE([enable SSL support], [${nut_with_ssl}], [${nut_ssl_lib}],
+					[WITH_SSL], [Define to enable SSL])
+
 dnl ----------------------------------------------------------------------
 dnl Check for presence and compiler flags of various libraries
 
@@ -2033,12 +2459,11 @@ if test "${nut_with_linux_i2c}" != no; then
                 [AC_DEFINE([HAVE_LINUX_SMBUS_H], [1],
                     [Define to 1 if you have <i2c/smbus.h>.])]
             )
+            nut_have_linux_i2c="no"
             AC_CHECK_DECLS(
                 [i2c_smbus_access, i2c_smbus_read_byte_data, i2c_smbus_write_byte_data, i2c_smbus_read_word_data, i2c_smbus_write_word_data, i2c_smbus_read_block_data],
-                [], dnl # nut_with_linux_i2c="yes"
-                [AS_IF([test "${nut_with_linux_i2c}" = "yes"],
-                    [AC_MSG_ERROR(i2c was required but can not be fulfilled for this build)],
-                    [nut_with_linux_i2c="no"])],
+                [nut_have_linux_i2c="yes"],
+                [],
                 [#include <stdio.h>
                  #ifdef HAVE_LINUX_I2C_DEV_H
                  #include <linux/i2c-dev.h>
@@ -2054,13 +2479,26 @@ if test "${nut_with_linux_i2c}" != no; then
             dnl Note: here we keep the verdict from above, or make it worse.
             LIBS_SAVED="$LIBS"
             LIBS=""
-            AC_SEARCH_LIBS([i2c_smbus_read_byte, i2c_smbus_access, i2c_smbus_read_byte_data, i2c_smbus_write_byte_datai2c_smbus_write_byte_data, i2c_smbus_read_word_data, i2c_smbus_write_word_data, i2c_smbus_read_block_data],
-                [i2c],
+            AS_IF([test "${nut_have_linux_i2c}" = yes], [
+                nut_have_linux_i2c="no"
+                AC_SEARCH_LIBS(i2c_smbus_read_byte, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_access, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_read_byte_data, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_write_byte_data, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_read_word_data, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_write_word_data, i2c, [
+                AC_SEARCH_LIBS(i2c_smbus_read_block_data, i2c, [
+                    [nut_have_linux_i2c="yes"]
+                ])])])])])])])])
+
+            dnl # Note: *with* (desire) is not "no" in this big if-clause
+            AS_IF([test "${nut_have_linux_i2c}" = yes],
                 [nut_with_linux_i2c="yes"],
                 [AS_IF([test "${nut_with_linux_i2c}" = "yes"],
                     [AC_MSG_ERROR(i2c was required but can not be fulfilled for this build)],
                     [nut_with_linux_i2c="no"])
                 ])
+
             LIBI2C_LIBS="$LIBS"
             LIBS="$LIBS_SAVED"
             ;;
@@ -2080,58 +2518,6 @@ NUT_REPORT_FEATURE(
     [Define to enable I2C support]
 )
 
-dnl ----------------------------------------------------------------------
-dnl Check for with-ssl, and --with-nss or --with-openssl
-dnl Only one can be enabled at a time, with a preference for OpenSSL
-dnl if both are available
-
-nut_ssl_lib=""
-
-NUT_ARG_WITH([ssl], [enable SSL support (either NSS or OpenSSL)], [auto])
-NUT_ARG_WITH([nss], [enable SSL support using Mozilla NSS], [auto])
-NUT_ARG_WITH([openssl], [enable SSL support using OpenSSL], [auto])
-
-dnl ${nut_with_ssl}: any value except "yes" or "no" is treated as "auto".
-if test "${nut_with_ssl}" != "no"; then
-   dnl check if either NSS or OpenSSL was explicitly requested
-   if test "${nut_with_nss}" = "yes"; then
-      NUT_CHECK_LIBNSS
-      if test "${nut_have_libnss}" != "yes"; then
-         AC_MSG_ERROR([Mozilla NSS not found (required for SSL support)])
-      fi
-   elif test "${nut_with_openssl}" = "yes"; then
-      NUT_CHECK_LIBOPENSSL
-      if test "${nut_have_openssl}" != "yes"; then
-         AC_MSG_ERROR([OpenSSL not found (required for SSL support)])
-      fi
-   else
-      dnl Prefer OpenSSL over NSS otherwise
-      NUT_CHECK_LIBOPENSSL
-      if test "${nut_have_openssl}" != "yes"; then
-         NUT_CHECK_LIBNSS
-         if test "${nut_have_libnss}" != "yes"; then
-            dnl Only abort if SSL has been explicitly requested by the user
-            if test "${nut_with_ssl}" = "yes"; then
-               AC_MSG_ERROR([Neither Mozilla NSS nor OpenSSL was found, but one is needed for the requested SSL support.])
-            else
-               AC_MSG_WARN([Neither Mozilla NSS nor OpenSSL was found (required for SSL support)])
-            fi
-            nut_with_ssl="no"
-         else
-            nut_with_nss="${nut_have_libnss}"
-         fi
-      else
-         nut_with_openssl="${nut_have_openssl}"
-      fi
-   fi
-fi
-
-AM_CONDITIONAL(WITH_NSS, test "${nut_with_nss}" = "yes")
-AM_CONDITIONAL(WITH_OPENSSL, test "${nut_with_openssl}" = "yes")
-
-NUT_REPORT_FEATURE([enable SSL support], [${nut_with_ssl}], [${nut_ssl_lib}],
-					[WITH_SSL], [Define to enable SSL])
-
 dnl ----------------------------------------------------------------------
 dnl Check for --with-wrap
 
@@ -2191,6 +2577,8 @@ fi
 NUT_REPORT_FEATURE([enable libltdl (Libtool dlopen abstraction) support], [${nut_with_libltdl}], [],
 					[WITH_LIBLTDL], [Define to enable libltdl (Libtool dlopen abstraction) support])
 
+dnl Explicitly report if we are building nut-scanner or not
+dnl since it requires libltdl
 if test x"${nut_with_libltdl}" = x"no" && test x"${nut_with_nut_scanner}" = x"yes"; then
     AC_MSG_ERROR([libltdl support was disabled or not found, but --with-nut-scanner was requested and requires it])
 fi
@@ -2228,29 +2616,37 @@ NUT_REPORT_FEATURE([build CGI programs], [${nut_with_cgi}], [],
 dnl ----------------------------------------------------------------------
 dnl checks related to --with-pynut and --with-nut_monitor
 
-dnl ${nut_with_nut_monitor}: TODO: arg values to request python 2 gtk2,
-dnl python 3 qt5, or both
-AC_MSG_CHECKING([if we can and should install NUT-Monitor desktop application])
+dnl The PYTHON*_REPORT vars also serve as flags that we have certain usable
+dnl Python interpreter versions to care about below, so we only test for
+dnl their existence once (in NUT_CHECK*PYTHON* m4 macros).
+
+dnl ${nut_with_nut_monitor}: TODO: arg values to request Python 2 gtk2,
+dnl Python 3 qt5, or both
+AC_MSG_CHECKING([if we want install NUT-Monitor desktop application])
+AC_MSG_RESULT([${nut_with_nut_monitor}])
 nut_with_nut_monitor_py2gtk2=""
 nut_with_nut_monitor_py3qt5=""
 nut_with_nut_monitor_desktop=""
 dnl TODO: Add a way to define this path? will have app/ maybe module/ inside...
 nut_with_nut_monitor_dir="${datarootdir}/nut-monitor"
+
 PYTHON_FAILED_TEST_DETAILS=""
+dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-1: ${nut_with_nut_monitor}])
 if test x"${nut_with_nut_monitor}" != xno ; then
     dnl While we might just install for "yes" request, in hopes user would
-    dnl get their python ecosystem in place later, we need some criteria to
+    dnl get their Python ecosystem in place later, we need some criteria to
     dnl avoid installing it always :) Also, need to substitute the shebang.
     if test -z "${PYTHON}${PYTHON2}${PYTHON3}" ; then
         case "${nut_with_nut_monitor}" in
             "auto") nut_with_nut_monitor="no"
-                    PYTHON_FAILED_TEST_DETAILS="No python 2/3 interpreter was found"
+                    PYTHON_FAILED_TEST_DETAILS="No Python 2/3 interpreter was found"
                 ;;
-            "yes")  AC_MSG_ERROR([No python 2/3 interpreter was found, required for NUT-Monitor desktop application])
+            "yes")  AC_MSG_ERROR([No Python 2/3 interpreter was found, required for NUT-Monitor desktop application])
                 ;;
         esac
     fi
 fi
+dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-2: ${nut_with_nut_monitor}])
 
 if test x"${nut_with_nut_monitor}" != xno ; then
     dnl Note: no double-quoting for use, the command string may be multi-token
@@ -2258,53 +2654,73 @@ if test x"${nut_with_nut_monitor}" != xno ; then
     dnl for "config.log" details since... forever? Still, hardcoded numbers...
     PYTHON2_TEST_MODULES="re,glob,codecs,gtk,gtk.glade,gobject,ConfigParser"
     PYTHON3_TEST_MODULES="re,glob,codecs,PyQt5.uic,configparser"
-    if test -n "${PYTHON2}" \
-    && (command -v ${PYTHON2} || which ${PYTHON2}) >/dev/null 2>/dev/null \
-    ; then
+    if test -n "${PYTHON2_VERSION_INFO_REPORT}" ; then
+        AC_MSG_CHECKING([if we have Python2 prerequisites for NUT-Monitor desktop application])
         if ${PYTHON2} -c "import ${PYTHON2_TEST_MODULES}" 1>&5 2>&5 \
         ; then
             nut_with_nut_monitor_py2gtk2="yes"
+            AC_MSG_RESULT([yes])
         else
+            AC_MSG_RESULT([no])
             PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python2 modules: '${PYTHON2_TEST_MODULES}'"
         fi
     fi
 
-    if test -n "${PYTHON3}" \
-    && (command -v ${PYTHON3} || which ${PYTHON3}) >/dev/null 2>/dev/null \
-    ; then
+    if test -n "${PYTHON3_VERSION_INFO_REPORT}" ; then
+        AC_MSG_CHECKING([if we have Python3 prerequisites for NUT-Monitor desktop application])
         if ${PYTHON3} -c "import ${PYTHON3_TEST_MODULES}" 1>&5 2>&5 \
         ; then
             nut_with_nut_monitor_py3qt5="yes"
+            AC_MSG_RESULT([yes])
         else
-            PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python3 modules: '${PYTHON3_TEST_MODULES}'"
+            AC_MSG_RESULT([no])
+            if test -n "${PYTHON_FAILED_TEST_DETAILS}" ; then
+                PYTHON_FAILED_TEST_DETAILS="${PYTHON_FAILED_TEST_DETAILS} and some or all of these Python3 modules: '${PYTHON3_TEST_MODULES}'"
+            else
+                PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python3 modules: '${PYTHON3_TEST_MODULES}'"
+            fi
         fi
     fi
 
     dnl Fall back to default interpreter
     if test -z "${nut_with_nut_monitor_py2gtk2}${nut_with_nut_monitor_py3qt5}" \
-    && test -n "${PYTHON}" \
-    && (command -v ${PYTHON} || which ${PYTHON2}) >/dev/null 2>/dev/null \
+    && test -n "${PYTHON_VERSION_INFO_REPORT}" \
+    && test x"${PYTHON_VERSION_INFO_REPORT}" != x"${PYTHON3_VERSION_INFO_REPORT}" \
+    && test x"${PYTHON_VERSION_INFO_REPORT}" != x"${PYTHON2_VERSION_INFO_REPORT}" \
     ; then
+        AC_MSG_CHECKING([if we have Python3 prerequisites for NUT-Monitor desktop application in default Python])
         if ${PYTHON} -c "import ${PYTHON3_TEST_MODULES}" 1>&5 2>&5 \
         ; then
             nut_with_nut_monitor_py3qt5="yes"
+            AC_MSG_RESULT([yes])
         else
-            PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python3 modules: '${PYTHON3_TEST_MODULES}'"
+            AC_MSG_RESULT([no])
+            if test -n "${PYTHON_FAILED_TEST_DETAILS}" ; then
+                PYTHON_FAILED_TEST_DETAILS="${PYTHON_FAILED_TEST_DETAILS} and some or all of these Python3 modules in default Python: '${PYTHON3_TEST_MODULES}'"
+            else
+                PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python3 modules in default Python: '${PYTHON3_TEST_MODULES}'"
+            fi
         fi
 
+        AC_MSG_CHECKING([if we have Python2 prerequisites for NUT-Monitor desktop application in default Python])
         if ${PYTHON} -c "import ${PYTHON2_TEST_MODULES}" 1>&5 2>&5 \
         ; then
             nut_with_nut_monitor_py2gtk2="yes"
             PYTHON_FAILED_TEST_DETAILS=""
+            AC_MSG_RESULT([yes])
         else
+            AC_MSG_RESULT([no])
             if test -n "${PYTHON_FAILED_TEST_DETAILS}" ; then
-                PYTHON_FAILED_TEST_DETAILS="${PYTHON_FAILED_TEST_DETAILS} and some or all of these Python2 modules: '${PYTHON2_TEST_MODULES}'"
+                PYTHON_FAILED_TEST_DETAILS="${PYTHON_FAILED_TEST_DETAILS} and some or all of these Python2 modules in default Python: '${PYTHON2_TEST_MODULES}'"
             else
-                PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python2 modules: '${PYTHON2_TEST_MODULES}'"
+                PYTHON_FAILED_TEST_DETAILS="Missing some or all of these Python2 modules in default Python: '${PYTHON2_TEST_MODULES}'"
             fi
         fi
     fi
 
+    dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-3: ${nut_with_nut_monitor}])
+    dnl ### AC_MSG_NOTICE([nut_with_nut_monitor_py2gtk2: ${nut_with_nut_monitor_py2gtk2}])
+    dnl ### AC_MSG_NOTICE([nut_with_nut_monitor_py3qt5: ${nut_with_nut_monitor_py3qt5}])
     dnl Can we satisfy any NUT-Monitor installation request?
     if test -n "${nut_with_nut_monitor_py2gtk2}${nut_with_nut_monitor_py3qt5}" ; then
         case "${nut_with_nut_monitor}" in
@@ -2314,11 +2730,14 @@ if test x"${nut_with_nut_monitor}" != xno ; then
         case "${nut_with_nut_monitor}" in
             "auto") nut_with_nut_monitor="no" ;;
             "yes")
-                AC_MSG_ERROR([No python 2/3 interpreter with needed modules was found, as required for NUT-Monitor desktop application: ${PYTHON_FAILED_TEST_DETAILS}])
+                AC_MSG_ERROR([No Python 2/3 interpreter with needed modules was found, as required for NUT-Monitor desktop application: ${PYTHON_FAILED_TEST_DETAILS}])
                 ;;
         esac
     fi
 fi
+
+AC_MSG_CHECKING([if we can and should install NUT-Monitor desktop application])
+dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-4: ${nut_with_nut_monitor}])
 case "${nut_with_nut_monitor}" in
     "no") if test -n "${PYTHON_FAILED_TEST_DETAILS}" ; then
             AC_MSG_RESULT([${nut_with_nut_monitor}: ${PYTHON_FAILED_TEST_DETAILS}])
@@ -2329,6 +2748,7 @@ case "${nut_with_nut_monitor}" in
     *) AC_MSG_RESULT([${nut_with_nut_monitor}]) ;;
 esac
 
+dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-5: ${nut_with_nut_monitor}])
 if test x"${nut_with_nut_monitor}" != xno ; then
     if (command -v desktop-file-install || which desktop-file-install) >/dev/null 2>/dev/null ; then
         case "${nut_with_nut_monitor}" in
@@ -2343,45 +2763,99 @@ if test x"${nut_with_nut_monitor}" != xno ; then
         esac
     fi
 fi
+dnl ### AC_MSG_NOTICE([nut_with_nut_monitor-6: ${nut_with_nut_monitor}])
 
-dnl ${nut_with_pynut}: TODO: arg values to request python 2, 3 or both
-AC_MSG_CHECKING([if we can and should install PyNUT module])
-nut_with_pynut_py=""
-nut_with_pynut_py2=""
-nut_with_pynut_py3=""
+dnl Check if we can use distributed or fallback telnetlib module for PyNUTClient
+nut_have_telnetlib_py=""
+nut_have_telnetlib_py2=""
+nut_have_telnetlib_py3=""
 if test x"${nut_with_pynut}" != xno \
     -a -n "${PYTHON}${PYTHON2}${PYTHON3}" \
 ; then
-    if test -n "${PYTHON2}" \
-    && (command -v ${PYTHON2} || which ${PYTHON2}) >/dev/null 2>/dev/null \
-    ; then
+    if test -n "${PYTHON2_VERSION_INFO_REPORT}" ; then
+        AC_MSG_CHECKING([if we can use stock Python2 telnetlib module provided with interpreter ${PYTHON2}])
         if ${PYTHON2} -c "import telnetlib" \
         ; then
-            nut_with_pynut_py2="yes"
+            nut_have_telnetlib_py2="yes"
+        else
+            nut_have_telnetlib_py2="no"
         fi
+        AC_MSG_RESULT([${nut_have_telnetlib_py2}])
     fi
 
-    if test -n "${PYTHON3}" \
-    && (command -v ${PYTHON3} || which ${PYTHON3}) >/dev/null 2>/dev/null \
-    ; then
+    if test -n "${PYTHON3_VERSION_INFO_REPORT}" ; then
+        AC_MSG_CHECKING([if we can use stock Python3 telnetlib module for PyNUTClient provided with interpreter ${PYTHON3} (note for warnings from Python 3.11 and beyond: we have a fallback nut_telnetlib module just in case)])
         if ${PYTHON3} -c "import telnetlib" \
         ; then
-            nut_with_pynut_py3="yes"
+            nut_have_telnetlib_py3="yes"
+        else
+            nut_have_telnetlib_py3="no"
+        fi
+        AC_MSG_RESULT([${nut_have_telnetlib_py3}])
+
+        if test x"${nut_have_telnetlib_py3}" = x"no" ; then
+            dnl We have a stashed copy from Python 3.10, so
+            dnl this line essentially checks for presence of
+            dnl a usable interpreter implementation compatible
+            dnl with Python 3.x syntax.
+            AC_MSG_CHECKING([if we can use fallback Python3 nut_telnetlib module for PyNUTClient])
+            if (cd "${srcdir}"/scripts/python/module && ${PYTHON3} -c "import nut_telnetlib as telnetlib") \
+            ; then
+                nut_have_telnetlib_py3="yes"
+            fi
+            AC_MSG_RESULT([${nut_have_telnetlib_py3}])
         fi
     fi
 
     dnl Test same-ness of pythons with sys.version also?
-    if test -n "${PYTHON}" \
-    && (command -v ${PYTHON} || which ${PYTHON}) >/dev/null 2>/dev/null \
-    && test "${PYTHON}" != "${PYTHON2}" -a "${PYTHON}" != "${PYTHON3}" \
+    if test -n "${PYTHON_VERSION_INFO_REPORT}" \
+    && test x"${PYTHON_VERSION_INFO_REPORT}" != x"${PYTHON3_VERSION_INFO_REPORT}" \
+    && test x"${PYTHON_VERSION_INFO_REPORT}" != x"${PYTHON2_VERSION_INFO_REPORT}" \
     ; then
+        AC_MSG_CHECKING([if we can use stock Python telnetlib module for PyNUTClient provided with interpreter ${PYTHON} (note for warnings from Python 3.11 and beyond: we have a fallback nut_telnetlib module just in case)])
         if ${PYTHON} -c "import telnetlib" \
         ; then
-            nut_with_pynut_py="yes"
+            nut_have_telnetlib_py="yes"
+        else
+            nut_have_telnetlib_py="no"
+        fi
+        AC_MSG_RESULT([${nut_have_telnetlib_py}])
+
+        if test x"${nut_have_telnetlib_py}" = x"no" ; then
+            dnl See comments above
+            AC_MSG_CHECKING([if we can use fallback Python nut_telnetlib module for PyNUTClient])
+            if (cd "${srcdir}"/scripts/python/module && ${PYTHON} -c "import nut_telnetlib as telnetlib") \
+            ; then
+                nut_have_telnetlib_py="yes"
+            fi
+            AC_MSG_RESULT([${nut_have_telnetlib_py}])
         fi
     fi
 fi
 
+dnl ${nut_with_pynut}: TODO: arg values to request Python 2, 3 or both
+dnl Note that per block above, nut_have_telnetlib_py* values are definitive
+dnl if checked, or empty if skipped (no such Python, not nut_with_pynut, etc.)
+AC_MSG_CHECKING([if we can and should install PyNUT module])
+nut_with_pynut_py=""
+nut_with_pynut_py2=""
+nut_with_pynut_py3=""
+if test x"${nut_with_pynut}" != xno \
+    -a -n "${PYTHON}${PYTHON2}${PYTHON3}" \
+; then
+    if test x"${nut_have_telnetlib_py2}" = x"yes" ; then
+        nut_with_pynut_py2="yes"
+    fi
+
+    if test x"${nut_have_telnetlib_py3}" = x"yes" ; then
+        nut_with_pynut_py3="yes"
+    fi
+
+    if test x"${nut_have_telnetlib_py}" = x"yes" ; then
+        nut_with_pynut_py="yes"
+    fi
+fi
+
 if test -z "${nut_with_pynut_py}${nut_with_pynut_py2}${nut_with_pynut_py3}" ; then
     dnl Not all prereqs are available...
     case "${nut_with_pynut}" in
@@ -2420,7 +2894,7 @@ if test x"${nut_with_pynut}" != xno ; then
                 if test "${nut_with_nut_monitor}" = yes -o "${nut_with_nut_monitor}" = force ; then
                     nut_with_pynut="app"
                 else
-                    AC_MSG_ERROR([python interpreter and/or its site-packages location not found, but required for PyNUT])
+                    AC_MSG_ERROR([Python interpreter and/or its site-packages location not found, but required for PyNUT])
                 fi
                 ;;
         esac
@@ -2471,6 +2945,18 @@ AC_SUBST([nut_with_pynut_py], [${nut_with_pynut_py}])
 AC_SUBST([nut_with_pynut_py2], [${nut_with_pynut_py2}])
 AC_SUBST([nut_with_pynut_py3], [${nut_with_pynut_py3}])
 
+dnl MacOS Darwin has a problem with script shebangs, and tends to run anything
+dnl with shell. On the upside, it has no limit on length or amount of tokens
+dnl in the shebang line.
+dnl https://github.com/NixOS/nixpkgs/issues/65351/
+AS_CASE([${target_os}],
+	[*darwin*], [
+		AS_IF([test -n "${PYTHON}"  -a x"${PYTHON}"  != xno], [ PYTHON=" /usr/bin/env ${PYTHON}"])
+		AS_IF([test -n "${PYTHON2}" -a x"${PYTHON2}" != xno], [PYTHON2=" /usr/bin/env ${PYTHON2}"])
+		AS_IF([test -n "${PYTHON3}" -a x"${PYTHON3}" != xno], [PYTHON3=" /usr/bin/env ${PYTHON3}"])
+		]
+)
+
 AS_IF([test "${nut_with_nut_monitor}" != no -o "${nut_with_pynut}" != no], [
     NUT_REPORT([use default  Python  interpreter],   [${PYTHON}])
     NUT_REPORT([use specific Python2 interpreter],   [${PYTHON2}])
@@ -2586,6 +3072,9 @@ case "${nut_with_doc}" in
 	skip|all=skip)
 		nut_doc_build_list="man=skip html-single=skip html-chunked=skip pdf=skip"
 		;;
+	dist-auto) # Experimental, currently only for MANs: prefer disted files if present, auto otherwise
+		nut_doc_build_list="man=dist-auto html-single=dist-auto html-chunked=dist-auto pdf=dist-auto"
+		;;
 	no|all=no)
 		nut_doc_build_list=""
 		;;
@@ -2626,7 +3115,7 @@ for nut_doc_build_target in $nut_doc_build_list; do
 		;;
 	esac
 	case "${nut_doc_build_target_flag}" in
-	yes|no|auto|skip) ;;
+	yes|no|auto|skip|dist-auto) ;;
 	"") nut_doc_build_target_flag="yes" ;;
 	*)	rm -rf "${DOCTESTDIR}"
 		AC_MSG_ERROR([Invalid documentation format option: ${nut_doc_build_target}]) ;;
@@ -2693,6 +3182,7 @@ dnl not fail if we have no tools to generate it (so add to SKIP list).
 	pdf*)
 		AC_MSG_CHECKING([if dblatex version can build ${nut_doc_build_target_base} (minimum required ${DBLATEX_MIN_VERSION})])
 		can_build_doc_pdf=no
+		can_build_doc_pdf_nonascii_titles=no
 		AX_COMPARE_VERSION([${DBLATEX_VERSION}], [ge], [${DBLATEX_MIN_VERSION}], [
 			( cd "$DOCTESTDIR" && ${A2X} --format=pdf --destination-dir=. "${abs_srcdir}"/docs/asciidoc.txt && test -s asciidoc.pdf ) && can_build_doc_pdf=yes
 			rm -f "${DOCTESTDIR}"/asciidoc.pdf
@@ -2700,6 +3190,10 @@ dnl not fail if we have no tools to generate it (so add to SKIP list).
 		if test "${can_build_doc_pdf}" = yes ; then
 			AC_MSG_RESULT(yes)
 			DOC_BUILD_LIST="${DOC_BUILD_LIST} ${nut_doc_build_target_base}"
+			AC_MSG_CHECKING([if dblatex can process non-ASCII section titles for PDF])
+			( cd "$DOCTESTDIR" && sed -e 's/^Intro/'"`printf '\303\215'`"'ntro/' -e 's/Works in Progress/Works '"`printf '\303\255'`"'n Progress/' < "${abs_srcdir}"/docs/asciidoc.txt > asciidoc.tmp.txt && ${A2X} --format=pdf --destination-dir=. asciidoc.tmp.txt && test -s asciidoc.tmp.pdf ) && can_build_doc_pdf_nonascii_titles=yes
+			rm -f "${DOCTESTDIR}"/asciidoc.tmp.pdf
+			AC_MSG_RESULT(${can_build_doc_pdf_nonascii_titles})
 		else
 			AC_MSG_RESULT(no)
 			if test "${nut_doc_build_target_flag}" = "yes" ; then
@@ -2712,31 +3206,48 @@ dnl not fail if we have no tools to generate it (so add to SKIP list).
 		;;
 
 	man*)
+		dnl Experimental support for --with-doc=man=dist-auto to prefer pre-disted docs if available, below
 		AC_MSG_CHECKING([if we can build ${nut_doc_build_target_base}])
 		can_build_doc_man=no
+		have_disted_doc_man=no
+		want_disted_doc_man=no
+		if test -s "${abs_srcdir}"/docs/man/snmp-ups.8 ; then
+			dnl Test that groff files exist (building from distributed tarball, not git repo)
+			have_disted_doc_man=yes
+		fi
+		if test x"${nut_doc_build_target}" = x"man=dist-auto" || test "${nut_doc_build_target_flag}" = "dist-auto"; then
+			want_disted_doc_man=yes
+		fi
 		if test "${nut_have_asciidoc}" = yes ; then
 			( cd "$DOCTESTDIR" && ${A2X} --format manpage --destination-dir=. --xsltproc-opts="--nonet" "${abs_srcdir}"/docs/man/snmp-ups.txt && test -s snmp-ups.8 ) && can_build_doc_man=yes
 			rm -f "${DOCTESTDIR}"/snmp-ups.8
 		fi
-		if test "${can_build_doc_man}" = yes ; then
-			AC_MSG_RESULT(yes)
-			DOC_BUILD_LIST="${DOC_BUILD_LIST} ${nut_doc_build_target_base}"
+		if test "${want_disted_doc_man}" = yes && test "${have_disted_doc_man}" = yes ; then
+			AC_MSG_NOTICE([Requested, and can, install pre-built distributed copies of ${nut_doc_build_target_base} documentation])
+			DOC_SKIPBUILD_LIST="${DOC_SKIPBUILD_LIST} ${nut_doc_build_target_base}"
+			DOC_INSTALL_DISTED_MANS="yes"
+			dnl Avoid rebuilding existing build products due to their timestamp dependencies:
+			touch -r "${abs_srcdir}"/docs/man/Makefile.am "${abs_srcdir}"/docs/man/*.{1,2,3,4,5,6,7,8,9}* "${abs_srcdir}"/docs/man/*.{txt,xml,html,pdf} || true
 		else
-			AC_MSG_RESULT(no)
-			if test "${nut_doc_build_target_flag}" = "yes" ; then
-				DOC_CANNOTBUILD_LIST="${DOC_CANNOTBUILD_LIST} ${nut_doc_build_target_base}"
-				AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation which you requested])
+			if test "${can_build_doc_man}" = yes ; then
+				AC_MSG_RESULT(yes)
+				DOC_BUILD_LIST="${DOC_BUILD_LIST} ${nut_doc_build_target_base}"
 			else
-				DOC_SKIPBUILD_LIST="${DOC_SKIPBUILD_LIST} ${nut_doc_build_target_base}"
-				if test "${nut_doc_build_target_flag}" = "auto" ; then
-dnl Test that groff files exist (building from distributed tarball, not git repo)
-					if test -s "${abs_srcdir}"/docs/man/snmp-ups.8 ; then
-						AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation, but can install pre-built distributed copies])
-						DOC_INSTALL_DISTED_MANS="yes"
-					else
-						AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation, and unable to install pre-built distributed copies because they are absent])
-					fi
-				fi  # Other variants include "no", "skip"...
+				AC_MSG_RESULT(no)
+				if test "${nut_doc_build_target_flag}" = "yes" ; then
+					DOC_CANNOTBUILD_LIST="${DOC_CANNOTBUILD_LIST} ${nut_doc_build_target_base}"
+					AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation which you requested])
+				else
+					DOC_SKIPBUILD_LIST="${DOC_SKIPBUILD_LIST} ${nut_doc_build_target_base}"
+					if test "${nut_doc_build_target_flag}" = "auto" || test "${nut_doc_build_target_flag}" = "dist-auto" ; then
+						if test "${have_disted_doc_man}" = yes ; then
+							AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation, but can install pre-built distributed copies])
+							DOC_INSTALL_DISTED_MANS="yes"
+						else
+							AC_MSG_WARN([Unable to build ${nut_doc_build_target_base} documentation, and unable to install pre-built distributed copies because they are absent])
+						fi
+					fi  # Other variants include "no", "skip"...
+				fi
 			fi
 		fi
 		;;
@@ -2775,6 +3286,8 @@ no)
 	;;
 esac
 
+AM_CONDITIONAL(WITH_PDF_NONASCII_TITLES, [test x"$can_build_doc_pdf_nonascii_titles" = xyes])
+
 NUT_REPORT_FEATURE([build specific documentation format(s)], [${nut_with_doc}], [${DOC_BUILD_LIST}],
 					[WITH_DOCS], [Define to enable overall documentation generation])
 
@@ -2782,9 +3295,9 @@ NUT_REPORT_FEATURE([build specific documentation format(s)], [${nut_with_doc}],
 # for "make check" in "docs/" here...
 DOC_CHECK_LIST=""
 if test "${nut_with_doc}" = yes ; then
-    for V in $DOC_BUILD_LIST ; do
-        DOC_CHECK_LIST="$DOC_CHECK_LIST check-$V"
-    done
+	for V in $DOC_BUILD_LIST ; do
+		DOC_CHECK_LIST="$DOC_CHECK_LIST check-$V"
+	done
 fi
 
 WITH_MANS=no
@@ -2804,6 +3317,39 @@ AM_CONDITIONAL(WITH_MANS, test "${WITH_MANS}" = "yes")
 AM_CONDITIONAL(SKIP_MANS, test "${SKIP_MANS}" = "yes")
 AM_CONDITIONAL(DOC_INSTALL_DISTED_MANS, test "${DOC_INSTALL_DISTED_MANS}" = "yes")
 
+WITH_HTML_SINGLE=no
+SKIP_HTML_SINGLE=no
+if echo "${DOC_BUILD_LIST}" | grep -w "html-single" >/dev/null ; then
+	WITH_HTML_SINGLE=yes
+fi
+if echo "${DOC_SKIPBUILD_LIST}" | grep -w "html-single" >/dev/null ; then
+	SKIP_HTML_SINGLE=yes
+fi
+AM_CONDITIONAL(WITH_HTML_SINGLE, test "${WITH_HTML_SINGLE}" = "yes")
+AM_CONDITIONAL(SKIP_HTML_SINGLE, test "${SKIP_HTML_SINGLE}" = "yes")
+
+WITH_HTML_CHUNKED=no
+SKIP_HTML_CHUNKED=no
+if echo "${DOC_BUILD_LIST}" | grep -w "html-chunked" >/dev/null ; then
+	WITH_HTML_CHUNKED=yes
+fi
+if echo "${DOC_SKIPBUILD_LIST}" | grep -w "html-chunked" >/dev/null ; then
+	SKIP_HTML_CHUNKED=yes
+fi
+AM_CONDITIONAL(WITH_HTML_CHUNKED, test "${WITH_HTML_CHUNKED}" = "yes")
+AM_CONDITIONAL(SKIP_HTML_CHUNKED, test "${SKIP_HTML_CHUNKED}" = "yes")
+
+WITH_PDFS=no
+SKIP_PDFS=no
+if echo "${DOC_BUILD_LIST}" | grep -w "pdf" >/dev/null ; then
+	WITH_PDFS=yes
+fi
+if echo "${DOC_SKIPBUILD_LIST}" | grep -w "pdf" >/dev/null ; then
+	SKIP_PDFS=yes
+fi
+AM_CONDITIONAL(WITH_PDFS, test "${WITH_PDFS}" = "yes")
+AM_CONDITIONAL(SKIP_PDFS, test "${SKIP_PDFS}" = "yes")
+
 dnl ----------------------------------------------------------------------
 dnl checks related to --with-dev
 
@@ -3276,8 +3822,8 @@ if test x"$solarissmf" = xauto ; then
 	fi
 fi
 AC_MSG_RESULT([${solarissmf}])
-AM_CONDITIONAL(WITH_SOLARIS_SMF, test x"$solarissmf" = x"yes")
-NUT_REPORT([consider basic SMF support], [${solarissmf}])
+NUT_REPORT_FEATURE([consider basic SMF support], [${solarissmf}], [],
+					[WITH_SOLARIS_SMF], [Define to consider basic SMF support (provide units and configuration files)])
 
 
 AC_MSG_CHECKING(whether to install Solaris SVR4 (legacy) init-script files)
@@ -3547,6 +4093,10 @@ AS_IF([test x"${with_libsystemd}" = xyes && test x"${SYSTEMD_SUPPORTS_DAEMON_TYP
 NUT_REPORT_FEATURE([build with tighter systemd support], [${with_libsystemd}], [],
 	[WITH_LIBSYSTEMD], [Define to build with tighter systemd support (sd_notify etc)])
 
+nut_with_libsystemd_inhibitor=0
+AS_IF([test x"${with_libsystemd}" = xyes && test x"${nut_have_libsystemd_inhibitor}" = xyes], [nut_with_libsystemd_inhibitor=1])
+AC_DEFINE_UNQUOTED(WITH_LIBSYSTEMD_INHIBITOR, [${nut_with_libsystemd_inhibitor}], [Define as 1 if we can use systemd inhibitor interface here])
+AM_CONDITIONAL([WITH_LIBSYSTEMD_INHIBITOR], [test x"${nut_with_libsystemd_inhibitor}" = x1])
 
 dnl
 dnl Tests for CppUnit availability and usability (will be built if we can,
@@ -3769,6 +4319,12 @@ else
 fi
 AM_CONDITIONAL(WITH_AUGLENS, test -n "${auglensdir}")
 
+if test -n "${auglensdir}"; then
+	auglenstestsdir="${auglensdir}/tests"
+else
+	auglenstestsdir=''
+fi
+
 AC_PATH_PROGS([AUGPARSE], [augparse], [none])
 AM_CONDITIONAL([HAVE_AUGPARSE], [test "x${AUGPARSE}" != "xnone"])
 AC_MSG_CHECKING([whether to enable Augeas configuration-management lenses tests])
@@ -3778,6 +4334,7 @@ else
 	AC_MSG_RESULT(no)
 fi
 
+dnl ----------------------------------------------------------------------
 
 AC_MSG_CHECKING(whether to install hotplug rules)
 AC_ARG_WITH(hotplug-dir,
@@ -4202,6 +4759,8 @@ AC_SUBST(TREE_VERSION)
 AC_SUBST(NUT_NETVERSION)
 AC_SUBST(FORCE_NUT_VERSION)
 AC_SUBST(NUT_SOURCE_GITREV)
+AC_SUBST(NUT_SOURCE_GITREV_IS_RELEASE)
+AC_SUBST(NUT_SOURCE_GITREV_SEMVER)
 AC_SUBST(NUT_SOURCE_GITREV_NUMERIC)
 AC_SUBST(LIBSSL_CFLAGS)
 AC_SUBST(LIBSSL_LIBS)
@@ -4251,6 +4810,7 @@ AC_SUBST(DRIVER_BUILD_LIST)
 AC_SUBST(DRIVER_MAN_LIST)
 AC_SUBST(DRIVER_MAN_LIST_PAGES)
 AC_SUBST(DRIVER_INSTALL_TARGET)
+AC_SUBST(BSDKVMPROCLIBS)
 AC_SUBST(NETLIBS)
 AC_SUBST(SERLIBS)
 AC_SUBST(SEMLIBS)
@@ -4278,11 +4838,14 @@ AC_SUBST(devddir)
 AC_SUBST(driverexecdir)
 AC_SUBST(freebsdquirksdir)
 AC_SUBST(htmldir)
+AC_SUBST(htmldocdir)
+AC_SUBST(htmlmandir)
 AC_SUBST(pkgconfigdir)
 AC_SUBST(systemdsystemunitdir)
 AC_SUBST(systemdshutdowndir)
 AC_SUBST(systemdtmpfilesdir)
 AC_SUBST(auglensdir)
+AC_SUBST(auglenstestsdir)
 AC_SUBST(hotplugdir)
 AC_SUBST(udevdir)
 
@@ -4641,19 +5204,23 @@ dnl When building ON Windows (mingw/MSYS2, cygwin, etc.) fudge these
 dnl path strings back to what native OS methods would recognize.
 AS_CASE([${target_os}],
     [*mingw*], [
+        AC_MSG_NOTICE([Will try to resolve Windows paths to ABS_TOP_SRCDIR and ABS_TOP_BUILDDIR with cygpath or mingw/msys pwd -W tool (would fail if not a native build)])
+
         dnl Cygwin path resolver
         AC_CHECK_TOOL([CYGPATH], [cygpath], [none])
-        AS_IF([test "x${CYGPATH}" != "xnone"], [
+        AS_IF([test "x${CYGPATH}" != "xnone" && test x"`${CYGPATH}`" != x], [
             tmp="`${CYGPATH} -m "${ABS_TOP_BUILDDIR}" | sed -e 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_BUILDDIR="$tmp"
             tmp="`${CYGPATH} -m "${ABS_TOP_SRCDIR}" | sed 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_SRCDIR="$tmp"
         ],[
             dnl MSYS pwd with -W option to resolve
-            AC_CHECK_TOOL([PWD], [pwd], [none])
-            AS_IF([test "x${PWD}" != "xnone"], [
-                tmp="`(cd "${ABS_TOP_BUILDDIR}" && ${PWD} -W) | sed 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_BUILDDIR="$tmp"
-                tmp="`(cd "${ABS_TOP_SRCDIR}" && ${PWD} -W) | sed 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_SRCDIR="$tmp"
+            AC_CHECK_TOOL([PWDTOOL], [pwd], [none])
+            AS_IF([test "x${PWDTOOL}" != "xnone" && test x"`${PWDTOOL} -W`" != x], [
+                tmp="`(cd "${ABS_TOP_BUILDDIR}" && ${PWDTOOL} -W) | sed 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_BUILDDIR="$tmp"
+                tmp="`(cd "${ABS_TOP_SRCDIR}" && ${PWDTOOL} -W) | sed 's,/,\\\\\\\\,g'`" && test -n "$tmp" && test -d "$tmp" && ABS_TOP_SRCDIR="$tmp"
             ])
         ])
+
+        AC_MSG_NOTICE([FWIW, assuming ABS_TOP_SRCDIR="$ABS_TOP_SRCDIR" and ABS_TOP_BUILDDIR="$ABS_TOP_BUILDDIR"])
 ])
 
 dnl Use these at best for tests (e.g. nutconf), not production code:
@@ -4755,6 +5322,19 @@ AC_ARG_VAR(CCACHE_BASEDIR)
 AC_ARG_VAR(CCACHE_DIR)
 AC_ARG_VAR(CCACHE_PATH)
 
+dnl Some versions of ccache take poorly to an exported empty CCACHE_DIR etc.
+dnl Avoid exporting them if not set at the configure time (assuming ci_build.sh
+dnl integration or user's shell profile sets them persistently)
+AS_IF([test x"${CCACHE_NAMESPACE-}" = x], [NUT_AM_EXPORT_CCACHE_NAMESPACE="#"], [NUT_AM_EXPORT_CCACHE_NAMESPACE=""])
+AC_SUBST(NUT_AM_EXPORT_CCACHE_NAMESPACE)
+AS_IF([test x"${CCACHE_BASEDIR-}" = x], [NUT_AM_EXPORT_CCACHE_BASEDIR="#"], [NUT_AM_EXPORT_CCACHE_BASEDIR=""])
+AC_SUBST(NUT_AM_EXPORT_CCACHE_BASEDIR)
+AS_IF([test x"${CCACHE_DIR-}" = x], [NUT_AM_EXPORT_CCACHE_DIR="#"], [NUT_AM_EXPORT_CCACHE_DIR=""])
+AC_SUBST(NUT_AM_EXPORT_CCACHE_DIR)
+
+dnl Application of PATH_DURING_CONFIGURE is also fenced by NUT_AM_EXPORT_CCACHE_PATH:
+AS_IF([test x"${CCACHE_PATH-}" = x], [NUT_AM_EXPORT_CCACHE_PATH="#"], [NUT_AM_EXPORT_CCACHE_PATH=""])
+AC_SUBST(NUT_AM_EXPORT_CCACHE_PATH)
 PATH_DURING_CONFIGURE="$PATH"
 AC_SUBST(PATH_DURING_CONFIGURE)
 
@@ -4789,7 +5369,16 @@ AS_CASE(["${CONFIG_CXXFLAGS}"],
 AS_CASE(["${nut_with_debuginfo_C}"],
     [yes], [
         AS_IF([test x"${CLANGCC}" = x"yes" -o x"${GCC}" = x"yes"], [
-            CFLAGS="${CFLAGS} -O0 -g3 -gdwarf-2"
+            dnl Where we can enable debug, minimize the optimizations.
+            dnl On some platforms LIBNETSNMP_CFLAGS or some such defines
+            dnl _FORTIFY_SOURCE=N which in turn "requires compiling with
+            dnl optimization", so we can not disable it in CFLAGS applied
+            dnl in the end of each and every build command line (highest
+            dnl priority). However, CPPFLAGS are before (making these
+            dnl lines an implementation-dependent hack)...
+            dnl AS_IF([set | grep -E 'FORTIFY_SOURCE'], [], [CFLAGS="${CFLAGS} -O0"])
+            CPPFLAGS="${CPPFLAGS} -O0"
+            CFLAGS="${CFLAGS} -g3 -gdwarf-2"
             ],[nut_with_debuginfo_C="Unknown C compiler, not adding options"]
         )],
     dnl # [no]: By default we do not add debug info
@@ -4802,7 +5391,9 @@ AS_CASE(["${nut_with_debuginfo_C}"],
 AS_CASE(["${nut_with_debuginfo_CXX}"],
     [yes], [
         AS_IF([test "x$CLANGXX" = xyes -o "x$GXX" = xyes], [
-            dnl Where we can enable debug, minimize the optimizations
+            dnl Where we can enable debug, minimize the optimizations.
+            dnl NOTE: Concerns for -O0 behavior commented above are about C code,
+            dnl not seen (yet) with C++.
             CXXFLAGS="${CXXFLAGS} -O0 -g3 -gdwarf-2"
             dnl Use same settings for CPPUNIT tests (they bump their own by default)
             CPPUNIT_NUT_CXXFLAGS=""
diff --git a/data/Makefile.am b/data/Makefile.am
index 5fba2e442b..29c440bac2 100644
--- a/data/Makefile.am
+++ b/data/Makefile.am
@@ -9,7 +9,7 @@ EXTRA_DIST = evolution500.seq epdu-managed.dev
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/data/cmdvartab b/data/cmdvartab
index 9a1d9ab3a9..38d2b356dd 100644
--- a/data/cmdvartab
+++ b/data/cmdvartab
@@ -194,6 +194,7 @@ VARDESC driver.version.usb "USB library version"
 # VARDESC driver.parameter.[[:alpha:]]+ "Driver parameter: <name>"
 # VARDESC driver.flag.[[:alpha:]]+ "Driver flag: <name>"
 
+CMDDESC driver.exit "Tell the driver daemon to just exit its program (so the caller or service management framework can restart it with new options)"
 CMDDESC driver.killpower "Tell the driver daemon to initiate UPS shutdown; should be unlocked with driver.flag.allow_killpower option or variable setting"
 CMDDESC driver.reload "Reload running driver configuration from the file system (only works for changes in some options)"
 CMDDESC driver.reload-or-error "Reload running driver configuration from the file system (only works for changes in some options); return an error if something changed and could not be applied live (so the caller can restart it with new options)"
diff --git a/data/driver.list.in b/data/driver.list.in
index 32b795cb2e..7ed01d0987 100644
--- a/data/driver.list.in
+++ b/data/driver.list.in
@@ -34,6 +34,8 @@
 #
 # Duplicate text in the last field will be cooked out during the conversion
 # to HTML with ROWSPAN magic.  They must be an exact match for this to work.
+#
+# The entry may be followed by comments. Be sure to not use double-quotes there!
 
 "Ablerex"	"ups"	"2"	"625L"	"USB"	"blazer_usb"
 "Ablerex"	"ups"	"2"	"Hope Office 400/600"	""	"blazer_ser"
@@ -77,6 +79,7 @@
 "APC"	"ups"	"3"	"Back-UPS BF500"	"USB"	"usbhid-ups"
 "APC"	"ups"	"3"	"BACK-UPS XS LCD"	"USB"	"usbhid-ups"
 "APC"	"ups"	"3"	"Back-UPS XS 1000M (Back-UPS Pro 1000, Model BX1000M)"	"USB"	"usbhid-ups"	# https://github.com/networkupstools/nut/issues/139
+"APC"	"ups"	"3"	"Back-UPS BX****MI Series (may need tweaks since 2023)"	"USB"	"usbhid-ups lbrb_log_delay_sec=N lbrb_log_delay_without_calibrating onlinedischarge_calibration"	# https://github.com/networkupstools/nut/issues/2347
 "APC"	"ups"	"3"	"SMC2200BI-BR"	"USB"	"usbhid-ups"	# https://github.com/networkupstools/nut/issues/557
 "APC"	"ups"	"3"	"Smart-UPS (USB)"	"USB"	"usbhid-ups"
 "APC"	"ups"	"3"	"Smart-UPS 750 (SMT750I, USB)"	"USB"	"usbhid-ups"
@@ -194,6 +197,11 @@
 "Best Power"	"ups"	"1"	"Micro-Ferrups"	""	"bestuferrups"
 "Best Power"	"ups"	"1"	"Fortress/Ferrups"	"f-command support"	"bestfcom"
 
+"Bicker"	"ups"	"3"	"UPSIC-1205"	""	"bicker_ser"
+"Bicker"	"ups"	"3"	"UPSIC-2403"	""	"bicker_ser"
+"Bicker"	"ups"	"3"	"DC2412-UPS"	""	"bicker_ser"
+"Bicker"	"ups"	"3"	"DC2412-UPS-LD"	""	"bicker_ser"
+
 "Borri"	"ups"	"2"	"B400-010-B/B400-020-B/B400-030-B/B400-010-C/B400-020-C/B400-030-C"	"USB"	"blazer_usb"
 "Borri"	"ups"	"2"	"B400-R010-B/B400-R020-B/B400-R030-B/B400-R010-C/B400-R020-C/B400-R030-C"	"USB"	"blazer_usb"
 "Borri"	"ups"	"2"	"B500-060-B/B500-100-B/B500-060-C/B500-100-C"	"USB"	"blazer_usb"
@@ -221,7 +229,7 @@
 
 "Crown"	"ups"	"2"	"CMU-SP1200IEC"	"USB"	"nutdrv_qx port=auto vendorid=0001 productid=0000 protocol=hunnox langid_fix=0x0409 novendor noscanlangid"	# https://github.com/networkupstools/nut/pull/638 caveats at https://github.com/networkupstools/nut/issues/1014
 
-"Cyber Energy"	"ups"	"3"	"Models with USB ID 0483:A430"	"USB"	"usbhid-ups"	# https://alioth-lists.debian.net/pipermail/nut-upsdev/2024-February/007966.html
+"Cyber Energy"	"ups"	"3"	"Models with USB"	"USB"	"usbhid-ups"	# https://alioth-lists.debian.net/pipermail/nut-upsdev/2024-February/007966.html https://alioth-lists.debian.net/pipermail/nut-upsdev/2024-June/008002.html
 
 "Cyber Power Systems"	"ups"	"1"	"550SL"	""	"genericups upstype=7"
 "Cyber Power Systems"	"ups"	"1"	"725SL"	""	"genericups upstype=7"
@@ -246,7 +254,8 @@
 "Cyber Power Systems"	"ups"	"3"	"CP1350AVRLCD"	"USB"	"usbhid-ups"
 "Cyber Power Systems"	"ups"	"3"	"CP1500AVRLCD"	"USB"	"usbhid-ups"
 "Cyber Power Systems"	"ups"	"3"	"CP850PFCLCD"	"USB"	"usbhid-ups"	# https://github.com/networkupstools/nut/issues/605
-"Cyber Power Systems"	"ups"	"3"	"CP1350PFCLCD"	"USB"	"usbhid-ups"	# https://alioth-lists.debian.net/pipermail/nut-upsuser/2023-October/013441.html 
+"Cyber Power Systems"	"ups"	"3"	"CP1350PFCLCD"	"USB"	"usbhid-ups"	# https://alioth-lists.debian.net/pipermail/nut-upsuser/2023-October/013441.html
+"Cyber Power Systems"	"ups"	"3"	"CP1350EPFCLCD"	"USB"	"usbhid-ups"
 "Cyber Power Systems"	"ups"	"3"	"CP1500PFCLCD"	"USB"	"usbhid-ups"	# https://www.cyberpowersystems.com/product/ups/cp1500pfclcd/ https://github.com/networkupstools/nut/issues/520
 "Cyber Power Systems"	"ups"	"3"	"CPJ500"	"USB"	"usbhid-ups"	# https://www.cyberpower.com/jp/ja/product/sku/cpj500#downloads https://github.com/networkupstools/nut/issues/1403
 "Cyber Power Systems"	"ups"	"3"	"CP900AVR"	"USB"	"usbhid-ups"
@@ -354,6 +363,7 @@
 "Eaton"	"ups"	"5"	"5S"	"USB port"	"usbhid-ups"
 "Eaton"	"ups"	"5"	"5SC"	"USB port"	"usbhid-ups"
 "Eaton"	"ups"	"5"	"5P"	"USB port"	"usbhid-ups"
+"Eaton"	"ups"	"5"	"9E"	"USB port"	"usbhid-ups"
 "Eaton"	"ups"	"5"	"9SX"	"USB port"	"usbhid-ups"
 "Eaton"	"ups"	"5"	"9PX"	"USB port"	"usbhid-ups"
 "Eaton"	"ups"	"5"	"9PX Split Phase 6/8/10 kVA"	"USB port"	"usbhid-ups"
@@ -609,7 +619,7 @@
 "Legrand"	"ups"	"2"	"Keor Line RT"	"Serial"	"nutdrv_qx"
 "Legrand"	"ups"	"2"	"Keor Line RT"	"USB"	"nutdrv_qx"
 "Legrand"	"ups"	"2"	"Keor LP"	"Serial"	"nutdrv_qx"
-"Legrand"	"ups"	"2"	"Keor Multiplug"	"USB"	"nutdrv_qx"	# NOTE: As of 2023 reports, the "NEW Keor Multiplug" is not supported (also by older vendor SW)
+"Legrand"	"ups"	"2"	"Keor Multiplug"	"USB"	"nutdrv_qx"	# NOTE: As of 2023 reports, the 'NEW Keor Multiplug' is not supported (also by older vendor SW)
 "Legrand"	"ups"	"2"	"Keor S"	"Serial"	"nutdrv_qx"
 "Legrand"	"ups"	"2"	"Keor S"	"USB"	"nutdrv_qx"
 "Legrand"	"ups"	"3"	"Keor PDU"	"USB"	"usbhid-ups"
@@ -1111,8 +1121,8 @@
 "Riello"	"ups"	"3"	"(various)"	"Netman Plus 101 SNMP Box"	"snmp-ups"
 "Riello"	"ups"	"3"	"(various)"	"Netman Plus 102 SNMP Card"	"snmp-ups"
 "Riello"	"ups"	"3"	"(various)"	"Netman Plus 202 SNMP Card"	"snmp-ups"
-"Riello"	"ups"	"3"	"(various)"	"Netman 204 SNMP Card"	"snmp-ups"	# Note: in https://github.com/networkupstools/nut/issues/1878 submitted not as "Netman Plus", clarification requested
-"Riello"	"ups"	"3"	"(various)"	"Netman 208 SNMP Card"	"snmp-ups"	# Note: in https://github.com/networkupstools/nut/issues/1878 submitted not as "Netman Plus", clarification requested
+"Riello"	"ups"	"3"	"(various)"	"Netman 204 SNMP Card"	"snmp-ups"	# Note: in https://github.com/networkupstools/nut/issues/1878 submitted not as 'Netman Plus', clarification requested
+"Riello"	"ups"	"3"	"(various)"	"Netman 208 SNMP Card"	"snmp-ups"	# Note: in https://github.com/networkupstools/nut/issues/1878 submitted not as 'Netman Plus', clarification requested
 
 "Rocketfish"	"ups"	"3"	"RF-1000VA / RF-1025VA"	"USB"	"usbhid-ups"
 
@@ -1201,6 +1211,8 @@
 "Tecnoware"	"ups"	"2"	"UPS ERA LCD 0.65"	"USB"	"blazer_usb langid_fix=0x409"
 "Tecnoware"	"ups"	"2"	"UPS ERA PLUS 1100"	"USB"	"blazer_usb"	# https://www.tecnoware.com/Prodotti/FGCERAPL1100/ups-era-plus-1100.aspx https://github.com/networkupstools/nut/issues/747
 
+"Texas Instruments"	"ups"	"5"	"INA219"	"hwmon"	"hwmon_ina219"
+
 "Tripp Lite"	"ups"	"1"	"(various)"	"Lan 2.2 interface - black 73-0844 cable"	"genericups upstype=5"
 "Tripp Lite"	"ups"	"3"	"1500 LCD"	"USB"	"usbhid-ups"
 "Tripp Lite"	"ups"	"3"	"AVR550U"	"USB (protocol 2010)"	"usbhid-ups"	# http://www.tripplite.com/en/products/model.cfm?txtSeriesID=930&txtModelID=3090
@@ -1382,6 +1394,8 @@
 
 "Viewsonic"	"ups"	"1"	"PowerES"	"420E"	"optiups"
 
+"Visench"	"ups"	"1"	"C1K"	"(/dev/ttyCH341USB0 with USB ID 1a86:7523)"	"nutdrv_qx"	# https://github.com/networkupstools/nut/issues/2395 : Visench C1K; mfr/model are strings of `2`'s; USB ID identifies as QinHeng Electronics CH340 serial converter chip
+
 "Vivaldi"	"ups"	"1"	"EA200 LED"	"USB"	"richcomm_usb"
 
 "Voltronic Power"	"ups"	"2"	"Apex 1KVA"	"Serial"	"nutdrv_qx"
diff --git a/data/html/Makefile.am b/data/html/Makefile.am
index 19436e12da..1327c724b9 100644
--- a/data/html/Makefile.am
+++ b/data/html/Makefile.am
@@ -12,7 +12,7 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/docs/FAQ.txt b/docs/FAQ.txt
index a04d1d29f2..806bb41e46 100644
--- a/docs/FAQ.txt
+++ b/docs/FAQ.txt
@@ -281,6 +281,13 @@ with 'upsdrvsvcctl resync' and then manage those with commands like
 'upsdrvsvcctl stop' and 'upsdrvsvcctl start' (note that on other
 systems this tool may be not pre-installed via packaging).
 
+In fact, service instances prepared by the `nut-driver-enumerator` script
+and service based on contents of your `ups.conf` file and automatically
+maintained by the respective framework can conflict with manual execution
+of drivers, so `upsdrvctl` would emit a warning in NUT builds with that
+capability (can be silenced by exporting a `NUT_QUIET_INIT_NDE_WARNING`
+environment variable with any value).
+
 *Answer 2*
 
 Some USB UPS devices have unreliable USB to serial interfaces.
@@ -314,7 +321,8 @@ remembers the 'last state' when the UPS restarts.
 One solution is to change your shutdown scripts so you never reach
 that point.  You *want* the system to die without reaching the
 part where the kernel tells it to shut down.  A possible script
-might look like this:
+might look like this (see `scripts/systemd/nutshutdown` in NUT
+sources for a more streamlined and modern variant):
 
 ------
 	# other shutdown stuff here (mount -o remount,ro ...)
diff --git a/docs/Makefile.am b/docs/Makefile.am
index 33f0ff5d77..d8b18a382b 100644
--- a/docs/Makefile.am
+++ b/docs/Makefile.am
@@ -1,9 +1,37 @@
 # Network UPS Tools: main docs
 
+# FIXME: There is a lot of shell-scripting below which gets processed by
+# whatever system shell there is. While bash handles expressions like
+#   VAL="`cmd "some params"`"
+# in a way that "some params" are a single token passed to "cmd" as an
+# argument, and the stdout of such command execution is collected into a
+# single-token string as "VAL" (even if with white-spaces). Some other
+# shells, e.g. "ksh" seems to actively dislike unbalanced double-quotes
+# inside the backticks (e.g. matched in some grep/sed regexes below),
+# although generally the approach works for such "VAL" assignments too.
+# Note that the newer "$(...)" syntax is not portable, older shells
+# have no idea about it, and it is cumbersome with `make` substitution.
+# Keep a lookout with multi-platform NUT CI jobs, and try to use single
+# quotes where possible (e.g. where pre-expanded `make` variables are
+# involved - so shell should not process them again anyway).
+
 MAINTAINERCLEANFILES = Makefile.in .dirstamp
 EXTRA_DIST =
 
-all: doc
+# Note: "doc" ensures the `configure`-specified list of documents we actually
+# want, while the default generated "all: all-am" target historically causes
+# some but not all of these targets to get built (e.g. ChangeLog html/pdf is
+# usually not made there). Post-processing "doc" as part of "all" helps
+# ensure that we do not rebuild stuff in vain during parallel builds (where
+# "all-am" and "doc" would be unordered parallel goals of the "all" target)
+# while getting those further goals achieved eventually in the default build.
+# Crucially, this allows to make sure "ChangeLog(.adoc*)" files have been
+# generated once (can take a looong while), settled into place, and only then
+# we revisit them for html/pdf rendering (another long while) without randomly
+# confusing the system with new timestamps and needless regenerations later on.
+all:
+	@echo "  DOC-FOLLOW-UP	Basic 'make $@' in `pwd` is done, following up with 'make doc' to ensure complex document types"
+	+@$(MAKE) $(AM_MAKEFLAGS) doc
 
 # Is "egrep == grep -E" always valid? (maybe all a job for configure.ac)
 #EGREP = egrep
@@ -88,6 +116,7 @@ ALL_TXT_SRC = nut-names.txt daisychain.txt \
  release-notes.txt ChangeLog.txt solaris-usb.txt
 
 ASPELL_FILTER_PATH = @ASPELL_FILTER_PATH@
+# NOTE: This can be set by caller such as nut-website builder:
 NUT_SPELL_DICT = nut.dict
 EXTRA_DIST += $(ALL_TXT_SRC) $(SHARED_DEPS) $(IMAGE_FILES) \
  $(IMAGE_LOGO_FILES) $(IMAGE_LOGO_FILES_JENKINS_NUT) $(CABLES_IMAGES) $(NUT_SPELL_DICT) \
@@ -121,7 +150,7 @@ ASCIIDOC_PDF = user-manual.pdf \
 	FAQ.pdf
 
 SUBDIRS = man cables
-SUFFIXES = .txt .html .pdf -spellchecked .txt-prepped
+SUFFIXES = .txt .html .pdf .txt-spellchecked .txt-prepped
 
 # This list is defined by configure script choices and options:
 CHECK_LOCAL_TARGETS = @DOC_CHECK_LIST@
@@ -131,6 +160,7 @@ endif WITH_SPELLCHECK
 check-local: $(CHECK_LOCAL_TARGETS)
 
 # Make sure sources are there for out-of-tree builds:
+all-local all-am-local \
 @DOC_BUILD_LIST@ $(ASCIIDOC_PDF) $(ASCIIDOC_HTML_SINGLE) $(ASCIIDOC_HTML_CHUNKED): $(abs_top_builddir)/docs/.prep-src-docs
 
 # This list is defined by configure script choices and options:
@@ -144,11 +174,36 @@ all-docs: docs
 
 check-docs: check-pdf check-html-single check-html-chunked check-man
 
+# Not called by default, but handy for maintainers to check which words
+# in the custom dictionary are used or not by the current NUT codebase.
+# Note that historically many words were added to facilitate rendition
+# of the nut-website (long ago splintered from main nut repository),
+# but since recently it has a way to track its own additions to the
+# dictionary file. This code should help populate it as well, and keep
+# only relevant entries in the appropriate corner of the sources.
+# Note this can take 5-10 minutes!
+spellcheck-report-dict-usage: $(NUT_SPELL_DICT).usage-report
+
 pdf: $(ASCIIDOC_PDF)
 # also build the HTML manpages with these targets
 html-single: $(ASCIIDOC_HTML_SINGLE)
 html-chunked: $(ASCIIDOC_HTML_CHUNKED)
 
+# htmldocdir and pdfdir are set by autoconf/automake
+htmldoc_DATA =
+if WITH_HTML_SINGLE
+htmldoc_DATA += $(ASCIIDOC_HTML_SINGLE)
+endif
+# FIXME: Install tools refuse to work with directories in this context
+# and html-chunked documentation has a separate tree per document.
+# Maybe an "(un)install-data-local" or "install-data-hook" for this?
+#if WITH_HTML_CHUNKED
+#htmldoc_DATA += $(ASCIIDOC_HTML_CHUNKED)
+#endif
+if WITH_PDFS
+pdf_DATA = $(ASCIIDOC_PDFS)
+endif
+
 # the "for" loops might better use $^ but it might be not portable
 check-pdf: $(ASCIIDOC_PDF)
 	@FAILED=""; LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
@@ -158,13 +213,104 @@ check-pdf: $(ASCIIDOC_PDF)
 	    echo "FAILED PDF sanity check for:$$FAILED" >&2 ; file $$FAILED >&2 ; exit 1; \
 	fi; echo "PASSED PDF sanity check"; exit 0
 
+# Regarding ChangeLog check: sometimes asciidoc gives up early
+# (we have megabytes of text and thousands of sections here).
+# In some cases, the intermediate XML is broken and a2x=>xmllint
+# notices it. In others, it is truncated at just the right place
+# structurally and leads to a short HTML with only part of the
+# expected contents. We should no longer have several processes
+# trying to create the files involved (or rather do so atomically
+# and rename into final path, in case we still have competition
+# here); earlier when several generators appended to the same
+# file we could have several copies overlaid, with one of the
+# document's copies starting mid-sentence of another.
+# The two expected mentions are in the table of contents and
+# in the eventual section. Checking for first/second entries,
+# and not exactly two mentions, should allow to catch the case
+# of overlapping documents. Checking for the last entry allows
+# to catch incomplete parses, where asciidoc gave up early.
+# NOTE: Technically it may be more than two, if the author and
+# date were used several times in the original ChangeLog file
+# (either with different e-mails, or if different author's work
+# is interleaved during the day, e.g. many PRs merged, and no
+# CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR=true setting was in place.
+# NOTE: No dependencies, avoids (re-)generation and log messages.
+ChangeLog.html-contentchecked:
+	@FAILED=""; \
+	 if [ -s '$(top_builddir)/ChangeLog' ] && [ -s ChangeLog.html ] ; then \
+	    SECOND_ENTRY="`grep -E '^[0-9]' '$(top_builddir)/ChangeLog' | head -2 | tail -1 | sed 's/ *[\"<].*//'`" || SECOND_ENTRY="" ; \
+	    FIRST_ENTRY="`grep -E '^[0-9]' '$(top_builddir)/ChangeLog' | head -1 | sed 's/ *[\"<].*//'`" || FIRST_ENTRY="" ; \
+	    LAST_ENTRY="`grep -E '^[0-9]' '$(top_builddir)/ChangeLog' | tail -1 | sed 's/ *[\"<].*//'`" || LAST_ENTRY="" ; \
+	    if [ -n "$${FIRST_ENTRY}" ] ; then \
+	        O="`grep -cE "^$${FIRST_ENTRY}" '$(top_builddir)/ChangeLog'`" ; \
+	        N="`grep -cE "title.*$${FIRST_ENTRY}" 'ChangeLog.html'`" ; \
+	        MIN="`expr $${O} + 1`"     && [ "$${MIN}" -gt 0 ] 2>/dev/null || MIN=1 ; \
+	        MAX="`expr $${O} + $${O}`" && [ "$${MAX}" -gt 2 ] 2>/dev/null || MAX=2 ; \
+	        if [ "$${N}" -lt "$${MIN}" ] || [ "$${N}" -gt "$${MAX}" ]; then \
+	            echo "FAILED ChangeLog.html check: does not contain expected first entry the right amount of times (huge doc, must have got aborted mid-way): $${FIRST_ENTRY} (seen $${N} times, expected between $${MIN} and $${MAX})" >&2 ; \
+	            if [ -z "$$FAILED" ] ; then \
+	                echo "Expected size over 3MB (for common builds):" >&2 ; \
+	                ls -la "ChangeLog.html" '$(top_builddir)/ChangeLog'* >&2 ; \
+	                FAILED="ChangeLog.html" ; \
+	            fi ; \
+	        fi ; \
+	    fi; \
+	    if [ -n "$${SECOND_ENTRY}" ] ; then \
+	        O="`grep -cE "^$${SECOND_ENTRY}" '$(top_builddir)/ChangeLog'`" ; \
+	        N="`grep -cE "title.*$${SECOND_ENTRY}" 'ChangeLog.html'`" ; \
+	        MIN="`expr $${O} + 1`"     && [ "$${MIN}" -gt 0 ] 2>/dev/null || MIN=1 ; \
+	        MAX="`expr $${O} + $${O}`" && [ "$${MAX}" -gt 2 ] 2>/dev/null || MAX=2 ; \
+	        if [ "$${N}" -lt "$${MIN}" ] || [ "$${N}" -gt "$${MAX}" ]; then \
+	            echo "FAILED ChangeLog.html check: does not contain expected second entry the right amount of times (huge doc, must have got aborted mid-way): $${SECOND_ENTRY} (seen $${N} times, expected between $${MIN} and $${MAX})" >&2 ; \
+	            if [ -z "$$FAILED" ] ; then \
+	                echo "Expected size over 3MB (for common builds):" >&2 ; \
+	                ls -la "ChangeLog.html" '$(top_builddir)/ChangeLog'* >&2 ; \
+	                FAILED="ChangeLog.html" ; \
+	            fi ; \
+	        fi ; \
+	    fi; \
+	    if [ -n "$${LAST_ENTRY}" ] ; then \
+	        O="`grep -cE "^$${LAST_ENTRY}" '$(top_builddir)/ChangeLog'`" ; \
+	        N="`grep -cE "title.*$${LAST_ENTRY}" 'ChangeLog.html'`" ; \
+	        MIN="`expr $${O} + 1`"     && [ "$${MIN}" -gt 0 ] 2>/dev/null || MIN=1 ; \
+	        MAX="`expr $${O} + $${O}`" && [ "$${MAX}" -gt 2 ] 2>/dev/null || MAX=2 ; \
+	        if [ "$${N}" -lt "$${MIN}" ] || [ "$${N}" -gt "$${MAX}" ]; then \
+	            echo "FAILED ChangeLog.html check: does not contain expected last entry the right amount of times (huge doc, must have got aborted mid-way): $${LAST_ENTRY} (seen $${N} times, expected between $${MIN} and $${MAX})" >&2 ; \
+	            if [ -z "$$FAILED" ] ; then \
+	                echo "Expected size over 3MB (for common builds):" >&2 ; \
+	                ls -la "ChangeLog.html" '$(top_builddir)/ChangeLog'* >&2 ; \
+	                FAILED="ChangeLog.html" ; \
+	            fi ; \
+	        fi ; \
+	    fi; \
+	    if [ x"$$FAILED" = x ] ; then \
+	        echo "PASSED $@" >&2 ; \
+	        exit 0 ; \
+	    fi ; \
+	    if [ x"$$FAILED" != x ] && [ -s '$(top_builddir)/ChangeLog.adoc' ] \
+	    && [ "`head -1 $(top_builddir)/ChangeLog.adoc`" = "=== Failed to generate the ChangeLog" ] \
+	    ; then \
+	        FAILED="" ; \
+	    fi; \
+	 fi; \
+	 if [ x"$$FAILED" = x ] ; then \
+	    echo "SKIPPED $@ because input files were not available" >&2 ; \
+	    exit 0 ; \
+	 fi ; \
+	 exit 1
+
 check-html-single: $(ASCIIDOC_HTML_SINGLE)
-	@FAILED=""; LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
-	for F in $(ASCIIDOC_HTML_SINGLE) ; do \
+	+@FAILED=""; LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
+	 for F in $(ASCIIDOC_HTML_SINGLE) ; do \
 	    test -s "$$F" && { file "$$F" | $(EGREP) -i '(XML|HTML.*document)' > /dev/null ; } || FAILED="$$FAILED $$F" ; \
-	done; if test -n "$$FAILED" ; then \
+	    case "$$F" in \
+	        *ChangeLog*) if [ -s '$(top_builddir)/ChangeLog' ] ; then \
+	                $(MAKE) $(AM_MAKEFLAGS) "`basename "$$F"`"-contentchecked || FAILED="$$FAILED $$F" ; \
+	            fi ;; \
+	    esac ; \
+	 done; if test -n "$$FAILED" ; then \
 	    echo "FAILED HTML-single sanity check for:$$FAILED" >&2 ; file $$FAILED >&2 ; exit 1; \
-	fi; echo "PASSED HTML-single sanity check"; exit 0
+	 fi; echo "PASSED HTML-single sanity check"; exit 0
 
 check-html-chunked: $(ASCIIDOC_HTML_CHUNKED)
 	@FAILED=""; LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
@@ -185,12 +331,12 @@ check-html-chunked: $(ASCIIDOC_HTML_CHUNKED)
 # chosen during configure script execution. The "all-man" and "all-html"
 # rules build everything documented.
 check-man all-man man-man all-html html-man:
-	+cd $(top_builddir)/docs/man/ && $(MAKE) $(AM_MAKEFLAGS) -f Makefile $@
+	+cd $(abs_top_builddir)/docs/man/ && $(MAKE) $(AM_MAKEFLAGS) -f Makefile $@
 
 man:
-	+cd $(top_builddir)/docs/man/ && $(MAKE) $(AM_MAKEFLAGS) -f Makefile all
+	+cd $(abs_top_builddir)/docs/man/ && $(MAKE) $(AM_MAKEFLAGS) -f Makefile all
 
-CLEANFILES = *.xml *.html *.pdf *-spellchecked docbook-xsl.css docinfo.xml.in.tmp
+CLEANFILES = *.xml *.html *.pdf *-spellchecked *-contentchecked docbook-xsl.css docinfo.xml.in.tmp
 CLEANFILES += $(top_builddir)/INSTALL.nut $(top_builddir)/UPGRADING $(top_builddir)/NEWS $(top_builddir)/ChangeLog.adoc $(top_builddir)/README
 CLEANFILES += $(top_builddir)/*.adoc-parsed *.adoc-parsed
 
@@ -218,21 +364,38 @@ DOCBUILD_FILTER_GITHUB_LINKS = { \
 # The $< is okay here, it is used in a suffix rule below
 DOCBUILD_CONVERT_GITHUB_LINKS = { \
     echo "  DOC-ASCIIDOC-GITHUB-LINKS    Parsing GitHub link patterns $< => $@"; \
-    cat "$<" | $(DOCBUILD_FILTER_GITHUB_LINKS) > "$@.tmp" \
-    && mv -f "$@.tmp" "$@" \
+    cat "$<" | $(DOCBUILD_FILTER_GITHUB_LINKS) > "$@.tmp.$$$$" \
+    && mv -f "$@.tmp.$$$$" "$@" \
 ; }
 
 .adoc.adoc-parsed:
 	@$(DOCBUILD_CONVERT_GITHUB_LINKS)
 
-$(top_builddir)/ChangeLog:
-	+@echo "  DOC-CHANGELOG-GENERATE	$@" \
+$(top_builddir)/ChangeLog.adoc-parsed: $(top_builddir)/ChangeLog.adoc
+
+dummy:
+$(top_builddir)/ChangeLog: dummy
+	@+echo "  DOC-CHANGELOG-GENERATE-WRAPPER	$@ : call parent Makefile to decide if (re-)generation is needed" \
 	 && cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) $(@F)
 
 # BSD Make dislikes the path resolution here and does not always populate "$<"
 # (and claims why: "Using $< in a non-suffix rule context is a GNUmake idiom"),
 # but it has a "$?" for "list of dependencies that are newer than the target".
 # For more details see https://man.freebsd.org/cgi/man.cgi
+if WITH_PDF_NONASCII_TITLES
+A2X_ASCII_IDS =
+else !WITH_PDF_NONASCII_TITLES
+A2X_ASCII_IDS = ":ascii-ids:\n"
+endif !WITH_PDF_NONASCII_TITLES
+
+# Probably due to the web of makefiles and an overwhelmed job server in some
+# implementations, during parallel builds we can end up scheduling several
+# threads creating this asciidoc (and adoc-parsed later). This step only
+# costs a few seconds, however the updated timestamp may cause new HTML/PDF
+# builds which cost a lot more. Below we try a few ways to detect a build
+# already running and bail out early if the file exists. Otherwise we bite
+# the bullet and spend a few seconds, and then re-check if another thread
+# did exist and finished first.
 $(top_builddir)/ChangeLog.adoc: $(top_builddir)/ChangeLog
 	@INPUT="$?"; \
 	 test -n "$${INPUT}" || INPUT="$$(top_builddir)/ChangeLog" ; \
@@ -240,11 +403,13 @@ $(top_builddir)/ChangeLog.adoc: $(top_builddir)/ChangeLog
 	 || { \
 	     MSG="FAILED to resolve input or output filename with this make implementation, or input was not generated!"; \
 	     echo "  DOC-CHANGELOG-ASCIIDOC	SKIP: $${MSG}" >&2; \
-	     test -n "$@" && echo "$${MSG}" > "$@" ; \
+	     test -n "$@" && { printf '=== Failed to generate the ChangeLog\n\n%s\n\nNOTE: See https://github.com/networkupstools/nut/commits/master for change history.\n\n' "$${MSG}" > "$@" ; } ; \
 	     exit ; \
 	 } ; \
+	 W=10 ; while [ "$${W}" -gt 0 ] && find '$@.tmp.'* '$@' -newer "$${INPUT}" 2>/dev/null >/dev/null ; do sleep 1 ; W="`expr $$W - 1`"; done ; touch "$@.tmp.$$$$"; \
+	 if [ x"`find '$@' -newer "$${INPUT}" 2>/dev/null`" != x ] ; then echo "  DOC-CHANGELOG-ASCIIDOC	$${INPUT} => $@ : SKIP (keep existing)"; rm -f "$@.tmp.$$$$"; exit 0 ; fi ; \
 	 echo "  DOC-CHANGELOG-ASCIIDOC	$${INPUT} => $@" \
-	 && printf "ifdef::txt[]\n== Very detailed Change Log\nendif::txt[]\n\n" > "$@.tmp" \
+	 && printf "ifdef::txt[]\n== Very detailed Change Log\n"$(A2X_ASCII_IDS)"endif::txt[]\n\n" > "$@.tmp.$$$$" \
 	 && TABCHAR="`printf '\t'`" \
 	 && $(SED) \
 	        -e 's,^\([0-9a-zA-Z]\),=== \1,' \
@@ -255,8 +420,9 @@ $(top_builddir)/ChangeLog.adoc: $(top_builddir)/ChangeLog
 	        -e 's,^\([ '"$${TABCHAR}"'].*\)\([~|^]\),\1\\\2,g' \
 	        -e 's,\[\[\([^]]*\)\]\],[\1],g' \
 	        -e 's,^\(\s\s*\)\([0-9]\),\1{empty}\2,g' \
-	   < "$${INPUT}" >> "$@.tmp" \
-	 && mv -f "$@.tmp" "$@"
+	   < "$${INPUT}" >> "$@.tmp.$$$$" \
+	 && if [ x"`find '$@' -newer "$${INPUT}" 2>/dev/null`" != x ] ; then echo "  DOC-CHANGELOG-ASCIIDOC	$${INPUT} => $@ : SKIP (keep recently born competitor)"; rm -f "$@.tmp.$$$$"; \
+	    else mv -f "$@.tmp.$$$$" "$@" ; fi
 
 # Add other directory deps (not for local EXTRA_DIST) and generated contents
 FULL_USER_MANUAL_DEPS = $(USER_MANUAL_DEPS) $(SHARED_DEPS) \
@@ -303,7 +469,7 @@ A2X_COMMON_OPTS = $(ASCIIDOC_VERBOSE) \
 # As of version 8.6.9 it lies, and the argument is required for our distcheck
 # (and does affect PDF builds, as found during work on collision-avoidance -
 # true with at least asciidoc/a2x versions 9.0.0rc2).
-# For more details see issues https://github.com/asciidoc/asciidoc/issues/44
+# For more details see issues https://web.archive.org/web/20201207082352/https://github.com/asciidoc/asciidoc/issues/44
 # and https://github.com/networkupstools/nut/pull/281 (in short, attempts
 # to "fix" this warning broke NUT build). If this is to be retried later, see
 # https://github.com/networkupstools/nut/pull/281/commits/fe17861c4ea12679b3ebfefa8a6d692d79d99f2d
@@ -374,18 +540,33 @@ DOCBUILD_END = { \
 
 *.html: common.xsl xhtml.xsl
 .txt-prepped.html:
-	@A2X_OUTDIR="tmp/html-single.$(@F).$$$$" ; \
+	+@A2X_OUTDIR="tmp/html-single.$(@F).$$$$" ; \
 	 echo "  DOC-HTML Generating $@"; \
 	 $(DOCBUILD_BEGIN) ; RES=0; \
-	 $(A2X) $(A2X_COMMON_OPTS) --attribute=xhtml11_format --format=xhtml --xsl-file=$(srcdir)/xhtml.xsl "$(<D)/`basename "$(<F)" -prepped`" || RES=$$? ; \
-	 $(DOCBUILD_END) ; exit $$RES
+	 $(A2X) $(A2X_COMMON_OPTS) --attribute=xhtml11_format --format=xhtml --xsl-file=$(srcdir)/xhtml.xsl "$(<D)/`basename '$(<F)' -prepped`" || RES=$$? ; \
+	 $(DOCBUILD_END) ; \
+	 case "$(@F)" in \
+	    *ChangeLog*) if [ -s '$(top_builddir)/ChangeLog' ] ; then \
+	            $(MAKE) $(AM_MAKEFLAGS) "`basename '$(@F)'`"-contentchecked || RES=$$? ; \
+	            if [ "$$RES" != 0 ] ; then \
+	                echo "  DOC-HTML Generating $@ (retry once)" >&2; \
+	                rm -f "$@"; \
+	                A2X_OUTDIR="tmp/html-single.$(@F).$$$$-retry" ; \
+	                $(DOCBUILD_BEGIN) ; RES=0; rm -f "`basename '$(@F)'`"-contentchecked || true ; \
+	                $(A2X) $(A2X_COMMON_OPTS) --attribute=xhtml11_format --format=xhtml --xsl-file=$(srcdir)/xhtml.xsl "$(<D)/`basename '$(<F)' -prepped`" || RES=$$? ; \
+	                $(DOCBUILD_END) ; \
+	                $(MAKE) $(AM_MAKEFLAGS) "`basename '$(@F)'`"-contentchecked || RES=$$? ; \
+	            fi ; \
+	        fi ;; \
+	 esac ; \
+	 exit $$RES
 
 *.chunked: common.xsl chunked.xsl
 .txt-prepped.chunked:
 	@A2X_OUTDIR="tmp/html-chunked.$(@F).$$$$" ; \
 	 echo "  DOC-HTML-CHUNKED Generating $@"; \
 	 $(DOCBUILD_BEGIN) ; RES=0; \
-	 $(A2X) $(A2X_COMMON_OPTS) --attribute=chunked_format --format=chunked --xsl-file=$(srcdir)/chunked.xsl "$(<D)/`basename "$(<F)" -prepped`" || RES=$$? ; \
+	 $(A2X) $(A2X_COMMON_OPTS) --attribute=chunked_format --format=chunked --xsl-file=$(srcdir)/chunked.xsl "$(<D)/`basename '$(<F)' -prepped`" || RES=$$? ; \
 	 $(DOCBUILD_END) ; exit $$RES
 
 # Note: non-HTML a2x modes may ignore the destination directory
@@ -394,7 +575,7 @@ DOCBUILD_END = { \
 	@A2X_OUTDIR="tmp/pdf.$(@F).$$$$" ; \
 	 echo "  DOC-PDF  Generating $@"; \
 	 $(DOCBUILD_BEGIN) ; RES=0; \
-	 $(A2X) $(A2X_COMMON_OPTS) --attribute=pdf_format --format=pdf -a docinfo1 "$(<D)/`basename "$(<F)" -prepped`" || RES=$$? ; \
+	 $(A2X) $(A2X_COMMON_OPTS) --attribute=pdf_format --format=pdf -a docinfo1 "$(<D)/`basename '$(<F)' -prepped`" || RES=$$? ; \
 	 $(DOCBUILD_END) ; exit $$RES
 
 # Used below for spellcheck and for .prep-src-docs
@@ -472,6 +653,10 @@ ASPELL_OUT_NOTERRORS = (^[ \t]*[\*\@]|^$$)
 SPELLCHECK_RECIPE_DEBUG_STREAM = /dev/null
 #SPELLCHECK_RECIPE_DEBUG_STREAM = &2
 
+# Note: if we do an interactive spell-check, it updates "nut.dict"
+# timestamp even if contents remain. If the caller left a copy of
+# the file as "$(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting",
+# and the dictionary was not in fact modified, restore the timestamp.
 $(SPELLCHECK_BUILDDIR)/$(SPELLCHECK_SRC_ONE)-spellchecked: $(SPELLCHECK_SRCDIR)/$(SPELLCHECK_SRC_ONE) $(abs_top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 	@LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
 	 if test x"$(SPELLCHECK_SRC_ONE)" = x ; then echo "SKIP: Bogus spellcheck call for empty target filename (with make target $@ from `pwd`)" >&2 ; exit 0; fi; \
@@ -485,12 +670,12 @@ $(SPELLCHECK_BUILDDIR)/$(SPELLCHECK_SRC_ONE)-spellchecked: $(SPELLCHECK_SRCDIR)/
 		/*) ;; \
 		*/*)	if [ x"$${REPORT_SRCDIR}" = x ] ; then \
 				echo EMPTY >$(SPELLCHECK_RECIPE_DEBUG_STREAM) ; \
-				REPORT_SRCDIR="`dirname "$(SPELLCHECK_SRC_ONE)"`"; \
+				REPORT_SRCDIR="`dirname '$(SPELLCHECK_SRC_ONE)'`"; \
 			else \
-				echo "APPEND: SPELLCHECK_SRCDIR='$(SPELLCHECK_SRCDIR)' SPELLCHECK_SRC_ONE='$(SPELLCHECK_SRC_ONE)' dirname='`dirname "$(SPELLCHECK_SRC_ONE)"`'" >$(SPELLCHECK_RECIPE_DEBUG_STREAM) ; \
-				REPORT_SRCDIR="$${REPORT_SRCDIR}/`dirname "$(SPELLCHECK_SRC_ONE)"`"; \
+				echo "APPEND: SPELLCHECK_SRCDIR='$(SPELLCHECK_SRCDIR)' SPELLCHECK_SRC_ONE='$(SPELLCHECK_SRC_ONE)' dirname='`dirname '$(SPELLCHECK_SRC_ONE)'`'" >$(SPELLCHECK_RECIPE_DEBUG_STREAM) ; \
+				REPORT_SRCDIR="$${REPORT_SRCDIR}/`dirname '$(SPELLCHECK_SRC_ONE)'`"; \
 			fi ; \
-			REPORT_SRC_ONE="`basename "$(SPELLCHECK_SRC_ONE)"`"; \
+			REPORT_SRC_ONE="`basename '$(SPELLCHECK_SRC_ONE)'`"; \
 			;; \
 		*) ;; \
 	 esac; \
@@ -505,8 +690,16 @@ $(SPELLCHECK_BUILDDIR)/$(SPELLCHECK_SRC_ONE)-spellchecked: $(SPELLCHECK_SRCDIR)/
 		*/) ;; \
 		*)  REPORT_SRCDIR="$${REPORT_SRCDIR}/" ;; \
 	 esac ; \
-	 echo "  ASPELL   Spell checking on $${REPORT_PREFIX}$${REPORT_SRCDIR}$${REPORT_SRC_ONE}"; \
-	 OUT="`(sed 's,^\(.*\)$$, \1,' | $(ASPELL) -a $(ASPELL_NUT_TEXMODE_ARGS) $(ASPELL_NUT_COMMON_ARGS) 2>&1) < "$(SPELLCHECK_SRCDIR)/$(SPELLCHECK_SRC_ONE)"`" \
+	 if [ x"$(SPELLCHECK_INTERACTIVE)" = xtrue ] ; then \
+		echo "  ASPELL   Spell checking (interactively) on $${REPORT_PREFIX}$${REPORT_SRCDIR}$${REPORT_SRC_ONE}"; \
+		LANG=$(ASPELL_ENV_LANG) LC_ALL=$(ASPELL_ENV_LANG) $(ASPELL) check $(ASPELL_NUT_COMMON_ARGS) '$(SPELLCHECK_SRCDIR)/$(SPELLCHECK_SRC_ONE)' || exit ; \
+		if [ -s $(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting ] && [ -s $(abs_srcdir)/$(NUT_SPELL_DICT) ] && diff $(abs_srcdir)/$(NUT_SPELL_DICT) $(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting >/dev/null ; then \
+			touch -r $(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting $(abs_srcdir)/$(NUT_SPELL_DICT) ; \
+		fi ; \
+	 else \
+		echo "  ASPELL   Spell checking on $${REPORT_PREFIX}$${REPORT_SRCDIR}$${REPORT_SRC_ONE}"; \
+	 fi ; \
+	 OUT="`(sed 's,^\(.*\)$$, \1,' | $(ASPELL) -a $(ASPELL_NUT_TEXMODE_ARGS) $(ASPELL_NUT_COMMON_ARGS) 2>&1) < '$(SPELLCHECK_SRCDIR)/$(SPELLCHECK_SRC_ONE)'`" \
 		&& { if test -n "$$OUT" ; then OUT="`echo "$$OUT" | $(EGREP) -b -v '$(ASPELL_OUT_NOTERRORS)' `" ; fi; \
 		     test -z "$$OUT" ; } \
 		|| { RES=$$? ; \
@@ -536,7 +729,7 @@ spellcheck:
 	 done ; \
 	 if test -n "$$FAILED" ; then \
 		echo "=====================================================================" ; \
-		echo "FAILED automatic spellcheck for the following sources (relative to `pwd`): $$FAILED" ; \
+		echo "FAILED automatic spellcheck for the following sources (relative to `pwd`) using custom dictionary file '$(NUT_SPELL_DICT)': $$FAILED" ; \
 		echo "=====================================================================" ; \
 		echo "Please 'cd $(abs_top_builddir) && make spellcheck-interactive'"; \
 		echo "to either fix document sources or update the dictionary of accepted"; \
@@ -563,7 +756,7 @@ spellcheck-sortdict: $(abs_builddir)/$(NUT_SPELL_DICT).sorted
 $(abs_builddir)/$(NUT_SPELL_DICT).sorted: $(abs_srcdir)/$(NUT_SPELL_DICT)
 	@cp -pf $(abs_srcdir)/$(NUT_SPELL_DICT) $(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting
 	@LANG=$(ASPELL_ENV_LANG); LC_ALL=$(ASPELL_ENV_LANG); export LANG; export LC_ALL; ( \
-	    WORDLIST="`tail -n +2 < "$?" | sort | uniq`"; \
+	    WORDLIST="`tail -n +2 < '$(?)' | sort | uniq`"; \
 	    WORDCOUNT="`echo "$$WORDLIST" | wc -l`"; \
 	    head -1 < "$?" | while read P L C E ; do echo "$$P $$L $$WORDCOUNT $$E"; break; done ; \
 	    echo "$$WORDLIST"; \
@@ -576,34 +769,86 @@ $(abs_builddir)/$(NUT_SPELL_DICT).sorted: $(abs_srcdir)/$(NUT_SPELL_DICT)
 
 DISTCLEANFILES = $(NUT_SPELL_DICT).bak-pre-sorting .$(NUT_SPELL_DICT).sorted $(NUT_SPELL_DICT).sorted
 
+# NOTE: In "make SPELLCHECK_INTERACTIVE=true ${docsrc}-spellchecked",
+# after an interactive "aspell check" we follow-up by a run of usual
+# non-interactive spell-checker to verify that the developer actually
+# has fixed all of the files that the tool had concerns about, and
+# that the touch-file is updated if the file is okay (to speed up
+# any future re-runs). We also must update all relevant *-spellchecked
+# touch-files after "make spellcheck-sortdict" which updates "nut.dict"
+# file which is a prerequisite for docs checks.
 spellcheck-interactive: 
-	@FAILED="" ; for docsrc in $(SPELLCHECK_SRC); do \
-		echo "Spell checking on $(SPELLCHECK_SRCDIR)/$$docsrc"; \
-		LANG=$(ASPELL_ENV_LANG) LC_ALL=$(ASPELL_ENV_LANG) $(ASPELL) check $(ASPELL_NUT_COMMON_ARGS) $(SPELLCHECK_SRCDIR)/$$docsrc || \
-			FAILED="$$FAILED $(SPELLCHECK_SRCDIR)/$$docsrc"; \
-	done ; \
-	if test -n "$$FAILED" ; then \
-		echo "FAILED interactive spellcheck for the following sources (relative to `pwd`): $$FAILED" >&2 ; \
+	@cp -pf $(abs_srcdir)/$(NUT_SPELL_DICT) $(abs_builddir)/$(NUT_SPELL_DICT).bak-pre-sorting
+	+@FAILED="" ; for docsrc in $(SPELLCHECK_SRC); do \
+		if test "$(SPELLCHECK_ENV_DEBUG)" != no ; then \
+			echo "ASPELL (INTERACTIVE) MAKEFILE DEBUG: Will see from `pwd` if '$(SPELLCHECK_SRCDIR)/$${docsrc}-spellchecked' is up to date" >&2; \
+		else true ; fi ; \
+		$(MAKE) $(AM_MAKEFLAGS) -s -f "$(abs_top_builddir)/docs/Makefile" SPELLCHECK_INTERACTIVE="true" SPELLCHECK_SRC="" SPELLCHECK_SRC_ONE="$${docsrc}" SPELLCHECK_BUILDDIR="$(SPELLCHECK_BUILDDIR)" SPELLCHECK_SRCDIR="$(SPELLCHECK_SRCDIR)" "$(SPELLCHECK_BUILDDIR)/$${docsrc}-spellchecked" \
+		|| FAILED="$$FAILED $(SPELLCHECK_SRCDIR)/$$docsrc"; \
+	 done ; \
+	 if test -n "$$FAILED" ; then \
+		echo "FAILED interactive spellcheck for the following sources (relative to `pwd`) using custom dictionary file '$(NUT_SPELL_DICT)': $$FAILED" >&2 ; \
 		exit 1; \
-	fi ; exit 0
-	+$(MAKE) $(AM_MAKEFLAGS) spellcheck-sortdict
+	 fi ; \
+	 $(MAKE) $(AM_MAKEFLAGS) spellcheck-sortdict || exit ; \
+	 for docsrc in $(SPELLCHECK_SRC); do \
+		if test -e "$(SPELLCHECK_BUILDDIR)/$${docsrc}-spellchecked" ; then \
+			touch "$(SPELLCHECK_BUILDDIR)/$${docsrc}-spellchecked" ; \
+		fi ; \
+	 done
 	@echo "------------------------------------------------------------------------"; \
 	 echo "Custom dictionary file $(NUT_SPELL_DICT) may have been updated now."; \
-	 echo "Use 'git add -p docs/$(NUT_SPELL_DICT) && git checkout -- docs/$(NUT_SPELL_DICT) && make spellcheck-sortdict && git add -p docs/$(NUT_SPELL_DICT)'"; \
+	 echo "Use e.g. 'git add -p docs/$(NUT_SPELL_DICT) && git checkout -- docs/$(NUT_SPELL_DICT) && make spellcheck-sortdict && git add -p docs/$(NUT_SPELL_DICT)'"; \
 	 echo "to review changes (please DO NOT REMOVE LINES that aspell chose to drop,"; \
 	 echo "because other systems might not know these words in their system dictionaries)"; \
 	 echo "------------------------------------------------------------------------"
 
 else !HAVE_ASPELL
-# This rule woulf probably just fail; normally with no ASPELL there are no callers for it
+# This rule would probably just fail; normally with no ASPELL there are no callers for it
 */*-spellchecked *-spellchecked: Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
-	@echo "  SKIP-ASPELL   $@ : Documentation spell check not available since 'aspell' was not found." >&2
+	@echo "  SKIP-ASPELL   $@ : Documentation spell check not available since 'aspell' was not found (or missing its English dictionary)." >&2
 spellcheck:
-	@echo "Documentation spell check not available since 'aspell' was not found."
+	@echo "Documentation spell check not available since 'aspell' was not found (or missing its English dictionary)."
 spellcheck-interactive:
-	@echo "Documentation spell check not available since 'aspell' was not found."
+	@echo "Documentation spell check not available since 'aspell' was not found (or missing its English dictionary)."
 endif !HAVE_ASPELL
 
+# Note that NUT_SPELL_DICT may be an include snippet without the header line.
+# To exclude files like `docs/nut.dict` or `nut-website.dict(.addons)` from
+# the usage lookups, we assume that a `*.dict*` pattern fits any used names.
+# Entries prefixed with '+++' mean something used in NUT sources in context
+# that aspell is likely to treat as a word (standalone or surrounded by certain
+# chars); otherwise in entries prefixed with '---' we print hit counts and
+# contents (if any, ending with '^^^') for the character pattern across the
+# whole Git-tracked codebase (case-insensitively for good measure).
+# Note this can take 5-10 minutes!
+# TOTHINK: Constrain to (caller-specified or default) SPELLCHECK_SRC?
+$(NUT_SPELL_DICT).usage-report: $(NUT_SPELL_DICT)
+	@echo "Preparing $@"; \
+	 LANG=C; LC_ALL=C; export LANG; export LC_ALL; \
+	 grep -v -E '^personal_ws' < $? \
+	 | while read W ; do ( \
+		cd "$(abs_top_srcdir)" || exit ; \
+		git grep -q "$$W" -- ':!*.dict*' || git grep -qE "[0-9_,./\ -]$$W[0-9_,./\ -]" -- ':!*.dict*' ) \
+		&& echo "+++ $$W" \
+		|| ( \
+			HITS_CS="`git grep "$$W" -- ':!*.dict*'`" || true; \
+			HITS_CI="`git grep -i "$$W" -- ':!*.dict*'`" || true; \
+			if [ -n "$$HITS_CS" ] ; then HITC_CS="`echo "$$HITS_CS" | wc -l`" ; else HITC_CS=0; fi; \
+			if [ -n "$$HITS_CI" ] ; then HITC_CI="`echo "$$HITS_CI" | wc -l`" ; else HITC_CI=0; fi; \
+			printf '%s (%d case-sensitive/%d case-insensitive)\n' "--- $$W" "$$HITC_CS" "$$HITC_CI"; \
+			if [ "$$HITC_CS" != 0 ] ; then echo "$$HITS_CS" ; echo "^^^"; else \
+				if [ "$$HITC_CI" != 0 ] ; then echo "$$HITS_CI" ; echo "^^^"; fi; \
+			fi; \
+		); \
+	 done > "$@.tmp.$$$$" \
+	 && test -f "$@.tmp.$$$$" \
+	 && mv -f "$@.tmp.$$$$" "$@"
+	@echo "Reporting words from $? possibly not used in current inspected code base revision under $(abs_top_srcdir)" >&2 ; \
+	 grep -E '^--- ' < "$@" | grep '(0 ' || echo "SUCCESS: None found"
+
+CLEANFILES += $(NUT_SPELL_DICT).usage-report.tmp
+MAINTAINERCLEANFILES += $(NUT_SPELL_DICT).usage-report
 
 # When building out-of-tree, be sure to have all asciidoc resources
 # under the same dir structure (tool limitation)
@@ -621,7 +866,7 @@ $(abs_top_builddir)/docs/.prep-src-docs: $(PREP_SRC)
 	    COUNT=0; \
 	    for F in $(PREP_SRC) ; do \
 	        case "$$F" in \
-	            /*) F="`echo "$$F" | sed "s#^$(abs_top_srcdir)/*#./#"`"; \
+	            /*) F="`echo "$$F" | sed 's#^$(abs_top_srcdir)/*#./#'`"; \
 	                if test x"$${linkroot}" = x"$(abs_builddir)" ; then \
 	                    linkroot="$(abs_top_builddir)" ; \
 	                    cd "$(abs_top_builddir)" ; \
@@ -647,7 +892,7 @@ $(abs_top_builddir)/docs/.prep-src-docs: $(PREP_SRC)
 	    linksrcroot="$(abs_srcdir)" ; \
 	    for F in `echo $(PREP_SRC) | tr ' ' '\n' | sort -n | uniq` ; do \
 	        case "$$F" in \
-	            /*) F="`echo "$$F" | sed "s#^$(abs_top_srcdir)/*#./#"`"; \
+	            /*) F="`echo "$$F" | sed 's#^$(abs_top_srcdir)/*#./#'`"; \
 	                if test x"$${linkroot}" = x"$(abs_builddir)" ; then \
 	                    linkroot="$(abs_top_builddir)" ; \
 	                    linksrcroot="$(abs_top_srcdir)" ; \
@@ -658,7 +903,7 @@ $(abs_top_builddir)/docs/.prep-src-docs: $(PREP_SRC)
 	        D="`dirname "$$F"`" ; \
 	        $(MKDIR_P) "$${linkroot}/$$D" || { rm -f "$@.working" ; exit 1 ; } ; \
 	        if ! test -s "$${linkroot}/$$F" && test -s "$${linksrcroot}/$$F" ; then \
-	            echo "  LN     '$${linksrcroot}/$$F' => '$${linkroot}/$$F' (PWD = '`pwd`')" >&2 ; \
+	            echo "  LN     '$${linksrcroot}/$$F' => '$${linkroot}/$$F' (PWD = '`pwd`')" ; \
 	            ln -fs "$${linksrcroot}/$$F" "$${linkroot}/$$F" || { rm -f "$@.working" ; exit 1 ; } ; \
 	            COUNT="`expr $$COUNT + 1`" ; \
 	        fi ; \
@@ -676,7 +921,7 @@ clean-local:
 	$(AM_V_at)rm -rf *.chunked *.bak tmp
 	$(AM_V_at)for F in $(PREP_SRC) ; do \
 	        case "$$F" in \
-	            /*) F="`echo "$$F" | sed "s#^$(abs_top_srcdir)/*#./#"`"; cd "$(abs_top_builddir)" ;; \
+	            /*) F="`echo "$$F" | sed 's#^$(abs_top_srcdir)/*#./#'`"; cd "$(abs_top_builddir)" ;; \
 	        esac ; \
 	        if test x"$(abs_srcdir)" != x"$(abs_builddir)" ; then \
 	            if test -L "$$F" || test -h "$$F" ; then \
diff --git a/docs/acknowledgements.txt b/docs/acknowledgements.txt
index 77d0fd30ab..875589cc75 100644
--- a/docs/acknowledgements.txt
+++ b/docs/acknowledgements.txt
@@ -71,7 +71,9 @@ UPS manufacturers
 
 [[Eaton]]
 * link:http://powerquality.eaton.com[Eaton], has been the main NUT supporter in
-the past, between 2007 and 2011, continuing MGE UPS SYSTEMS efforts.
+the past, between 2007 and 2011, continuing MGE UPS SYSTEMS efforts. In 2022,
+the Eaton NUT-based companion software bundle sources developed (pre-?)2013-2018
+were contributed and re-licensed to become part of NUT.
 As such, Eaton has been:
   - providing extensive technical documents (Eaton protocols library),
   - providing units to developers of NUT and related projects,
diff --git a/docs/config-notes.txt b/docs/config-notes.txt
index 6451b1c9fb..6fc72d7ddc 100644
--- a/docs/config-notes.txt
+++ b/docs/config-notes.txt
@@ -25,7 +25,7 @@ Generalities
 All configuration files within this package are parsed with a common
 state machine, which means they all can use a number of extras described here.
 
-First, most of the programs use an uppercase word to declare a
+First, most of the programs use an upper-case word to declare a
 configuration directive.  This may be something like MONITOR, NOTIFYCMD,
 or ACCESS.  The case does matter here.  "monitor" won't be recognized.
 
diff --git a/docs/config-prereqs.txt b/docs/config-prereqs.txt
index 600f822952..f52fea02f9 100644
--- a/docs/config-prereqs.txt
+++ b/docs/config-prereqs.txt
@@ -21,9 +21,27 @@ Some of the below are alternatives, e.g. compiler toolkits (gcc vs. clang)
 or SSL implementations (OpenSSL vs Mozilla NSS) -- no problem installing
 both, at a disk space cost.
 
-NOTE: Some NUT branches may need additional or different software versions
+[NOTE]
+======
+Some NUT branches may need additional or different software versions
 that are not yet included into `master` branch dependencies, e.g. the DMF
-(Dynamic Mapping Files) sub-project needs LUA 5.1.
+(Dynamic Mapping Files) sub-project needs LUA 5.1 for build and run-time,
+and some Python modules for build, e.g. using OS packaging or custom call
+to `pip install pycparser`.
+
+In case your system still provides a Python 2.x environment (and for some
+reason you want to use it instead of Python 3.x), but does not anymore
+provide a `pip` nor `pycparser` packages for it, you may need to use an
+external bootstrap first, e.g.:
+
+------
+# Fetch get-pip.py for python 2.7
+:; curl https://bootstrap.pypa.io/pip/2.7/get-pip.py --output get-pip.py
+:; python2 get-pip.py
+:; python2 -m pip --version
+:; python2 -m pip install pycparser
+------
+======
 
 More packages and/or system setup may be needed to actually run NUT with
 all features enabled; chapters below concern just with building it.
@@ -115,6 +133,20 @@ actual package source versions on both Debian 8 "Jessie" and
 Debian 11 "Buster").
 ======
 
+[NOTE]
+.FUN NOTE
+======
+For development on the road (or a native ARM build) you can use the
+link:https://termux.dev/en/[Termux] project on Android. It provides
+a sufficiently Debian-like operating environment for all intents and
+purposes, but you may have to use their `pkg` wrapper instead of `apt`
+tooling directly.
+
+You would need at least a couple of gigabytes available on the internal
+phone storage though, especially if using `ccache` or setting up cross
+builds.
+======
+
 Debian-like package installations commonly start with an update of
 metadata about recently published package revisions:
 
@@ -123,7 +155,7 @@ metadata about recently published package revisions:
 
 :; apt-get install \
     ccache time \
-    git python perl curl \
+    git perl curl \
     make autoconf automake libltdl-dev libtool \
     valgrind \
     cppcheck \
@@ -134,6 +166,10 @@ metadata about recently published package revisions:
 :; apt-get install \
     libtool-bin
 
+# See comments below, python version and package naming depends on distro
+:; apt-get install \
+    python
+
 # NOTE: For python, you may eventually have to specify a variant like this
 # (numbers depending on default or additional packages of your distro):
 #   :; apt-get install python2 python2.7 python-is-python2
@@ -320,13 +356,17 @@ drivers in distro packaging of NUT. Resolution and doc PRs are welcome.
 :; yum install \
     ccache time \
     file \
-    git python perl curl \
+    git perl curl \
     make autoconf automake libtool-ltdl-devel libtool \
     valgrind \
     cppcheck \
     pkgconfig \
     gcc gcc-c++ clang
 
+# See comments below, python version and package naming depends on distro
+:; yum install \
+    python
+
 # NOTE: For python, you may eventually have to specify a variant like this
 # (numbers depending on default or additional packages of your distro):
 #   :; yum install python-2.7.5
@@ -670,13 +710,17 @@ below.
 
 ------
 :; pkg install \
-    git python perl5 curl \
+    git perl5 curl \
     gmake autoconf automake autotools libltdl libtool \
     valgrind \
     cppcheck \
     pkgconf \
     gcc clang
 
+# See comments below, python version and package naming depends on distro
+:; pkg install \
+    python
+
 # NOTE: For python, you may eventually have to specify a variant like this
 # (numbers depending on default or additional packages of your distro):
 #   :; pkg install python2 python27
@@ -699,7 +743,7 @@ below.
 
 :; pkg install \
     cppunit \
-    openssl nss \
+    nss \
     augeas \
     libmodbus \
     neon \
@@ -708,6 +752,15 @@ below.
     freeipmi \
     avahi
 
+# NOTE: At least on FreeBSD 12, system-provided crypto exists and is used
+# by libnetsnmp, libneon, etc. - but is not marked as a package. Conversely,
+# the openssl-1.1.1k (as of this writing) can be installed as a package into
+# /usr/local/lib and then causes linking conflicts. The core system-provided
+# build of openssl does include headers and is useful for NUT build "as is".
+# ONLY INSTALL THIS PACKAGE IF REQUIRED (may get problems to rectify later):
+:; test -e /lib/libcrypto.so -a -e /usr/lib/libssl.so || \
+   pkg install openssl
+
 :; pkg install \
     lua51
 
@@ -789,18 +842,22 @@ default site.
 :; pkg_add sudo bash mc wget rsync
 
 :; pkg_add \
-    git python curl \
+    git curl \
     gmake autoconf automake libltdl libtool \
     valgrind \
     cppcheck \
     pkgconf \
     gcc clang
 
+# See comments below, python version and package naming depends on distro
+:; pkg_add \
+    python
+
 # NOTE: For python, you may eventually have to specify a variant like this
 # (numbers depending on default or additional packages of your distro):
-#   :; pkg_add python-2.7.15p0
+#   :; pkg_add python-2.7.15p0 py-pip
 # and/or:
-#   :; pkg_add python-3.6.6p1
+#   :; pkg_add python-3.6.6p1 py3-pip
 # although you might succeed specifying shorter names and the packager
 # will offer a list of matching variants (as it does for "python" above).
 # NOTE: "perl" is not currently a package, but seemingly part of base OS.
@@ -825,16 +882,23 @@ default site.
     openssl nss \
     augeas \
     libusb1 \
-    neon \
     net-snmp \
     avahi
 
+# For netxml-ups driver the library should suffice; however for nut-scanner
+# you may currently require to add a `libneon.so` symlink (the package seems
+# to only deliver a numbered SO library name), e.g.:
+:; pkg_add neon && \
+   if ! test -s /usr/local/lib/libneon.so ; then
+    ln -s "`cd /usr/local/lib && ls -1 libneon.so.* | sort -n | tail -1`" /usr/local/lib/libneon.so
+   fi
+
 # Select a LUA-5.1 (or possibly 5.2?) version
 :; pkg_add \
     lua
 
 :; pkg_add \
-    dash ksh93
+    bash dash ksh93
 
 :; pkg_add \
     argp-standalone \
@@ -922,12 +986,16 @@ you can work around by `make MKDIRPROG="mkdir -p" install -j 8` for example.
 
 ------
 :; pkgin install \
-    git python27 python39 perl curl \
+    git perl curl \
     make gmake autoconf automake libltdl libtool \
     cppcheck \
     pkgconf \
     gcc7 clang
 
+# See comments below, python version and package naming depends on distro
+:; pkgin install \
+    python27 python39
+
 ;; ( cd /usr/pkg/bin && ( ln -fs python2.7 python2 ; ln -fs python3.9 python3 ) )
 # You can find a list of what is (pre-)installed with:
 #   :; pkgin list | grep -Ei 'perl|python'
@@ -1307,7 +1375,20 @@ for compilers, and Homebrew community packaging for dependencies (including
 `bash` since the system one is too old for `ci_build.sh` script syntax).
 
 See `.travis.yml` and `.circleci/config.yml` for practical details of the
-setup.
+setup, and https://brew.sh if you want to install it on your MacOS system
+(note that its default packaged locations known as `HOMEBREW_PREFIX` differ
+depending on architecture -- see https://docs.brew.sh/Installation for more
+details; find via `brew config | grep HOMEBREW_PREFIX: | awk '{print $2}'`).
+
+NOTE: The quickest pre-configuration for `ci_build.sh` integration with this
+non-default build system would be to add this line into your shell profile:
+----
+eval "$(brew shellenv)"
+----
+
+NOTE: Homebrew is not the only build/packaging system available for MacOS,
+so NUT scripts do not make any assumptions nor try to find a build system
+they were not told about (via `HOMEBREW_PREFIX` in this case).
 
 Currently known dependencies for basic build include:
 ----
@@ -1315,18 +1396,49 @@ Currently known dependencies for basic build include:
 :; HOMEBREW_NO_AUTO_UPDATE=1; export HOMEBREW_NO_AUTO_UPDATE
 
 # Required:
-:; brew install ccache bash libtool pkg-config gd libusb neon net-snmp openssl
+:; brew install ccache bash libtool binutils autoconf automake git m4 \
+        pkg-config aspell asciidoc docbook-xsl cppunit gd \
+        libusb neon net-snmp \
+        nss openssl \
+        libmodbus freeipmi powerman
 ----
 
+NOTE: for `asciidoc`/`a2x` to work, you should `export XML_CATALOG_FILES` with
+the location of packaged resources (`${HOMEBREW_PREFIX}/etc/xml/catalog`).
+On one test system, man page builds spewed warnings like
+`<unknown>:1: SyntaxWarning: invalid escape sequence '\S'`
+but seemed to produce reasonable results otherwise.
+
 Note that ccache is installed in a different location than expected by default
 in the `ci_build.sh` script, so if your system allows to add the symbolic link
-to `/usr/local/opt/ccache/libexec` as `/usr/lib/ccache` -- please do so as the
-easiest way out. Alternatively, to prepare building sessions with `ci_build.sh`
-you can:
+to `/opt/homebrew/opt/ccache/libexec` (`/usr/local/opt/ccache/libexec` on x86)
+as `/usr/lib/ccache` -- please do so as the easiest way out.
+
+Alternatively, to prepare building sessions with `ci_build.sh` you can:
 ----
-:; export CI_CCACHE_SYMLINKDIR="/usr/local/opt/ccache/libexec"
+:; export CI_CCACHE_SYMLINKDIR="/opt/homebrew/opt/ccache/libexec"
+
+### ...or for x86 builders:
+#:; export CI_CCACHE_SYMLINKDIR="/usr/local/opt/ccache/libexec"
 ----
 
+NOTE: For Jenkins agents, also need to `brew install --cask temurin@21`
+for JRE/JDK 21. Java 17 or 21 (an LTS) is required to run Jenkins agents
+after summer 2024.
+
+Note that you would have to create symbolic links to version-numbered names
+of compilers, e.g. `clang-14` and `clang++-14` in both `/usr/local/bin`
+(pointing to `/bin/clang(++)` and in the `ccache` location prepared above
+(pointing to `../bin/ccache`), and repeat that in locations prepared by
+XCode installation such as `/Library/Developer/CommandLineTools/usr/bin/`
+and `/usr/local/Homebrew/Library/Homebrew/shims/mac/super/` just as
+`ln -s clang{,-14} ; ln -s clang++{,-14}`.  Apparently `clang` is the
+only compiler available; various names of `gcc*` are links to the same
+binaries.
+
+WARNING: Take care to *NOT* symlink a `clang-cpp(-14)` which is not a
+name recognized by XCode dispatcher program, so requests to it freeze.
+
 
 Windows builds
 ~~~~~~~~~~~~~~
diff --git a/docs/configure.txt b/docs/configure.txt
index 623e5ec1cc..04655da4da 100644
--- a/docs/configure.txt
+++ b/docs/configure.txt
@@ -255,10 +255,17 @@ Other values understood for this option are listed below:
 * A `--with-doc=no` quietly skips generation of all types of documentation,
   including manpages.
 
-* `--with-doc=skip` is used to configure some of the `make distcheck*`
+* A `--with-doc=skip` is used to configure some of the `make distcheck*`
   scenarios to re-use man page files built and distributed by the main
   build and not waste time on re-generation of those.
 
+* A `--with-doc=dist-auto` allows to use pre-distributed MAN pages if present
+  (should be in "tarball" release archives; should not be among Git-tracked
+  sources; may be left over from earlier builds in same workspace), or build
+  those if we can (the `auto` part). Practically this is implemented in detail
+  only for `--with-doc=man=dist-auto`, as we do not dist HTML and PDF products;
+  it is a placeholder for those to simplify the generic configuration calls.
+
 Multiple documentation format values can be specified, separated with comma.
 Each such value can be suffixed with `=yes` to require building of this one
 documentation format (abort configuration if tools are missing), `=auto` to
@@ -430,6 +437,16 @@ which generated them from data walks, but developers did not rename yet
 to NUT mappings conforming to `docs/nut-names.txt` standards. Production
 driver builds must not include any non-standard names.
 
+	--enable-NUT_STRARG-always (default: auto)
+
+Enable the `NUT_STRARG` macro (to handle `NULL` string printing) even
+if the system libraries seem to safely support this behavior natively?
+This flag should primarily help against overly zealous static analysis
+tools in recent compiler generations.  The `auto` value enables the flag
+for certain compiler versions known to complain about some of our use
+cases -- even though those seem to be false positives.
+
+
 I want it all!
 ~~~~~~~~~~~~~~
 
diff --git a/docs/developers.txt b/docs/developers.txt
index b989da0424..ccddee5be2 100644
--- a/docs/developers.txt
+++ b/docs/developers.txt
@@ -531,6 +531,15 @@ Some supporting maintenance and development is doable with IntelliJ IDEA,
 making some things easier to do than with a simple Notepad, but it does
 not handle C/C++ development as such.
 
+Take note that some IDEs can store their project data in the source root
+directory of a project (such as NUT codebase). While `.gitignore` rules
+can take care of not adding your local configuration into the SCM, these
+locations can be wiped by a careless `git clean -fdX`. You are advised
+to explore configuring your IDE to store project configurations outside
+the source codebase location, or to track such directories as `nbproject`
+or `nb-cache` as a separate Git repository (not necessarily a submodule
+of NUT nor really diligently tracked) to avoid such surprises.
+
 IDE notes on Windows
 ~~~~~~~~~~~~~~~~~~~~
 
@@ -969,6 +978,34 @@ offsets divisible by 4 or 8 (consistently for the whole table):
 #define SOMETHING_WITH_A_VERY_LONG_NAME     255	/* flag comment */
 --------------------------------------------------------------------------------
 
+While at it, we encourage indentation of nested preprocessor macros
+and pragmas, by adding a single space character for each inner level,
+as well as commenting the `#else` and `#endif` parts (especially if
+they are far away from their opening `#if`/`#ifdef`/`#ifndef` statement)
+to help visual navigation in the source code base. Please take care to
+keep the hash `#` character of the preprocessor lines in the left-most
+column, since some implementations of `cpp` parser used for analysis
+default to "traditional" (pre-C89) syntax shared with other languages,
+and then ignore lines which do not start with the hash character (or
+worse, ignore only some of them but not others).
+
+--------------------------------------------------------------------------------
+#ifdef WITH_SSL
+# ifdef WITH_NSS
+	/* some code for NSS */
+# endif	/* WITH_NSS */
+# ifdef WITH_OPENSSL
+#  ifndef WIN32
+	/* some code for OpenSSL on POSIX systems */
+#  else	/* not WIN32 */
+	/* some code for OpenSSL on Windows */
+#  endif	/* not WIN32 */
+# endif	/* WITH_OPENSSL */
+#else	/* not WITH_SSL */
+	/* report that crypto support is not built */
+#endif	/* WITH_SSL */
+--------------------------------------------------------------------------------
+
 If you write something that uses leading spaces, you may get away with
 it in a driver that's relatively secluded.  However, if we have to work
 on that code, expect it to get reformatted according to the above.
@@ -1043,6 +1080,10 @@ To display in a rough example:
 	}
 -------------------------------------------------------------------------------
 
+All this having been said, we do detect and use the support for pragmas
+to quiesce the complaints about such situations, but limit their use to
+processing of certain third-party header files.
+
 Miscellaneous coding style tools
 --------------------------------
 
@@ -1171,6 +1212,9 @@ suspected area and then exit cleanly.  valgrind will tell you if you've
 done anything dodgy like freeing regions twice, reading uninitialized
 memory, or if you've leaked memory anywhere.
 
+See also `scripts/valgrind` in NUT sources for a helper tool and resource
+files to suppress common third-party problems.
+
 For more information, refer to the link:http://valgrind.kde.org[Valgrind]
 project.
 
diff --git a/docs/docinfo.xml.in b/docs/docinfo.xml.in
index 20284705e6..ea0c5fcee0 100644
--- a/docs/docinfo.xml.in
+++ b/docs/docinfo.xml.in
@@ -15,6 +15,17 @@
        with a focus on those changes which impacted documentation.
     -->
   <!-- AUTOINSERT LOCATION -->
+  <revision>
+    <revnumber>2.8.2</revnumber>
+    <date>2024-04-01</date>
+    <authorinitials>JK</authorinitials>
+    <revremark>
+        Some changes to docs and recipes, libnutscan API and functionality.
+        Added nutconf (library and tool). Fixed some regressions and added
+        improvements for certain new device series.
+    </revremark>
+  </revision>
+
   <revision>
     <revnumber>2.8.1</revnumber>
     <date>2023-10-31</date>
diff --git a/docs/documentation.txt b/docs/documentation.txt
index ddc2d1f425..27abb1b76b 100644
--- a/docs/documentation.txt
+++ b/docs/documentation.txt
@@ -23,7 +23,7 @@ ifndef::website[]
 - link:https://www.networkupstools.org/ddl/index.html#_supported_devices[Devices Dumps Library (DDL)]: Provides information on how devices are supported; see also link:https://www.networkupstools.org/stable-hcl.html[the HCL]
 - link:../solaris-usb.html[Notes on NUT monitoring of USB devices in Solaris and related operating systems]
 endif::website[]
-- link:https://github.com/networkupstools/ConfigExamples/releases/latest[NUT Configuration Examples] book maintained by Roger Price
+- link:https://github.com/networkupstools/ConfigExamples/releases/latest/download/ConfigExamples.pdf[NUT Configuration Examples] book maintained by Roger Price
 - link:https://github.com/networkupstools/nut/wiki[NUT GitHub Wiki]
 
 Developer Documentation
@@ -96,7 +96,11 @@ These are general information about UPS, PDU, ATS, PSU and SCD:
 
 These are writeups by users of the software.
 
-- link:http://rogerprice.org/NUT.html[NUT Setup with openSUSE] '(Roger Price)'
+- link:http://rogerprice.org/NUT[NUT Configuration Examples and helper scripts]
+  '(Roger Price)' (sources replicated in NUT GitHub organization as
+  link:https://github.com/networkupstools/ConfigExamples[ConfigExamples],
+  link:https://github.com/networkupstools/TLS-UPSmon[TLS-UPSmon],
+  and link:https://github.com/networkupstools/TLS-Shims[TLS-Shims])
 - link:http://www.dimat.unina2.it/LCS/MonitoraggioUpsNutUbuntu10-eng.htm[Deploying NUT on an Ubuntu 10.04 cluster] '(Stefano Angelone)'
 - link:http://blog.shadypixel.com/monitoring-a-ups-with-nut-on-debian-or-ubuntu-linux[Monitoring a UPS with nut on Debian or Ubuntu Linux] '(Avery Fay)'
 - link:http://linux.developpez.com/cours/upsusb/[Installation et gestion d'un UPS USB en réseau sous linux] '(Olivier Van Hoof, french)'
diff --git a/docs/download.txt b/docs/download.txt
index d4d2ea6110..984e3b7bfa 100644
--- a/docs/download.txt
+++ b/docs/download.txt
@@ -146,7 +146,7 @@ link:https://github.com/networkupstools/nut/wiki/Links-to-distribution-packaging
     * link:https://cgit.freebsd.org/ports/tree/sysutils/nut-devel[FreeBSD package recipe (devel)],
       link:https://cgit.freebsd.org/ports/tree/sysutils/nut[FreeBSD package recipe]
       and link:http://www.FreeBSD.org/cgi/ports.cgi?query=^nut-&amp;stype=name[FreeBSD package overview]
-    * link:cvsweb.netbsd.org/bsdweb.cgi/pkgsrc/sysutils/ups-nut/[NetBSD recipe] and link:http://pkgsrc.se/sysutils/ups-nut[NetBSD package overview]
+    * link:http://cvsweb.netbsd.org/bsdweb.cgi/pkgsrc/sysutils/ups-nut/[NetBSD recipe] and link:https://pkgsrc.se/sysutils/ups-nut[NetBSD package overview]
     * link:http://cvsweb.openbsd.org/cgi-bin/cvsweb/ports/sysutils/nut/[OpenBSD recipe]
     * link:https://github.com/freenas/iocage-ports/tree/master/sysutils/nut[FreeNAS iocage-ports recipe],
       link:http://doc.freenas.org/9.3/freenas_services.html#ups[FreeNAS 9.3 docs on UPS integration]
diff --git a/docs/maintainer-guide.txt b/docs/maintainer-guide.txt
index 51c7561ab4..07af013a5c 100644
--- a/docs/maintainer-guide.txt
+++ b/docs/maintainer-guide.txt
@@ -6,6 +6,10 @@ ____________________
 Introduction
 ============
 
+//////////////////////////////////////////////////////////////////////////////
+NOTE: This file is currently not delivered in tarballs nor spellchecked.
+//////////////////////////////////////////////////////////////////////////////
+
 ...
 
 Mailing lists administration
@@ -88,7 +92,7 @@ MAINTAINER SANDBOX (to be completed and pushed)
 
 * clean up "in-development" bits from files, e.g.:
 ** TODO etc. referring planned future in the `NEWS.adoc` and `UPDATING.adoc`
-   files
+   files - except for the upcoming release
 ** comment away the top-most (auto-resolved) NUT version and build date
    in `docs/docinfo.xml.in` -- DO NOT add (or at least commit) an entry
    for the actual fixed release version and date just yet
@@ -104,20 +108,31 @@ MAINTAINER SANDBOX (to be completed and pushed)
   any recent changes to drivers (including `main.c` and other major impact
   from common code) and sub-drivers (`*-hid.c` for `usbhid-ups`, `*-mib.c`
   for `snmp-ups`, `nutdrv_qx_*` etc.) have been reflected in bumps to their
-  `DRIVER_VERSION` or equivalen macros
+  `DRIVER_VERSION` or equivalent macros
 ** ideally maintained during development, as features are getting merged for
    community testing and future development baseline in the master branch
+** this is the good time to remove the `PLANNED` status from the upcoming
+   release info section title
 * NOTE that the `ChangeLog` file is currently not tracked in SCM
 * update this document: `docs/maintainer-guide.txt` as it inevitably requires
 * commit these finishing touches
 
 * bump the release identification:
+** update the fallback `NUT_DEFAULT_VERSION` in `tools/gitlog2version.sh` to
+   <exact incremented version> (ex: `2.8.0`), and provide the `VERSION_FORCED`
+   and `VERSION_FORCED_SEMVER` files (to same effect but more explicitly and
+   visibly) to be added to the `dist` archive tarball file
+*** Experiment if still needed: update version to <exact incremented version>
+    (ex: 2.8.0) in `configure.ac`, or if the script bump above + git tagging
+    would suffice:
+----
+:; git commit -sm 'configure.ac: update AC_INIT for NUT v2.8.0 release`
+----
 ** add an entry in `docs/docinfo.xml.in` for the actual fixed release version
    and date
 ** revise `.github/workflows/PyNUTClient.yml` for fallback `TAG_NAME` naming
 ** revise `appveyor.yml` for branch naming
 ** revise `scripts/Windows/build-mingw-nut.sh` for fallback value of `VER_OPT`
-** update version to <incremented version> (ex: 2.8.0) in `configure.ac`
 ** commit with a relevant release message, e.g.:
 ----
 :; git commit -sm 'Update versions for release of NUT v2.8.0'
@@ -140,10 +155,11 @@ MAINTAINER SANDBOX (to be completed and pushed)
    make -j 8 spellcheck && \
    make -j 8 distcheck
 ----
-* create a GPG-signed tag v<incremented version> (ex: v2.8.0):
+* create an annotated GPG-signed tag v<incremented version> (ex: `v2.8.0`):
 ----
-:; git tag -sm 'Release NUT v2.8.0'
+:; git tag -asm 'Release NUT v2.8.0' v2.8.0
 ----
+** in case of second thoughts, `git tag -d v2.8.0` and retry later
 ** try to avoid adding signed tags later (ex. v2.8.0-signed) to avoid the
    mess in GitHub release URLs (or do amend that post-factum), for more
    details see e.g. https://github.com/networkupstools/nut/issues/1971
@@ -156,9 +172,17 @@ MAINTAINER SANDBOX (to be completed and pushed)
   then) to store the source tarball, checksum and signature files
 
 * post-release update of the "in-development" codebase:
-** maybe update nut/configure.ac version to <incremented version>.1 (ex: 2.8.0.1)
+** update the fallback `NUT_DEFAULT_VERSION` in `tools/gitlog2version.sh` to
+   <incremented version>.1 (ex: `2.8.0.1`); remove the `VERSION_FORCED`
+   and `VERSION_FORCED_SEMVER` files
+*** maybe update nut/configure.ac version to <incremented version>.1
+    (ex: `2.8.0.1`):
+----
+:; git commit -sm 'configure.ac: bump AC_INIT to development version 2.8.0.1'
+----
 ** `git revert` the commit which cleaned up "in-development" bits above
-** Possibly resolve relevant merge conflicts for the changed context
+** Possibly resolve relevant merge conflicts for the changed context,
+   e.g. the changed "PLANNED" status of the now-issued release info
 
 * push commits and tag
 
@@ -172,15 +196,24 @@ MAINTAINER SANDBOX (to be completed and pushed)
    NOTE: for `nut` submodule be sure to refer to the tagged commit, not to
    the subsequent "in-development" codebase.
 ** in `source` submodule add a copy of tarball, checksum and hash files for
-   download
+   download: `make dist{,-hash,-sig}`
+*** for a `new-X.Y.Z.txt` file use the `NEWS.adoc` with a stripped title
+    (see existing files)
 ** `git tag` the website release
-** generate and publish a "historic" sub-site snapshot (currently manually)
+** generate and publish a "historic" sub-site snapshot (currently manually,
+   check comments in nut-website's `ci_build.sh` script and/or its README file)
 ** update `nut` submodule to current commit ("in-development" codebase), and
    the `historic/index.txt` to refer to the snapshot for reference (users of
    specific-version packages)
 ** generate and publish the usual website revision (by CI or manually)
+** Note that it may be needed to manually copy the new tarball-related files,
+   `new-X.Y.Z.txt`, change log, and maintainer keys (if updated), into the
+   rendered website repository, even if using the CI scripted publication.
 
-* check that the website renders properly
+* check that the website renders properly (a few minutes after publication)
+** re-check the tarball signature according to current `security.txt` document
+   on an empty VM/container/chroot/user-home setup, to make sure that the GPG
+   instructions fit the reality (needed maintainer keys are published, etc.)
 
 * draft and publish a GitHub release based on the signed tag
 ** attach the same copy of tarball, checksum and hash files as for nut-website
@@ -195,4 +228,13 @@ MAINTAINER SANDBOX (to be completed and pushed)
 
 * announce on mailing list, IRC, etc.
 
+* update https://en.wikipedia.org/wiki/Network_UPS_Tools
+
+* create a GitHub issue label for the new release, e.g. at
+  https://github.com/networkupstools/nut/labels?q=impact :
+----
+impacts-release-2.8.0
+Issues reported against NUT release 2.8.0 (maybe vanilla or with minor packaging tweaks)
+----
+
 //////////////////////////////////////////////////////////////////////////////
diff --git a/docs/man/Makefile.am b/docs/man/Makefile.am
index 2931bc5252..a7b5d3781a 100644
--- a/docs/man/Makefile.am
+++ b/docs/man/Makefile.am
@@ -22,6 +22,8 @@ EGREP = grep -E
 
 all:
 
+all-am-local all-local: $(abs_top_builddir)/docs/man/.prep-src-docs
+
 # Base configuration and client manpages, always installed
 SRC_CONF_PAGES = \
 	nut.conf.txt \
@@ -85,6 +87,13 @@ MAN_CLIENT_PAGES = \
 	upssched.8
 endif WITH_MANS
 
+if HAVE_WINDOWS
+SRC_CLIENT_PAGES += nut.exe.txt
+if WITH_MANS
+MAN_CLIENT_PAGES += nut.exe.8
+endif WITH_MANS
+endif HAVE_WINDOWS
+
 man8_MANS = $(MAN_CLIENT_PAGES)
 
 HTML_CLIENT_MANS = \
@@ -100,6 +109,10 @@ HTML_CLIENT_MANS = \
 	upsrw.html \
 	upssched.html
 
+if HAVE_WINDOWS
+HTML_CLIENT_MANS += nut.exe.html
+endif HAVE_WINDOWS
+
 SRC_TOOL_PAGES = nut-scanner.txt nut-recorder.txt nutconf.txt
 
 if WITH_MANS
@@ -185,6 +198,12 @@ SRC_DEV_PAGES = \
 	nutscan_display_ups_conf_with_sanity_check.txt \
 	nutscan_display_ups_conf.txt \
 	nutscan_display_parsable.txt \
+	nutscan_init_ip_ranges.txt \
+	nutscan_free_ip_ranges.txt \
+	nutscan_stringify_ip_ranges.txt \
+	nutscan_add_ip_range.txt \
+	nutscan_ip_ranges_iter_init.txt \
+	nutscan_ip_ranges_iter_inc.txt \
 	nutscan_cidr_to_ip.txt \
 	nutscan_new_device.txt \
 	nutscan_free_device.txt \
@@ -303,6 +322,12 @@ MAN3_DEV_PAGES = \
 	nutscan_display_ups_conf_with_sanity_check.3 \
 	nutscan_display_ups_conf.3 \
 	nutscan_display_parsable.3 \
+	nutscan_init_ip_ranges.3 \
+	nutscan_free_ip_ranges.3 \
+	nutscan_stringify_ip_ranges.3 \
+	nutscan_add_ip_range.3 \
+	nutscan_ip_ranges_iter_init.3 \
+	nutscan_ip_ranges_iter_inc.3 \
 	nutscan_cidr_to_ip.3 \
 	nutscan_new_device.3 \
 	nutscan_free_device.3 \
@@ -312,13 +337,25 @@ MAN3_DEV_PAGES = \
 	nutscan_get_serial_ports_list.3 \
 	nutscan_init.3
 
+# Alias page for one text describing two commands:
 upscli_readline_timeout.3: upscli_readline.3
 	touch $@
 
 upscli_sendline_timeout.3: upscli_sendline.3
 	touch $@
 
-# Alias page for one text describing two commands:
+nutscan_scan_ip_range_snmp.3: nutscan_scan_snmp.3
+	touch $@
+
+nutscan_scan_ip_range_xml_http.3: nutscan_scan_xml_http_range.3
+	touch $@
+
+nutscan_scan_ip_range_nut.3: nutscan_scan_nut.3
+	touch $@
+
+nutscan_scan_ip_range_ipmi.3: nutscan_scan_ipmi.3
+	touch $@
+
 nutscan_add_commented_option_to_device.3: nutscan_add_option_to_device.3
 	touch $@
 
@@ -378,6 +415,12 @@ HTML_DEV_MANS = \
 	nutscan_display_ups_conf_with_sanity_check.html \
 	nutscan_display_ups_conf.html \
 	nutscan_display_parsable.html \
+	nutscan_init_ip_ranges.html \
+	nutscan_free_ip_ranges.html \
+	nutscan_stringify_ip_ranges.html \
+	nutscan_add_ip_range.html \
+	nutscan_ip_ranges_iter_init.html \
+	nutscan_ip_ranges_iter_inc.html \
 	nutscan_cidr_to_ip.html \
 	nutscan_new_device.html \
 	nutscan_free_device.html \
@@ -392,8 +435,32 @@ HTML_DEV_MANS = \
 # Can't make this work on all make implementations at once, so disabled for now
 # Anyway it would be the same man-like page for several functions
 HTML_DEV_MANS_FICTION = \
+	upscli_readline_timeout.html \
+	upscli_sendline_timeout.html \
+	nutscan_scan_ip_range_snmp.html \
+	nutscan_scan_ip_range_xml_http.html \
+	nutscan_scan_ip_range_nut.html \
+	nutscan_scan_ip_range_ipmi.html \
 	nutscan_add_commented_option_to_device.html
 
+upscli_readline_timeout.html: upscli_readline.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
+upscli_sendline_timeout.html: upscli_sendline.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
+nutscan_scan_ip_range_snmp.html: nutscan_scan_snmp.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
+nutscan_scan_ip_range_xml_http.html: nutscan_scan_xml_http_range.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
+nutscan_scan_ip_range_nut.html: nutscan_scan_nut.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
+nutscan_scan_ip_range_ipmi.html: nutscan_scan_ipmi.html
+	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
+
 nutscan_add_commented_option_to_device.html: nutscan_add_option_to_device.html
 	test -n "$?" -a -s "$@" && rm -f $@ && ln -s $? $@
 
@@ -417,9 +484,11 @@ SRC_SERIAL_PAGES = \
 	bestuferrups.txt	\
 	bestups.txt 	\
 	bestfcom.txt	\
+	bicker_ser.txt	\
 	blazer-common.txt	\
 	blazer_ser.txt	\
-	clone.txt \
+	clone.txt	\
+	clone-outlet.txt	\
 	dummy-ups.txt	\
 	etapro.txt	\
 	everups.txt	\
@@ -464,8 +533,10 @@ MAN_SERIAL_PAGES = \
 	bestuferrups.8	\
 	bestups.8 	\
 	bestfcom.8	\
+	bicker_ser.8	\
 	blazer_ser.8	\
-	clone.8 \
+	clone.8	\
+	clone-outlet.8	\
 	dummy-ups.8	\
 	etapro.8	\
 	everups.8	\
@@ -513,8 +584,10 @@ HTML_SERIAL_MANS = \
 	bestuferrups.html	\
 	bestups.html 	\
 	bestfcom.html	\
+	bicker_ser.html	\
 	blazer_ser.html	\
-	clone.html \
+	clone.html	\
+	clone-outlet.html	\
 	dummy-ups.html	\
 	etapro.html	\
 	everups.html	\
@@ -709,17 +782,17 @@ HTML_MODBUS_MANS = phoenixcontact_modbus.html \
 endif ! SOME_DRIVERS
 
 # (--with-linux_i2c)
-SRC_LINUX_I2C_PAGES = asem.txt pijuice.txt
+SRC_LINUX_I2C_PAGES = asem.txt pijuice.txt hwmon_ina219.txt
 if ! SOME_DRIVERS
 if WITH_MANS
-MAN_LINUX_I2C_PAGES = asem.8 pijuice.8
+MAN_LINUX_I2C_PAGES = asem.8 pijuice.8 hwmon_ina219.8
 endif WITH_MANS
 
 if WITH_LINUX_I2C
 man8_MANS += $(MAN_LINUX_I2C_PAGES)
 endif WITH_LINUX_I2C
 
-HTML_LINUX_I2C_MANS = asem.html pijuice.html
+HTML_LINUX_I2C_MANS = asem.html pijuice.html hwmon_ina219.html
 endif ! SOME_DRIVERS
 
 # (--with-gpio)
@@ -832,6 +905,16 @@ HTML_MANS = \
 	$(HTML_LINUX_I2C_MANS) \
 	$(HTML_GPIO_MANS)
 
+# htmlmandir is set by autoconf/automake
+htmlman_DATA =
+if WITH_HTML_SINGLE
+htmlman_DATA += $(HTML_MANS)
+else !WITH_HTML_SINGLE
+if WITH_HTML_CHUNKED
+htmlman_DATA += $(HTML_MANS)
+endif WITH_HTML_CHUNKED
+endif !WITH_HTML_SINGLE
+
 # Note: target documents, except nutupsdrv.txt itself, start the
 # list of drivers with `- linkman:nutupsdrv[8]` entry
 # To regenerate these files, do `make distclean` first
@@ -950,7 +1033,7 @@ CLEANFILES = *-spellchecked .prep-src-docs *-prepped
 
 SUFFIXES = .txt-prepped .txt .html .1 .3 .5 .8
 
-# For builds with allowed installation of prebuild man pages, check that
+# For builds with allowed installation of prebuilt man pages, check that
 # they exist in sources (make would pull them automatically as a fallback
 # from failed lookup in build products). For builds that require rebuild
 # of man pages, abort with error if build product is missing.
@@ -1123,7 +1206,7 @@ endif !HAVE_ASCIIDOC
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/docs/man/apc_modbus.txt b/docs/man/apc_modbus.txt
index 07cac400f6..4deb74b4e1 100644
--- a/docs/man/apc_modbus.txt
+++ b/docs/man/apc_modbus.txt
@@ -83,6 +83,66 @@ Set the Modbus slave id. The default slave id is 1.
 Set the Modbus response timeout. The default timeout is set by libmodbus. It can
 be good to set a higher timeout on TCP connections with high latency.
 
+BUGS
+----
+
+This driver relies on advanced features of `libmodbus` to talk Modbus protocol
+over USB specifically (Serial and TCP are part of common library codebase).
+At the time of this writing, the common library project is just expecting a
+merge of the pull request with this ability.
+
+For the time being, if your OS distribution does not ship the required feature
+set, you may have to build your own `libmodbus` and subsequently (re-)build NUT
+against this library, as detailed in the NUT GitHub Wiki at
+https://github.com/networkupstools/nut/wiki/APC-UPS-with-Modbus-protocol
+
+The short sequence may be like follows:
+------
+cd ~/
+git clone -b rtu_usb https://github.com/networkupstools/libmodbus
+cd libmodbus
+./autogen.sh
+./configure --with-libusb --prefix=/path/to/prefix
+make install
+------
+
+[NOTE]
+======
+* you may need to `make && sudo make install` if you want to place this library
+  files' variant into a system path (like `--prefix=/usr/local/ups` to match
+  NUT defaults -- this activity would need privilege elevation via `sudo`),
+  and not into your home directory or some `/tmp` location.
+* conversely, you may want to
+  `./configure --with-libusb --enable-static --disable-shared --prefix=/path/to/prefix`
+  and only build and install a static `libmodbus.a` (can well be installed into
+  `/tmp` or similarly short-lived location), so that the customized Modbus+USB
+  logic gets built directly into `apc_modbus` binary program and there would be
+  no potential run-time conflict with a dynamic library file available elsewhere
+  in the system.
+======
+
+------
+cd ~/
+git clone https://github.com/networkupstools/nut
+cd nut
+./autogen.sh
+./configure --with-drivers=apc_modbus --with-usb --with-modbus \
+   --with-modbus-includes=-I/path/to/prefix/include/modbus \
+   --with-modbus-libs="-L/path/to/prefix/lib -lmodbus"
+make
+------
+
+[NOTE]
+======
+* Other NUT `configure` options may be needed for proper behavior, such as
+`--prefix`, `--with-sysconfdir`, `--with-user` and `--with-group` to match
+your packaged or otherwise preceding NUT installation.
+======
+
+The `./configure --enable-inplace-runtime` may be a good start to inherit
+build configuration from an existing NUT deployment, as further detailed at
+https://github.com/networkupstools/nut/wiki/Building-NUT-for-in%E2%80%90place-upgrades-or-non%E2%80%90disruptive-tests
+
 AUTHORS
 -------
 
diff --git a/docs/man/bicker_ser.txt b/docs/man/bicker_ser.txt
new file mode 100644
index 0000000000..bebecceef7
--- /dev/null
+++ b/docs/man/bicker_ser.txt
@@ -0,0 +1,123 @@
+BICKER_SER(8)
+=============
+
+NAME
+----
+
+bicker_ser - Driver for Bicker DC UPS via serial port connections
+
+SYNOPSIS
+--------
+
+*bicker_ser* -h
+
+*bicker_ser* -a 'UPS_NAME' ['OPTIONS']
+
+NOTE: This man page only documents the hardware-specific features of the
+*bicker_ser* driver.  For information about the core driver, see
+linkman:nutupsdrv[8].
+
+SUPPORTED HARDWARE
+------------------
+
+*bicker_ser* supports all Bicker UPSes shipped with the PSZ-1053 extension
+module such as UPSIC-1205, UPSIC-2403, DC2412-UPS and DC2412-UPS-LD.
+
+CABLING
+-------
+
+The needed cable is a standard pin-to-pin serial cable with pins 2, 3 and 5
+(on DB9 connector) connected.
+
+EXTRA ARGUMENTS
+---------------
+
+This driver supports no extra arguments from linkman:ups.conf[5].
+
+VARIABLES
+---------
+
+Depending on the type of your UPS unit, some of the following variables may
+be changed with linkman:upsrw[8]. If the driver can't read a variable from the
+UPS, it will not be made available. Whenever not explicitly stated, any variable
+can be disabled, in which case the action it performs will not be executed. To
+disable a variable, set it to an empty value.
+
+*ups.delay.shutdown* (in seconds, default disabled)::
+If activated and the UPS is in battery mode and the set time has expired, the
+output will be disabled, and the UPS and energy storage will be disconnected.
+
+*ups.delay.start* (in seconds, default disabled)::
+If activated and a restart condition switches the UPS output off and on again,
+the set time is the delay between switching on and off. The time should cause a
+defined off time so that capacities in the application can be discharged.
+
+*battery.charge.restart* (in percent, default disabled)::
+If activated and the UPS is off or restarts, the UPS output will not be released
+until the energy storage device has the set charge state. The energy storage
+device is charged in the meantime.
+
+*battery.charge.low* (in percent, default `20`)::
+If activated and the UPS is in battery mode and the battery level drops below
+the set value, a shutdown command via relay event is signaled.
+
+*experimental.output.current.low* (in mA, default `200`)::
+If activated and the UPS is in battery mode and the current drops below the set
+value, the output of the UPS will shut down and disconnect the energy storage to
+prevent self-discharge.
+
+*experimental.ups.delay.shutdown.signal* (in seconds, default disabled)::
+If activated and the UPS is in battery mode and the set time has elapsed, a
+shutdown command via relay event is signaled.
+
+*experimental.ups.delay.shutdown.signal.masked* (in seconds, default disabled)::
+If activated and the UPS is in battery mode and the signal at the IN-1 input is
+high and the set time has expired, a shutdown command via relay event is
+signaled.
+
+*experimental.battery.charge.low.empty* (in percent, default `20`)::
+This parameter stores the threshold value for the "Battery Empty" signal.
+Currently this setting is only valid for relay signaling. Cannot be disabled.
+
+*experimental.ups.relay.mode* (default `0x01`)::
+This parameter controls the behavior of the relay in case of different events.
+Cannot be disabled.
++
+Available relay modes:
+[horizontal]
+`0x01`::: On power fail (normally closed)
+`0x02`::: On power fail (normally opened)
+`0x03`::: Shutdown impulse (1 second)
+`0x04`::: Battery low signal (normally closed)
+`0x05`::: Battery defect signal (normally closed)
+
+INSTANT COMMANDS
+----------------
+
+*shutdown.return*::
+Turn off the load and return when power is back.
+
+KNOWN ISSUES AND BUGS
+---------------------
+
+*ups.delay.shutdown is not honored*::
+Although that delay is properly set when sending the shutdown command, it seems
+some UPS ignore it and use a fixed 2 seconds delay instead.
+
+AUTHOR
+------
+
+Nicola Fontana <ntd@entidi.it>
+
+SEE ALSO
+--------
+
+The core driver:
+~~~~~~~~~~~~~~~~
+
+linkman:nutupsdrv[8]
+
+Internet resources:
+~~~~~~~~~~~~~~~~~~~
+
+The NUT (Network UPS Tools) home page: https://www.networkupstools.org/
diff --git a/docs/man/clone-outlet.txt b/docs/man/clone-outlet.txt
new file mode 100644
index 0000000000..b26d778f34
--- /dev/null
+++ b/docs/man/clone-outlet.txt
@@ -0,0 +1,197 @@
+CLONE-OUTLET(8)
+===============
+
+NAME
+----
+
+clone-outlet - clone an UPS, treating its outlet as if it were an UPS (monitoring only)
+
+SYNOPSIS
+--------
+
+*clone-outlet* -h
+
+*clone-outlet* -a 'UPS_NAME' ['OPTIONS']
+
+NOTE: This man page only documents the specific features of the
+clone-outlet driver.  For information about the core driver, see
+linkman:nutupsdrv[8].
+
+DESCRIPTION
+-----------
+
+This driver, which sits on top of another driver socket, allows users to group
+clients to a particular outlet of a device and deal with this output as if it
+were a normal UPS.  Unlike the linkman:clone[8] driver or linkman:dummy-ups[8]
+in repeater mode, this driver represents a read-only device for monitoring and
+shutdowns (it does not accept setting any values or sending instant commands
+during run time).
+
+Unlike linkman:dummy-ups[8], this driver does not require a running `upsd`
+data server nor use the networked NUT protocol to talk to the "real" driver
+(which may be remote in case of `dummy-ups` repeater mode).
+
+This driver does not create a completely new virtual device, but replaces or
+extends some of the original readings reported by the "real" driver using
+information from the specified outlet, and relays all other readings as they
+were.
+
+Remote clients like `upsmon` can `MONITOR` the device entry presented by the
+data server with this driver (and the "real" driver) running and published.
+
+A larger deployment with one or more lower-priority devices collected on a
+manageable outlet of an UPS or ePDU would likely see several drivers set
+up on the system actually capable of interactions with the UPS and running
+the NUT data server linkman:upsd[8] (and likely powered by another outlet):
+
+* a "real" driver talking to the UPS;
+* a `clone` driver talking to the "real" driver and issuing outlet power-off
+  (or power-cycle) based on relatively high thresholds for remaining battery
+  charge and/or runtime of the actual UPS (or explicit instant commands),
+  with such operations first setting the respective timers for the outlet
+  on the "real" driver, and the "FSD" flag among states of the virtual UPS
+  status;
+* possibly a `clone-outlet` driver which is read-only and interprets the
+  outlet timer values as triggers for "FSD" or "OFF" flags reported among
+  states of the virtual UPS status.
+
+With this approach, the lower-priority systems collected on such outlet
+would run the NUT linkman:upsmon[8] client to `MONITOR` the virtual UPS
+presented by the read-only `clone-outlet` driver and shut down as soon as
+the "FSD" flag is raised (fairly early, based on charge and/or runtime
+thresholds configured for that driver) allowing the higher-priority devices
+(likely including the NUT server) to enjoy a longer on-battery life.
+
+The `clone` driver responsible for outlet power state changes would not
+normally be monitored directly (e.g. to avoid unfortunate direct shutdown
+requests from those clients), although it can be (instead of `clone-outlet`)
+in sufficiently trusted networks.
+
+EXTRA ARGUMENTS
+---------------
+
+This driver supports the following settings:
+
+*port*='drivername-devicename'::
+Required. The standard NUT driver `port` setting, here it provides the name
+of the local Unix socket (or named Windows pipe) for connection to the "real"
+driver.
+
+*prefix*='outlet.N'::
+Required. Specify the outlet prefix as known on the original driver.
+The subset of data points reported by the "real" UPS driver for the actual device
+on this prefix would be reported as data points of the virtual UPS maintained by
+this driver.
+
+IMPLEMENTATION
+--------------
+
+The port specification in the linkman:ups.conf[5] should reference the
+local driver socket (or Windows named pipe) that the "real" UPS driver
+is using. For example:
+
+------
+  [realups]
+     driver = usbhid-ups
+     port = auto
+
+  [clone-outlet-1]
+     driver = clone-outlet
+     port = usbhid-ups-realups
+     prefix = outlet.1
+     desc = "Outlet 1 of the Real UPS"
+     [...]
+------
+
+The driver internally interprets "real" driver's information about shutdown
+delay and shutdown timer, whole UPS status and this outlet's status, and
+relays other data points as they were.
+
+If the outlet supports and reports a delayed power-off, the virtual UPS would
+issue an FSD via `ups.status` for its clients to shut down safely.
+
+In more detail:
+
+Given the (required) `prefix` value such as `outlet.1`, the driver would
+specifically keep track of `<prefix>.status`, `<prefix>.delay.shutdown`,
+and `<prefix>.timer.shutdown` data points reported by the "real" driver.
+Numeric values of the `*.shutdown` readings would be noted by this driver,
+and the boolean outlet status ("off" or otherwise) will be remembered.
+These values will also be re-published by this driver "as is".
+
+The `ups.status` from the "real" driver would be remembered, but not
+re-published by this driver immediately. Instead, it would be published
+during regular "update info" loop cycles either:
+
+* with the "OFF" state added (if `<prefix>.status` indicates the outlet
+  is "off"),
+* or with the "FSD" state prepended (if `<prefix>.timer.shutdown` is
+  non-negative and does not exceed the `<prefix>.delay.shutdown` value),
+* or "as is" if the outlet power state is "not critical".
+
+
+IMPORTANT
+---------
+
+Unlike a real UPS, you should *not* configure a upsmon primary mode for this
+driver.  When a upsmon primary sees the OB LB flags and tells the upsd server
+it is OK to initiate the shutdown sequence, the server will latch the FSD
+status and it will not be possible to restart the systems connected without
+restarting the upsd server.
+
+This will be a problem if the power returns after the clone UPS initiated
+the shutdown sequence on it's outlet, but returns before the real UPS begins
+shutting down. The solution is in the clone driver, that will insert the
+FSD flag if needed without the help of a upsmon primary.
+
+CAVEATS
+-------
+
+The clone UPS will follow the status on the real UPS driver.  You can only
+make the clone UPS shutdown earlier than the real UPS driver, not later.
+If the real UPS driver initiates a shutdown, the clone-outlet UPS driver
+will immediately follow.
+
+Be aware that the commands to shutdown/restart an outlet on the real UPS
+drivers are not affected, so if you tell the real UPS driver to shutdown
+the outlet of the clone UPS driver immediately, your clients will lose
+power without warning. A delayed outlet power-off should propagate as FSD,
+and the delay should be sufficiently long to allow for client shutdowns.
+
+If you use service management frameworks like systemd or SMF to manage the
+dependencies between driver instances and other units, then you may have
+to set up special dependencies (e.g. with systemd "drop-in" snippet files)
+to queue your `clone` drivers to start after the "real" device drivers.
+
+//////////////////////////////////////
+TODO later: declare the driver as "optional", see
+https://github.com/networkupstools/nut/issues/1389
+//////////////////////////////////////
+
+AUTHOR
+------
+
+Arjen de Korte <adkorte-guest@alioth.debian.org>
+
+SEE ALSO
+--------
+
+linkman:upscmd[1],
+linkman:upsrw[1],
+linkman:ups.conf[5],
+linkman:clone[8],
+linkman:nutupsdrv[8]
+
+Dummy driver:
+~~~~~~~~~~~~~
+
+The "repeater" mode of 'dummy-ups' driver is in some ways similar to the
+'clone' and 'clone-outlet' drivers, by relaying information from a locally
+or remotely running "real" device driver (and NUT data server).
+
+linkman:dummy-ups[8]
+
+Internet Resources:
+~~~~~~~~~~~~~~~~~~~
+
+The NUT (Network UPS Tools) home page: https://www.networkupstools.org/
diff --git a/docs/man/clone.txt b/docs/man/clone.txt
index d5ee2e4a8c..bd27128057 100644
--- a/docs/man/clone.txt
+++ b/docs/man/clone.txt
@@ -4,7 +4,7 @@ CLONE(8)
 NAME
 ----
 
-clone - UPS driver clone
+clone - clone an UPS, treating its outlet as if it were an UPS (with shutdown INSTCMD support)
 
 SYNOPSIS
 --------
@@ -22,13 +22,61 @@ DESCRIPTION
 
 This driver, which sits on top of another driver socket, allows users to group
 clients to a particular outlet of a device and deal with this output as if it
-was a normal UPS.
+were a normal UPS.  Unlike the linkman:clone-outlet[8] driver, this driver
+represents a manageable device for that can be used both for monitoring and
+for client computer and UPS/ePDU outlet shutdowns (it supports sending
+relevant instant commands during run time).
+
+Unlike linkman:dummy-ups[8], this driver does not require a running `upsd`
+data server nor use the networked NUT protocol to talk to the "real" driver
+(which may be remote in case of `dummy-ups` repeater mode).
+
+This driver does not create a completely new virtual device, but replaces or
+extends some of the original readings reported by the "real" driver using
+information from the specified outlet, and relays all other readings as they
+were.
+
+Remote clients like `upsmon` can `MONITOR` the device entry presented by the
+data server with this driver (and the "real" driver) running and published.
+
+A larger deployment with one or more lower-priority devices collected on a
+manageable outlet of an UPS or ePDU would likely see several drivers set
+up on the system actually capable of interactions with the UPS and running
+the NUT data server linkman:upsd[8] (and likely powered by another outlet):
+
+* a "real" driver talking to the UPS;
+* a `clone` driver talking to the "real" driver and issuing outlet power-off
+  (or power-cycle) based on relatively high thresholds for remaining battery
+  charge and/or runtime of the actual UPS (or explicit instant commands),
+  with such operations first setting the respective timers for the outlet
+  on the "real" driver, and the "FSD" flag among states of the virtual UPS
+  status;
+* possibly a `clone-outlet` driver which is read-only and interprets the
+  outlet timer values as triggers for "FSD" or "OFF" flags reported among
+  states of the virtual UPS status.
+
+With this approach, the lower-priority systems collected on such outlet
+would run the NUT linkman:upsmon[8] client to `MONITOR` the virtual UPS
+presented by the read-only `clone-outlet` driver and shut down as soon as
+the "FSD" flag is raised (fairly early, based on charge and/or runtime
+thresholds configured for that driver) allowing the higher-priority devices
+(likely including the NUT server) to enjoy a longer on-battery life.
+
+The `clone` driver responsible for outlet power state changes would not
+normally be monitored directly (e.g. to avoid unfortunate direct shutdown
+requests from those clients), although it can be (instead of `clone-outlet`)
+in sufficiently trusted networks.
 
 EXTRA ARGUMENTS
 ---------------
 
 This driver supports the following settings:
 
+*port*='drivername-devicename'::
+Required. The standard NUT driver `port` setting, here it provides the name
+of the local Unix socket (or named Windows pipe) for connection to the "real"
+driver.
+
 *load.off*='command'::
 Recommended.  Set the command on the "real" UPS driver that will be used to
 switch off the outlet.  You need both *load.off* and *load.on* in
@@ -67,8 +115,9 @@ Set the remaining battery runtime when the clone UPS switches to LB
 IMPLEMENTATION
 --------------
 
-The port specification in the linkman:ups.conf[5] reference the driver
-socket that the "real" UPS driver is using. For example:
+The port specification in the linkman:ups.conf[5] should reference the
+local driver socket (or Windows named pipe) that the "real" UPS driver
+is using. For example:
 
 ------
   [realups]
@@ -81,9 +130,44 @@ socket that the "real" UPS driver is using. For example:
      load.on = outlet.1.load.on
      load.off = outlet.1.load.off
      load.status = outlet.1.status
+     desc = "Outlet 1 of the Real UPS"
      [...]
 ------
 
+This driver supports instant commands to initiate a forced shutdown for
+`upsmon` or similar clients which `MONITOR` this virtual UPS device, if
+the outlet status is currently 'on' and no other shutdown was initiated
+yet (setting the virtual UPS shutdown delay timer to `offdelay` and
+issuing an FSD via `ups.status`):
+
+* `shutdown.return` -- power the outlet back on after `ondelay`;
+* `shutdown.stayoff` -- keep the outlet 'off'.
+
+Such commands are propagated to the "real" driver using the NUT socket
+protocol (using command names specified in the `load.off` and `load.on`
+driver configuration options), if the shutdown or start timers are set
+at the moment, or if the "real" device is not "online" and its known
+battery charge or runtime are below the configured "low" thresholds.
+
+The outlet status is determined using the name specified by the
+`load.status` driver option if set, or is just assumed by latest
+completed shutdown/start operation (using unknown outlet number).
+
+The driver does not support a common NUT device shutdown operation as
+such (`clone -k` just prints an error and bails out).
+
+This driver also supports setting certain NUT variables at run-time:
+
+* `battery.charge.low` -- see `mincharge` in driver options;
+* `battery.runtime.low` -- see `minruntime` in driver options.
+
+Compared to the "real" driver's readings, this driver also adds
+(or overrides) the following data points: `ups.delay.shutdown`,
+`ups.delay.start`, `ups.timer.shutdown` and `ups.timer.start`.
+It keeps track of "real" driver's values of `battery.charge` and
+`battery.runtime` (actual current readings) to decide on automated
+outlet shutdown later on.
+
 IMPORTANT
 ---------
 
@@ -132,14 +216,15 @@ SEE ALSO
 linkman:upscmd[1],
 linkman:upsrw[1],
 linkman:ups.conf[5],
+linkman:clone-outlet[8],
 linkman:nutupsdrv[8]
 
 Dummy driver:
 ~~~~~~~~~~~~~
 
 The "repeater" mode of 'dummy-ups' driver is in some ways similar to the
-'clone' driver, by relaying information from a locally or remotely running
-"real" device driver (and NUT data server).
+'clone' and 'clone-outlet' drivers, by relaying information from a locally
+or remotely running "real" device driver (and NUT data server).
 
 linkman:dummy-ups[8]
 
diff --git a/docs/man/dummy-ups.txt b/docs/man/dummy-ups.txt
index b45de7d85d..d51f42e56e 100644
--- a/docs/man/dummy-ups.txt
+++ b/docs/man/dummy-ups.txt
@@ -282,11 +282,16 @@ Clone driver:
 ~~~~~~~~~~~~~
 
 The "repeater" mode of 'dummy-ups' driver is in some ways similar to the
-'clone' driver, which sits on top of another driver socket, and allows
-users to group clients to a particular outlet of a device and deal with
-this output as if it were a normal UPS.
-
-linkman:clone[8]
+'clone' and 'clone-outlet' drivers, which sit on top of another driver
+socket (or named Windows pipe) locally, and allow users to group clients
+to a particular outlet of a device and deal with this output as if it
+were a normal UPS.  Notably, in this mode the 'dummy-ups' driver is a
+client to the networked NUT protocol and can relay information of local
+or remotely served devices, and requires a running NUT data server 'upsd'
+to represent the "real" device for this to work.
+
+linkman:clone[8],
+linkman:clone-outlet[8]
 
 Internet Resources:
 ~~~~~~~~~~~~~~~~~~~
diff --git a/docs/man/hosts.conf.txt b/docs/man/hosts.conf.txt
index 1bf23da3c2..9c82cd016c 100644
--- a/docs/man/hosts.conf.txt
+++ b/docs/man/hosts.conf.txt
@@ -14,6 +14,12 @@ linkman:upsimage.cgi[8]) use this file to determine if they are allowed to
 talk to a host.  This keeps random visitors from using your web server
 to annoy others by creating outgoing connections.
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
+
 DIRECTIVES
 ----------
 
diff --git a/docs/man/huawei-ups2000.txt b/docs/man/huawei-ups2000.txt
index fadd11c39c..0cbe179a9f 100644
--- a/docs/man/huawei-ups2000.txt
+++ b/docs/man/huawei-ups2000.txt
@@ -31,9 +31,13 @@ on Linux 5.12 and newer kernels, but there are exceptions, read the section
 *Cabling* carefully).
 
 The UPS2000 series has two variants: UPS2000-A with a tower chassis,
-and UPS2000-G with a rack-mount chassis. Both should be equally supported,
-but more testers are needed.
-Currently, it has been tested on the following models.
+and UPS2000-G with a rack-mount chassis. Within these two variants,
+there are also two sub-variants: a standard runtime model powered by
+an internal battery pack denoted by an "S" suffix, and a long runtime
+model powered by an external battery pack denoted by an "L" suffix.
+
+All of these models should be equally supported, but more testers are
+needed. Currently, it has been tested on the following models.
 
 * UPS2000-A-1KTTS (firmware: UPS2000A, V2R1C1SPC40, P1.0-D1.0)
 * UPS2000-A-1KTTS (firmware: UPS2000A, V2R1C1SPC50, P1.0-D1.0)
@@ -42,6 +46,7 @@ Currently, it has been tested on the following models.
 * UPS2000-G-1KRTS (firmware: UPS2000G, V2R1C1SPC50, P1.0-D1.0)
 * UPS2000-G-3KRTS (firmware: UPS2000A, V2R1C1SPC40, P1.0-D1.0)
 * UPS2000-G-3KRTS (firmware: UPS2000G, V2R1C1SPC50, P1.0-D1.0)
+* UPS2000-G-3KRTL (firmware: UPS2000A, V2R1C1SPC40, P1.0-D1.0)
 
 If your model is not in the list, we encourage you to report successful
 or unsuccessful results to the bug tracker or the mailing list.
diff --git a/docs/man/hwmon_ina219.txt b/docs/man/hwmon_ina219.txt
new file mode 100644
index 0000000000..9cf8394186
--- /dev/null
+++ b/docs/man/hwmon_ina219.txt
@@ -0,0 +1,141 @@
+HWMON_INA219(8)
+===============
+
+NAME
+----
+
+hwmon_ina219 - driver for UPS based on INA219
+
+SYNOPSIS
+--------
+
+*hwmon_ina219* -h
+
+*hwmon_ina219* -a 'UPS_NAME' ['OPTIONS']
+
+NOTE: This man page only documents the specific features of the *hwmon_ina219*
+driver. For information about the core driver, see linkman:nutupsdrv[8].
+
+The driver implements reading of current and voltage from INA219 by using hwmon
+sysfs API of the Linux Kernel. There is no other UPS-like logic in there. Based
+on the measurements of the battery voltage and charging current, the driver
+makes assumptions of the current state of the system.
+
+SUPPORTED HARDWARE
+------------------
+
+The *hwmon_ina219* driver is based on setup with Raspberry PI Compute Module 4
+and its baseboard Waveshare CM4-POE-UPS-BASE.
+
+EXTRA ARGUMENTS
+---------------
+
+The required parameter for this driver:
+
+*port*='hwmon-dir'::
+Path to appropriate /sys/hwmon/hwmonX or 'auto' to detect automatically.
+
+Optional parameters:
+
+*default.battery.charge.low*='low-battery-threshold'::
+Threshold for low battery state (in percent).
+
+*default.battery.voltage.nominal*='voltage-value'::
+Nominal voltage (V) value of utilized batteries, used to derive their low
+and high watermark settings (see below). Default: 3.6.
++
+Known pre-sets include: `3.6`, `3.7`, `3.8`, `3.85`.
+
+*default.battery.voltage.low*='voltage-value'::
+Low voltage (V) value of used batteries. Practically, it denotes depleted
+batteries. If not given, it is derived from the *battery.voltage.nominal*.
+
+*default.battery.voltage.high*='voltage-value'::
+High voltage (V) value of used batteries. Practically, it denotes fully
+charged batteries. If not given, it is derived from the
+*battery.voltage.nominal*.
+
+INSTALLATION
+------------
+
+This driver is specific to the Linux hwmon API.
+
+When using with the Waveshare CM4-POE-UPS-BASE baseboard, there are few steps
+to be done to enable access to the INA219 circuit:
+
+. edit boot/config.txt:
++
+----
+  dtparam=i2c_vc=on
+  dtoverlay=i2c-ina219
+----
+
+. create a new device tree overlay file i2c-ina219.dts:
++
+----
+/dts-v1/;
+/plugin/;
+
+/ {
+    compatible = "brcm,bcm2835";
+
+    fragment@0 {
+        target = <&i2c_csi_dsi>;
+        __overlay__ {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            ina219@43 {
+                status = "okay";
+                compatible = "ti,ina219";
+                reg = <0x43>;
+                shunt-resistor = <100000>;  // R100
+            };
+        };
+    };
+};
+----
+
+. convert i2c-ina219.dts to dtbo and place it into /boot/overlays:
++
+----
+$ dtc -@ -I dts -O dtb -o /boot/overlays/i2c-ina219.dtbo i2c-ina219.dts
+----
+
+. configure hwmon_ina219 UPS driver for NUT (ups.conf):
++
+----
+[ina219]
+driver = hwmon_ina219
+port = auto
+----
+
+KNOWN ISSUES AND BUGS
+---------------------
+
+The driver shutdown function is not implemented.
+
+AUTHORS
+-------
+
+Andrew Anderson <aander07@gmail.com>
+
+SEE ALSO
+--------
+
+The core driver:
+~~~~~~~~~~~~~~~~
+
+linkman:nutupsdrv[8]
+
+Internet resources:
+~~~~~~~~~~~~~~~~~~~
+
+* Initial pull requests adding this driver:
+** https://github.com/networkupstools/nut/pull/2430
+** https://github.com/networkupstools/nut/issues/2378
+
+* Baseboard with INA219: https://www.waveshare.com/wiki/CM4-POE-UPS-BASE
+* TI INA219: https://www.ti.com/lit/ds/symlink/ina219.pdf
+
+* The NUT (Network UPS Tools) home page: https://www.networkupstools.org/
diff --git a/docs/man/nut-scanner.txt b/docs/man/nut-scanner.txt
index df635160f3..075589c152 100644
--- a/docs/man/nut-scanner.txt
+++ b/docs/man/nut-scanner.txt
@@ -78,38 +78,66 @@ an 'end IP'. See specific SNMP OPTIONS for community and security settings.
 
 *-M* | *--xml_scan*::
 Scan XML/HTTP devices. Can broadcast a network message on the current network
-interfaces to retrieve XML/HTTP capable devices. No IP required in this mode.
+interface(s) to retrieve XML/HTTP capable devices. No IP required in this mode.
+If IP address ranges are specified, they would be scanned instead of a broadcast.
 
 *-O* | *--oldnut_scan*::
 Scan NUT devices (i.e. upsd daemon) on IP ranging from 'start IP' to 'end IP'.
 
 *-n* | *--nut_simulation_scan*::
-Scan NUT simulated devices (.dev files in $CONFPATH).
+Scan NUT simulated devices (`.dev` files in `$NUT_CONFPATH`).
 
 *-A* | *--avahi_scan*::
-Scan NUT servers using Avahi request on the current network interfaces.
-No IP required.
+Scan NUT servers using Avahi request on the current network interface(s).
+No IP address options are required or used.
 
 *-I* | *--ipmi_scan*::
 Scan NUT compatible power supplies available via IPMI on the current host,
-or over the network.
+or over the network if IP address ranges are specified.
 
 *-E* | *--eaton_serial* 'serial ports'::
 Scan Eaton devices (XCP and SHUT) available via serial bus on the current host.
 This option must be requested explicitly, even for a complete scan.
 'serial ports' can be expressed in various forms:
-
++
 - 'auto' to scan all serial ports.
 - a single character indicating a port number ('0' (zero) for /dev/ttyS0 and
-/dev/ttyUSB0 on Linux, '1' for COM1 on Windows, 'a' for /dev/ttya on Solaris...)
+  /dev/ttyUSB0 on Linux, '1' for COM1 on Windows, 'a' for /dev/ttya on Solaris...)
 - a range of N characters, hyphen separated, describing the range of
-ports using 'X-Y', where X and Y are characters referring to the port number.
+  ports using 'X-Y', where X and Y are characters referring to the port number.
 - a single port name.
 - a list of ports name, coma separated, like '/dev/ttyS1,/dev/ttyS4'.
 
 NETWORK OPTIONS
 ---------------
 
+NOTE: The networked buses (such as SNMP, NetXML, IPMI and "Old NUT") allow to
+specify several IP (IPv4 or IPv6) address ranges, down to individual single
+IP addresses.  Normally a new range is specified by a set of one `-s` and one
+`-e` options following each other (in any order).  Lone or consecutive `-s` or
+`-e` options present on the command line would translate to single-IP queries.
+Also a `-m` option squashed between two `-s` and `-e` options would be a new
+range, turning those two into single-IP queries.  This feature does not by
+itself recombine "neighboring" addresses into one range, nor even check for
+duplicate or overlapping specifications.
++
+Also note that some buses require IP address(es) to scan, and others have a
+different behavior when exactly no addresses are specified (it is not currently
+possible to mix the two behaviors in one invocation of the `nut-scanner` tool).
++
+A single-address range may be a host name which would be resolved into one IP
+address by the system resolver. A CIDR using a host name and netmask length
+would be resolved into an IP address and subjected to the mask application,
+to query hosts "near" the named one.
++
+Finally note that currently even if multi-threaded support is available, each
+range specification is a separate fan-out of queries constrained by the timeout.
+Requests to scan many single IP addresses will take a while to complete, much
+longer than if they were a single range.  This will be hopefully fixed in later
+releases.
+
+NOTE: Colon-separated IPv6 addresses must be passed in square brackets.
+
 *-t* | *--timeout* 'timeout'::
 Set the network timeout in seconds. Default timeout is 5 seconds.
 
@@ -124,7 +152,20 @@ If this parameter is omitted, only the 'start IP' is scanned. If 'end IP' is
 less than 'start IP', both parameters are internally permuted.
 
 *-m* | *--mask_cidr* 'IP address/mask'::
-Set a range of IP using CIDR notation.
+Set a range of IP addresses by using CIDR notation.
++
+A special form `-m auto` allows `nut-scanner` to detect local IP address(es)
+and scan corresponding subnet(s) on supported platforms, and `-m auto4` or
+`-m auto6` limits the selected addresses to IPv4 and IPv6 respectively. Only
+the first "auto*" request would be honoured, others ignored with a warning.
++
+An `/ADDRLEN` suffix can be added to the option, to filter out discovered
+subnets with too many bits available for the host address part (avoiding
+millions of scans in the extreme cases).  For example, if your IPv4 LAN's
+network range is `10.2.3.0/24`, its address part is `(32-24)=8`. Note that
+while this is applied to IPv6 networks also, their typical `/64` subnets
+are not likely to have a NUT/SNMP/NetXML/... server *that* close nearby
+(in addressing terms), for a tight filter to find them. Default is `8`.
 
 NUT DEVICE OPTION
 -----------------
@@ -220,8 +261,8 @@ MISCELLANEOUS OPTIONS
 Display NUT version.
 
 *-a* | *--available*::
-Display available bus that can be scanned, depending on how the nut-scanner
-binary program has been compiled. (OLDNUT, USB, SNMP, XML, AVAHI, IPMI).
+Display available buses that can be scanned, depending on how the nut-scanner
+binary program has been compiled. (e.g. OLDNUT, USB, SNMP, XML, AVAHI, IPMI).
 
 *-q* | *--quiet*::
 Display only scan result. No information on currently scanned bus is displayed.
@@ -229,6 +270,12 @@ Display only scan result. No information on currently scanned bus is displayed.
 *-D* | *--nut_debug_level*::
 Raise the debugging level.  Use this multiple times to see more details.
 
+NOTE: The level of debugging needed depends both on nut-scanner and the
+problem you're trying to diagnose.  Therefore, first explain the problem you
+have with `nut-scanner` to a developer/maintainer, before sending them debugging
+output.  More often than not, if you just pick a level, the output may be
+either too limited or too verbose to be of any use.
+
 EXAMPLES
 --------
 
diff --git a/docs/man/nut.conf.txt b/docs/man/nut.conf.txt
index 2df3552645..80c8939153 100644
--- a/docs/man/nut.conf.txt
+++ b/docs/man/nut.conf.txt
@@ -20,13 +20,31 @@ Blank lines are ignored. Lines with a hash ('#') character at the
 1st position of the line are ignored, too.  They can be used to add
 comments.
 
-IMPORTANT NOTE
---------------
+IMPORTANT NOTES
+---------------
 
-This file is intended to be sourced by shell scripts.
-You MUST NOT use spaces around the equal sign!
+* This file is intended to be sourced by shell scripts as well as by
+  service management frameworks like systemd on Linux:
+  - There is no guaranteed `export VAR=VAL` syntax
+  - No guaranteed expansion of variables like `VAR1="$VAR2-something"` --
+    only verbatim assignments
+  - You may need to `export VAR` when sourcing it into init-scripts
+    or other scripts, for eventual propagation of certain settings
+    to NUT programs. Not-exported variables can only be consumed by
+    the script which "sourced" the file (and may choose to `export`
+    them independently).
+
+* You MUST NOT use spaces around the equal sign!
+
+* Practical support for this file and its settings currently varies
+  between different OS packages and NUT sample scripts, but should
+  converge over time.
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
 
 Refer to the EXAMPLE section for illustrations.
+----------------
 
 DIRECTIVES
 ----------
@@ -112,6 +130,59 @@ integration scripts or service units would emit messages about their activity
 troubleshooting via logs or console captures.  Set to `true` to avoid that
 trove of information, if you consider it noise.
 
+*NUT_DEBUG_LEVEL*::
+Optional, defaults to `0`. This setting controls the default debugging message
+verbosity passed to NUT daemons. As an environment variable, its priority sits
+between that of 'DEBUG_MIN' setting of a driver and the command-line options.
+
+*NUT_DEBUG_PID*::
+Optionally add current process ID to tags with debug-level identifiers.
+This may be useful when many NUT daemons write to the same console or log
+file, such as in containers/plugins for Home Assistant, storage appliances...
+
+*NUT_DEBUG_SYSLOG*::
+Optional, unset by default.
+Normally NUT can (attempt to) use the syslog or Event Log (WIN32), but the
+environment variable 'NUT_DEBUG_SYSLOG' allows to bypass it, and perhaps keep
+the daemons logging to stderr (useful e.g. in NUT Integration Test suite to
+not pollute the OS logs, or in systemd where stderr and syslog both go into
+the same journal). Recognized values:
++
+[options="header"]
+|===========================================================================
+| Value       | Description
+| `stderr`    | Disabled and background() keeps stderr attached
+| `none`      | Disabled and background() detaches stderr as usual
+| `default`   | Not disabled
+| unset/other | Not disabled
+|===========================================================================
+
+*NUT_IGNORE_CHECKPROCNAME*::
+Optional, defaults to `false`.  Normally NUT can (attempt to) verify that
+the program file name matches the name associated with a running process,
+when using PID files to send signals.
++
+The `NUT_IGNORE_CHECKPROCNAME` boolean toggle allows to quickly skip such
+verification, in case it causes problems (e.g. NUT programs were renamed
+and do not match built-in expectations).
++
+This environment variable can also be optionally set in init-scripts or
+service methods for `upsd`, `upsmon` and NUT drivers/`upsdrvctl`.
+
+*NUT_QUIET_INIT_UPSNOTIFY*::
+Optional flag to prevent daemons which can notify service management frameworks
+(such as systemd) about passing their lifecycle milestones, to not report
+loudly if they could NOT do so (e.g. running on a system without a framework,
+or misconfigured so they could not report and the OS could eventually restart
+the false-positively identified "unresponsive" service.
++
+Currently such reports, done by default, help troubleshoot service start-up
+and highlight that NUT sources (or package build) did not take advantage of
+tighter OS service management framework integration (if one exists, so that
+developers could focus on adding that). Reasons to set this flag could include
+platforms without such a framework and not expecting one, although nagging
+your favourite OS or contributing development to make it better is also a way.
+
 EXAMPLE
 -------
 
diff --git a/docs/man/nut.exe.txt b/docs/man/nut.exe.txt
new file mode 100644
index 0000000000..c176a89d33
--- /dev/null
+++ b/docs/man/nut.exe.txt
@@ -0,0 +1,130 @@
+NUT.EXE(8)
+==========
+
+NAME
+----
+
+nut.exe - NUT for Windows wrapper for all-in-one service
+
+SYNOPSIS
+--------
+
+*nut.exe* {-h | /?}
+
+*nut.exe* ['OPTIONS']
+
+*nut.exe* (as a service implementation)
+
+DESCRIPTION
+-----------
+
+*nut.exe* wraps NUT programs to start and stop as a Windows service.
+
+Depending on 'nut.conf' setting of 'MODE', it would manage the bundle of
+driver(s), 'upsd' data server and 'upsmon' client, as well as attempt an
+UPS shutdown command in case of FSD handling, or for mere 'netclient' systems
+it would run just the 'upsmon' client to monitor remote UPS device(s) and
+initiate the OS shut down on the local Windows system as applicable.
+
+Beside launching or stopping a set of the NUT programs in certain cases,
+this helper program also allows to register (or un-register) itself as a
+Windows service. To actually manage the service from command line you can
+execute the Windows `net` command, e.g.:
+
+----
+net stop "Network UPS Tools"
+net start "Network UPS Tools"
+----
+
+You can also execute `nut start` to automatically register the service
+(if not yet registered) and start it, and `nut stop` to stop the service
+(if registered and running).
+
+Note that for a Windows machine to act as a NUT data server for further
+clients, you may have to add Windows Firewall rules to allow incoming
+connections (by default to port `3493/tcp`), e.g. using PowerShell to
+elevate (alternately right-click a "Command Prompt" shortcut and select
+"Run as administrator"), and execute `netsh` to actually configure the
+needed "Advanced Firewall" rule:
+
+----
+REM Elevate to administrator status then run netsh to add firewall rule.
+REM Recommended to adapt "LocalIP" to expected listeners of this server,
+REM and "RemoteIP" to your single or comma-separated subnet(s) in CIDR
+REM notation, specific client IP address(es), or ranges of address(es)
+REM (dash-separated, as IP1-IP2).
+
+REM The following goes as one long command line:
+
+powershell.exe -Command "Start-Process netsh.exe -ArgumentList
+  \"advfirewall firewall add rule name=NUT-upsd-data-server
+    dir=in action=allow localip=ANY remoteip=ANY
+    program=%ProgramFiles%\NUT\sbin\upsd.exe
+    localport=3493 protocol=tcp\" -Verb RunAs"
+----
+
+Keep in mind that by default NUT `upsd` only listens on `localhost`, so
+you would need to add some `LISTEN` directives in `upsd.conf` as well.
+
+OPTIONS
+-------
+
+*nut.exe* is currently launched with no arguments when it is intended to
+run as the implementation of a registered Windows service; it would error
+out otherwise.
+
+*/?*::
+Display the help text and exit.
+
+*-h*::
+Display the help text and exit.
+
+*-V*::
+Display NUT version and exit.
+
+*-D*::
+Raise the debug level.  Use this multiple times for additional details.
+The non-trivial debug level would be passed down to launched NUT programs.
+Primarily useful for troubleshooting with the non-service mode.
+
+*-I*::
+Install as a Windows service called "Network UPS Tools".
+
+*-U*::
+Uninstall the Windows service.
+
+*-N*::
+Run once in non-service mode (for troubleshooting).
+
+*start*::
+Install as a Windows service called "Network UPS Tools" (if not yet done),
+and try to start this service.
+
+*stop*::
+Try to stop a Windows service called "Network UPS Tools".
+
+DIAGNOSTICS
+-----------
+
+*nut.exe* should not interact with console message buffers (stdout, stderr)
+much, except when explicitly asked to (e.g. displaying help and NUT version,
+running with verbose debug mode) or when exiting after an attempted service
+initialization while not running in a service context.
+
+Most of normal logging from *nut.exe* goes to the Windows Event Log.
+
+Launched NUT programs may emit messages of their own; their fate when no
+console is attached is questionable.
+
+SEE ALSO
+--------
+
+linkman:nut.conf[5], linkman:ups.conf[5], linkman:nutupsdrv[8],
+linkman:upsd[8], linkman:upsd.conf[5], linkman:upsd.users[5],
+linkman:upsmon[8], linkman:upsmon.conf[5]
+
+Internet resources:
+~~~~~~~~~~~~~~~~~~~
+
+The NUT (Network UPS Tools) home page: https://www.networkupstools.org/
+
diff --git a/docs/man/nut_usb_addvars.txt b/docs/man/nut_usb_addvars.txt
index 10479e7697..0ef343fead 100644
--- a/docs/man/nut_usb_addvars.txt
+++ b/docs/man/nut_usb_addvars.txt
@@ -109,3 +109,34 @@ If you must really know *which* one, it will not!
 Force redundant call to `usb_set_altinterface()`, especially if needed
 for devices serving multiple USB roles where the UPS is not represented
 by the interface number `0` (default).
+
+*usb_config_index*::
+*usb_hid_rep_index*::
+*usb_hid_desc_index*::
+*usb_hid_ep_in*::
+*usb_hid_ep_out*::
+
+Force use of specific interface, endpoint, descriptor index etc. numbers,
+rather than defaulting to 0 (rarely other values in certain drivers for
+some devices known to use non-zero numbers). Specified as a hexadecimal
+number.
++
+As a rule of thumb for `usb_hid_desc_index` discovery, you can see larger
+`wDescriptorLength` values (roughly 600+ bytes) in reports of `lsusb` or
+similar tools.
+
+[NOTE]
+======
+Run-time troubleshooting of USB-capable NUT drivers can involve not only
+raising the common NUT debug verbosity (e.g. using the `DEBUG_MIN` setting
+in linkman:ups.conf[5] or protocol commands to change the `driver.debug`
+value), but may also benefit from LibUSB specific debugging.
+
+For the latter, currently you would have to export the environment variable
+`LIBUSB_DEBUG` before starting a NUT driver (may be set and "exported" via
+linkman:nut.conf[5]), to a numeric value such as `4` ("All messages are
+emitted"). For more details, including the currently supported values, see:
+
+* https://libusb.sourceforge.io/api-1.0/
+* https://libusb.sourceforge.io/api-1.0/group__libusb__lib.html
+======
diff --git a/docs/man/nutconf.txt b/docs/man/nutconf.txt
index 2485f94aaa..3866a9716a 100644
--- a/docs/man/nutconf.txt
+++ b/docs/man/nutconf.txt
@@ -107,6 +107,14 @@ Notification types are:
 - 'REPLBATT' (UPS battery needs replacing)
 - 'NOCOMM' (device is unavailable)
 - 'NOPARENT' (upsmon parent process died, shutdown is impossible)
+- 'CAL' (calibration in progress)
+- 'NOTCAL' (calibration finished)
+- 'OFF' (UPS is administratively OFF or asleep, should wake up on command)
+- 'NOTOFF' (UPS is no longer administratively OFF or asleep)
+- 'BYPASS' (on bypass = powered, not protecting)
+- 'NOTBYPASS' (no longer on bypass)
+- 'SUSPEND_STARTING' (OS is entering sleep/suspend/hibernate mode)
+- 'SUSPEND_FINISHED' (OS just finished sleep/suspend/hibernate mode)
 
  ::
 Notification flags:
diff --git a/docs/man/nutscan.txt b/docs/man/nutscan.txt
index bfef09f52b..7f3390d026 100644
--- a/docs/man/nutscan.txt
+++ b/docs/man/nutscan.txt
@@ -68,6 +68,9 @@ linkman:nutscan_display_parsable[3], linkman:nutscan_display_ups_conf[3],
 linkman:nutscan_new_device[3], linkman:nutscan_free_device[3],
 linkman:nutscan_add_device_to_device[3],
 linkman:nutscan_add_option_to_device[3],
+linkman:nutscan_init_ip_ranges[3],
+linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_add_ip_range[3],
 linkman:nutscan_cidr_to_ip[3]
 
 Internet resources:
diff --git a/docs/man/nutscan_add_ip_range.txt b/docs/man/nutscan_add_ip_range.txt
new file mode 100644
index 0000000000..8270c6cc69
--- /dev/null
+++ b/docs/man/nutscan_add_ip_range.txt
@@ -0,0 +1,77 @@
+NUTSCAN_ADD_IP_RANGE(3)
+=======================
+
+NAME
+----
+
+nutscan_add_ip_range - Add an entry with IP address range (starting
+and ending addresses) to a `nutscan_ip_range_list_t` structure.
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ /* One IP address range: */
+ typedef struct nutscan_ip_range_s {
+    char * start_ip;
+    char * end_ip;
+    struct nutscan_ip_range_s * next;
+ } nutscan_ip_range_t;
+
+ /* List of IP address ranges and helper data: */
+ typedef struct nutscan_ip_range_list_s {
+    nutscan_ip_range_t * ip_ranges;		/* Actual linked list of entries, first entry */
+    nutscan_ip_range_t * ip_ranges_last;	/* Pointer to end of list for quicker additions */
+    size_t ip_ranges_count;			/* Counter of added entries */
+ } nutscan_ip_range_list_t;
+
+
+ size_t nutscan_add_ip_range(
+    nutscan_ip_range_list_t *irl,
+    char * start_ip,
+    char * end_ip);
+
+DESCRIPTION
+-----------
+
+The *nutscan_add_ip_range()* function can create and add a `nutscan_ip_range_t`
+entry based on provided inputs to the specified `nutscan_ip_range_list_t`
+structure.  The resulting amount of entries in the structure is returned,
+or 0 in case of non-fatal errors.
+
+This function skips work if:
+
+* the structure pointer is `NULL` (0 is returned);
+* neither `start_ip` nor `end_ip` were provided, i.e. they have `NULL` values
+  (current list length from the structure is returned);
+* failed to allocate the entry (fatal).
+
+If only one of `start_ip` or `end_ip` values was provided (not `NULL`), a
+single-address range is created with both addresses set to the same pointer
+value.
+
+The structure should be initialized before use by `nutscan_init_ip_ranges()`.
+
+The caller must free the contents of the structure after completing its use
+by calling `nutscan_free_ip_ranges()` (after which the structure can be
+re-used for a new list), and explicitly `free()` the structure object itself if
+it was allocated dynamically (e.g. by calling `nutscan_init_ip_ranges(NULL)`).
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+Currently there are no checks for duplicate or overlapping entries, so the
+same IP addresses and whole IP address ranges can be added to the list (and
+would eventually be scanned) many times.
+
+SEE ALSO
+--------
+
+linkman:nutscan_init_ip_ranges[3], linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_stringify_ip_ranges[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_init[3],
+linkman:nutscan_ip_ranges_iter_inc[3]
diff --git a/docs/man/nutscan_free_ip_ranges.txt b/docs/man/nutscan_free_ip_ranges.txt
new file mode 100644
index 0000000000..567e89dcfe
--- /dev/null
+++ b/docs/man/nutscan_free_ip_ranges.txt
@@ -0,0 +1,43 @@
+NUTSCAN_FREE_IP_RANGES(3)
+=========================
+
+NAME
+----
+
+nutscan_free_ip_ranges - Free contents of a `nutscan_ip_range_list_t`
+structure populated (and optionally created) by `nutscan_init_ip_ranges()`
+and, more importantly, filled by a series of `nutscan_add_ip_range()` calls.
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ void nutscan_free_ip_ranges(nutscan_ip_range_list_t *irl);
+
+DESCRIPTION
+-----------
+
+The *nutscan_free_ip_ranges()* function can free a `nutscan_ip_range_list_t`
+structure. Doing so, it frees the whole linked list of `nutscan_ip_range_t`
+entries, and zeroes out helper properties.
+
+The structure itself is not freed (as it can be a statically allocated
+variable on the stack), and can be re-used for a new list if needed.
+
+The caller must free the structure object if it was allocated dynamically
+(e.g. by calling `nutscan_init_ip_ranges(NULL)`).
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+SEE ALSO
+--------
+
+linkman:nutscan_init_ip_ranges[3], linkman:nutscan_add_ip_range[3],
+linkman:nutscan_stringify_ip_ranges[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_init[3],
+linkman:nutscan_ip_ranges_iter_inc[3]
diff --git a/docs/man/nutscan_init_ip_ranges.txt b/docs/man/nutscan_init_ip_ranges.txt
new file mode 100644
index 0000000000..73094aaefc
--- /dev/null
+++ b/docs/man/nutscan_init_ip_ranges.txt
@@ -0,0 +1,44 @@
+NUTSCAN_INIT_IP_RANGES(3)
+=========================
+
+NAME
+----
+
+nutscan_init_ip_ranges - Initialize contents of a `nutscan_ip_range_list_t`
+structure (and optionally create one in the first place).
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ nutscan_ip_range_list_t * nutscan_init_ip_ranges(nutscan_ip_range_list_t *irl);
+
+DESCRIPTION
+-----------
+
+The *nutscan_init_ip_ranges()* function can prepare a `nutscan_ip_range_list_t`
+structure by zeroing out its fields.  If the argument is `NULL`, the structure
+is dynamically allocated.  Either way, a pointer to it is returned.
+
+A structure passed by caller is not assumed to have any valid contents to free,
+as it may have garbage from stack after allocation.
+
+The caller must free the contents of the structure after completing its use
+by calling `nutscan_free_ip_ranges` (after which the structure can be re-used),
+and explicitly `free()` the structure object itself if it was allocated
+dynamically (e.g. by calling `nutscan_init_ip_ranges(NULL)`).
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+SEE ALSO
+--------
+
+linkman:nutscan_free_ip_ranges[3], linkman:nutscan_add_ip_range[3],
+linkman:nutscan_stringify_ip_ranges[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_init[3],
+linkman:nutscan_ip_ranges_iter_inc[3]
diff --git a/docs/man/nutscan_ip_ranges_iter_inc.txt b/docs/man/nutscan_ip_ranges_iter_inc.txt
new file mode 100644
index 0000000000..abbd12aa0c
--- /dev/null
+++ b/docs/man/nutscan_ip_ranges_iter_inc.txt
@@ -0,0 +1,44 @@
+NUTSCAN_IP_RANGES_ITER_INC(3)
+=============================
+
+NAME
+----
+
+nutscan_ip_ranges_iter_inc - Proceed with iteration of an IP address range
+using a `nutscan_ip_range_list_iter_t` structure.
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ char * nutscan_ip_ranges_iter_inc(nutscan_ip_range_list_iter_t *irliter);
+
+DESCRIPTION
+-----------
+
+The *nutscan_ip_ranges_iter_inc()* function can prepare an iterator from
+the specified `nutscan_ip_range_list_t` structure.
+
+This function skips work if:
+
+* the structure pointer is `NULL` (`NULL` is returned);
+* the structure pointer's `ip_range` list is `NULL` (`NULL` is returned),
+* the structure pointer's `ip_range_iter` pointer is `NULL` (`NULL` is
+  returned).
+
+Returns the next IP address from the currently iterated registered IP
+address range, or switches iteration to the next range if no addresses
+remained in the current one.
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+SEE ALSO
+--------
+
+linkman:nutscan_init_ip_ranges[3], linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_init[3]
diff --git a/docs/man/nutscan_ip_ranges_iter_init.txt b/docs/man/nutscan_ip_ranges_iter_init.txt
new file mode 100644
index 0000000000..4c871c8e9b
--- /dev/null
+++ b/docs/man/nutscan_ip_ranges_iter_init.txt
@@ -0,0 +1,48 @@
+NUTSCAN_IP_RANGES_ITER_INIT(3)
+==============================
+
+NAME
+----
+
+nutscan_ip_ranges_iter_init - Begin iteration of an IP address range using
+a `nutscan_ip_range_list_iter_t` structure.
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ char * nutscan_ip_ranges_iter_init(
+    nutscan_ip_range_list_iter_t *irliter,
+    const nutscan_ip_range_list_t *irl);
+
+DESCRIPTION
+-----------
+
+The *nutscan_ip_ranges_iter_init()* function can prepare an iterator from
+the specified `nutscan_ip_range_list_t` structure, saving it into the
+caller-provided `nutscan_ip_range_list_iter_t` helper object.
+
+Different iterators may be created to walk the same `nutscan_ip_range_list_t`
+list from different scans independently, but the list and its contents should
+not be freed while anyone references it.
+
+This function skips work if:
+
+* the structure pointer is `NULL` (`NULL` is returned);
+* the structure pointer's `ip_range` list is `NULL` (`NULL` is returned).
+
+Returns the first IP address from the first registered IP address range.
+Subsequent addresses can be returned by `nutscan_ip_ranges_iter_inc()`.
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+SEE ALSO
+--------
+
+linkman:nutscan_init_ip_ranges[3], linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_inc[3]
diff --git a/docs/man/nutscan_scan_ipmi.txt b/docs/man/nutscan_scan_ipmi.txt
index a1fddcfce8..9d43210f68 100644
--- a/docs/man/nutscan_scan_ipmi.txt
+++ b/docs/man/nutscan_scan_ipmi.txt
@@ -12,22 +12,29 @@ SYNOPSIS
  #include <nut-scan.h>
 
  nutscan_device_t * nutscan_scan_ipmi(
-       const char * startIP,
-       const char * stopIP,
-       nutscan_ipmi_t * sec);
+        const char * startIP,
+        const char * stopIP,
+        nutscan_ipmi_t * sec);
+
+ nutscan_device_t * nutscan_scan_ip_range_ipmi(
+        nutscan_ip_range_list_t * irl,
+        nutscan_ipmi_t * sec);
 
 DESCRIPTION
 -----------
 
-The *nutscan_scan_ipmi()* function tries to detect IPMI manageable devices.
+The *nutscan_scan_ipmi()* and *nutscan_scan_ip_range_ipmi()* functions
+try to detect IPMI manageable devices.
 
-If 'start_ip' is NULL, the function searches for a local PSU.
+If 'start_ip' for the former or 'irl' for the latter are NULL, the
+respective function searches for a local PSU.
 
 Otherwise, it searches for remote hosts that would serve IPMI protocols,
 and would try to authenticate using the data in 'sec' structure.
-It issues a NUT request on every IP ranging from 'startIP' to 'stopIP',
-where 'stopIP' is optional. Those IP arguments may be either IPv4 or IPv6
-addresses or host names.
+The former issues an IPMI request on every IP ranging from 'startIP' to
+'stopIP', where 'stopIP' is optional; the latter can walk several IP
+address ranges represented by a `nutscan_ip_range_list_t` structure.
+Those IP arguments may be either IPv4 or IPv6 addresses or host names.
 
 You MUST call linkman:nutscan_init[3] before using this function.
 
@@ -57,5 +64,7 @@ linkman:nutscan_display_ups_conf_with_sanity_check[3],
 linkman:nutscan_display_ups_conf[3],
 linkman:nutscan_display_parsable[3], linkman:nutscan_new_device[3],
 linkman:nutscan_free_device[3], linkman:nutscan_add_option_to_device[3],
-linkman:nutscan_add_device_to_device[3], linkman:nutscan_scan_eaton_serial[3],
+linkman:nutscan_init_ip_ranges[3],
+linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_add_ip_range[3],
 linkman:nutscan_cidr_to_ip[3]
diff --git a/docs/man/nutscan_scan_nut.txt b/docs/man/nutscan_scan_nut.txt
index 08c6520c88..1263a6be23 100644
--- a/docs/man/nutscan_scan_nut.txt
+++ b/docs/man/nutscan_scan_nut.txt
@@ -18,13 +18,21 @@ SYNOPSIS
         const char * port,
         useconds_t usec_timeout);
 
+ nutscan_device_t * nutscan_scan_ip_range_nut(
+        nutscan_ip_range_list_t * irl,
+        const char * port,
+        useconds_t usec_timeout);
+
 DESCRIPTION
 -----------
 
-The *nutscan_scan_nut()* function try to detect available NUT services
-and their associated devices. It issues a NUT request on every IP ranging
-from 'startIP' to 'stopIP'. 'startIP' is mandatory, 'stopIP' is optional.
-Those IP arguments may be either IPv4 or IPv6 addresses or host names.
+The *nutscan_scan_nut()* and *nutscan_scan_ip_range_nut()* functions
+try to detect available NUT services and their associated devices.
+The former issues a NUT request on every IP ranging from 'startIP'
+to 'stopIP' (where 'startIP' is mandatory, 'stopIP' is optional);
+the latter can walk several IP address ranges represented by a
+`nutscan_ip_range_list_t` structure. Those IP arguments may be
+either IPv4 or IPv6 addresses or host names.
 
 You MUST call linkman:nutscan_init[3] before using this function.
 
@@ -54,4 +62,7 @@ linkman:nutscan_display_ups_conf[3],
 linkman:nutscan_display_parsable[3], linkman:nutscan_new_device[3],
 linkman:nutscan_free_device[3], linkman:nutscan_add_option_to_device[3],
 linkman:nutscan_add_device_to_device[3], linkman:nutscan_scan_eaton_serial[3],
+linkman:nutscan_init_ip_ranges[3],
+linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_add_ip_range[3],
 linkman:nutscan_cidr_to_ip[3]
diff --git a/docs/man/nutscan_scan_snmp.txt b/docs/man/nutscan_scan_snmp.txt
index 3ae72ccfd1..f89aebdde1 100644
--- a/docs/man/nutscan_scan_snmp.txt
+++ b/docs/man/nutscan_scan_snmp.txt
@@ -18,12 +18,19 @@ SYNOPSIS
         useconds_t timeout,
         nutscan_snmp_t * sec);
 
+ nutscan_device_t * nutscan_scan_ip_range_snmp(
+        nutscan_ip_range_list_t * irl,
+        useconds_t usec_timeout,
+        nutscan_snmp_t * sec);
+
 DESCRIPTION
 -----------
 
-The *nutscan_scan_snmp()* function try to detect NUT compatible SNMP
-devices. It tries SNMP queries on every IP ranging from 'start_ip' to
-'stop_ip'. Those IP arguments may be either IPv4 or IPv6 addresses or
+The *nutscan_scan_snmp()* and *nutscan_scan_ip_range_snmp()* functions
+try to detect NUT compatible SNMP devices. The former tries SNMP queries
+on every IP ranging from 'start_ip' to 'stop_ip'; the latter can walk
+several IP address ranges represented by a `nutscan_ip_range_list_t`
+structure. Those IP arguments may be either IPv4 or IPv6 addresses or
 host names.
 
 You MUST call linkman:nutscan_init[3] before using this function.
@@ -90,4 +97,7 @@ linkman:nutscan_display_ups_conf[3],
 linkman:nutscan_display_parsable[3], linkman:nutscan_new_device[3],
 linkman:nutscan_free_device[3], linkman:nutscan_add_option_to_device[3],
 linkman:nutscan_add_device_to_device[3], linkman:nutscan_scan_eaton_serial[3],
+linkman:nutscan_init_ip_ranges[3],
+linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_add_ip_range[3],
 linkman:nutscan_cidr_to_ip[3]
diff --git a/docs/man/nutscan_scan_xml_http_range.txt b/docs/man/nutscan_scan_xml_http_range.txt
index 70e0a86b23..1c9b667c81 100644
--- a/docs/man/nutscan_scan_xml_http_range.txt
+++ b/docs/man/nutscan_scan_xml_http_range.txt
@@ -18,16 +18,24 @@ SYNOPSIS
         useconds_t usec_timeout,
         nutscan_xml_t * sec)
 
+ nutscan_device_t * nutscan_scan_ip_range_xml_http(
+        nutscan_ip_range_list_t * irl,
+        useconds_t usec_timeout,
+        nutscan_xml_t * sec)
+
 DESCRIPTION
 -----------
 
-The *nutscan_scan_xml_http_range()* function tries to detect NUT compatible
-XML/HTTP devices.
+The *nutscan_scan_xml_http_range()* and *nutscan_scan_ip_range_xml_http()*
+functions try to detect NUT compatible XML/HTTP devices.
 
-If 'start_ip' is NULL, the function does this by issuing a broadcast message
-on currently configured network interfaces.
+If 'start_ip' for the former or 'irl' for the latter are NULL, the
+respective function does this by issuing a broadcast message on all
+currently configured network interfaces.
 
-Otherwise, it queries every IP ranging from 'start_ip' to 'stop_ip'.
+Otherwise, the former queries every IP ranging from 'start_ip' to 'stop_ip',
+where 'stopIP' is optional; the latter can walk several IP address ranges
+represented by a `nutscan_ip_range_list_t` structure.
 Those IP arguments may be either IPv4 or IPv6 addresses or host names.
 
 It waits up to 'usec_timeout' microseconds for a response from potential
@@ -55,4 +63,8 @@ linkman:nutscan_display_ups_conf_with_sanity_check[3],
 linkman:nutscan_display_ups_conf[3],
 linkman:nutscan_display_parsable[3], linkman:nutscan_new_device[3],
 linkman:nutscan_free_device[3], linkman:nutscan_add_option_to_device[3],
-linkman:nutscan_add_device_to_device[3], linkman:nutscan_scan_eaton_serial[3]
+linkman:nutscan_add_device_to_device[3], linkman:nutscan_scan_eaton_serial[3],
+linkman:nutscan_init_ip_ranges[3],
+linkman:nutscan_free_ip_ranges[3],
+linkman:nutscan_add_ip_range[3],
+linkman:nutscan_cidr_to_ip[3]
diff --git a/docs/man/nutscan_stringify_ip_ranges.txt b/docs/man/nutscan_stringify_ip_ranges.txt
new file mode 100644
index 0000000000..cc14793f10
--- /dev/null
+++ b/docs/man/nutscan_stringify_ip_ranges.txt
@@ -0,0 +1,39 @@
+NUTSCAN_STRINGIFY_IP_RANGES(3)
+==============================
+
+NAME
+----
+
+nutscan_stringify_ip_ranges - Collect contents of a `nutscan_ip_range_list_t`
+structure into a string buffer that can be further printed into logs.
+
+SYNOPSIS
+--------
+
+ #include <nut-scan.h>
+
+ const char * nutscan_stringify_ip_ranges(nutscan_ip_range_list_t *irl);
+
+DESCRIPTION
+-----------
+
+The *nutscan_stringify_ip_ranges()* function can walk a `nutscan_ip_range_list_t`
+structure to report its contents: count of list items, and a comma-separated
+listing with each item as a single token (if `start_ip==end_ip` in that range)
+or a range as `start_ip .. end_ip`.
+
+Returns a pointer to internal statically allocated buffer which would be
+overwritten by subsequent calls, but does not have to be freed by caller.
+
+NOTES
+-----
+
+Technically, the function is currently defined in 'nutscan-ip.h' file.
+
+SEE ALSO
+--------
+
+linkman:nutscan_free_ip_ranges[3], linkman:nutscan_add_ip_range[3],
+linkman:nutscan_cidr_to_ip[3],
+linkman:nutscan_ip_ranges_iter_init[3],
+linkman:nutscan_ip_ranges_iter_inc[3]
diff --git a/docs/man/nutupsdrv.txt b/docs/man/nutupsdrv.txt
index e1cc17722a..6d6fe6564a 100644
--- a/docs/man/nutupsdrv.txt
+++ b/docs/man/nutupsdrv.txt
@@ -114,6 +114,13 @@ are:
 	           which can not be applied "on the fly" (may fail for
 	           critical changes like run-time user/group accounts)
 /////////
+	*exit*;;   tell the currently running driver instance to just exit
+	           (so an external caller like the new driver instance, or
+	           the systemd or SMF frameworks would start another copy)
+
+With recent NUT releases, such commands can be sent using the Unix socket
+for driver-server interaction. As a fallback, like older releases, signals
+can be sent to the old driver instance's PID (where possible).
 
 *-P* 'pid'::
 Send the command signal above using specified PID number, rather than
diff --git a/docs/man/riello_ser.txt b/docs/man/riello_ser.txt
index a9c684f51f..12ebb179ad 100644
--- a/docs/man/riello_ser.txt
+++ b/docs/man/riello_ser.txt
@@ -4,7 +4,7 @@ RIELLO_SER(8)
 NAME
 ----
 
-riello_ser - Driver for Riello UPS Protocol UPS equipment
+riello_ser - Driver for Riello UPS Protocol UPS equipment via serial port connections
 
 SYNOPSIS
 --------
@@ -25,6 +25,34 @@ UPS GPSER and SENTR protocols.
 
 Older Riello UPS products are not supported.
 
+EXTRA ARGUMENTS
+---------------
+
+You may need to tweak some settings, depending on the make and model of your
+UPS (see linkman:ups.conf[5]):
+
+*localcalculation*::
+When enabled, driver will calculate values of `battery.runtime` and
+`battery.charge` "locally" in the driver. This is for some Riello models
+which provide incorrect values in hardware readings, or none at all.
+This "local calculation" is done according to nominal battery capacity,
+nominal battery voltage, actual battery charge, maximum and actual UPS
+load.
++
+You may want to also configure 'default.battery.voltage.low' and
+'default.battery.voltage.high' in case the built-in default range
+(from 10.7V to 12.9V) does not match your hardware, or give a shot
+to 'default.battery.voltage.nominal' (e.g. '24') if your device does
+not serve that either.
++
+NOTE: Lead (PbAc) battery charge graph is not linear, so guesstimated
+charge value may not be perfectly accurate. However it should be good
+enough to determine battery actual status and roughly estimate the time
+it can still power the system.
++
+WARNING: This keyword may be deprecated in future releases of the driver,
+in favor of `runtimecal` and other settings which it requires (as seen in
+linkman:nutdrv_qx[8], linkman:blazer_ser[8] and linkman:blazer_usb[8] drivers).
 
 AUTHOR
 ------
@@ -34,8 +62,13 @@ Massimo Zampieri
 SEE ALSO
 --------
 
+Related drivers
+~~~~~~~~~~~~~~~
+
+linkman:riello_usb[8]
+
 The core driver
-~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~
 
 linkman:nutupsdrv[8]
 
diff --git a/docs/man/riello_usb.txt b/docs/man/riello_usb.txt
index 737aa499f7..088a437a5e 100644
--- a/docs/man/riello_usb.txt
+++ b/docs/man/riello_usb.txt
@@ -29,6 +29,33 @@ EXTRA ARGUMENTS
 
 include::nut_usb_addvars.txt[]
 
+You may need to tweak some settings, depending on the make and model of your
+UPS (see linkman:ups.conf[5]):
+
+*localcalculation*::
+When enabled, driver will calculate values of `battery.runtime` and
+`battery.charge` "locally" in the driver. This is for some Riello models
+(iPlug and iDialog series) which provide incorrect values in hardware
+readings, or none at all.
+This "local calculation" is done according to nominal battery capacity,
+nominal battery voltage, actual battery charge, maximum and actual UPS
+load.
++
+You may want to also configure 'default.battery.voltage.low' and
+'default.battery.voltage.high' in case the built-in default range
+(from 10.7V to 12.9V) does not match your hardware, or give a shot
+to 'default.battery.voltage.nominal' (e.g. '24') if your device does
+not serve that either.
++
+NOTE: Lead (PbAc) battery charge graph is not linear, so guesstimated
+charge value may not be perfectly accurate. However it should be good
+enough to determine battery actual status and roughly estimate the time
+it can still power the system.
++
+WARNING: This keyword may be deprecated in future releases of the driver,
+in favor of `runtimecal` and other settings which it requires (as seen in
+linkman:nutdrv_qx[8], linkman:blazer_ser[8] and linkman:blazer_usb[8] drivers).
+
 AUTHOR
 ------
 
@@ -37,8 +64,13 @@ Massimo Zampieri
 SEE ALSO
 --------
 
+Related drivers
+~~~~~~~~~~~~~~~
+
+linkman:riello_ser[8]
+
 The core driver
-~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~
 
 linkman:nutupsdrv[8]
 
diff --git a/docs/man/ups.conf.txt b/docs/man/ups.conf.txt
index aa98feff1e..28c102ca11 100644
--- a/docs/man/ups.conf.txt
+++ b/docs/man/ups.conf.txt
@@ -48,6 +48,11 @@ Here is another example, when connecting a serial UPS on Windows:
 		port = "\\\\.\\COM10"
 		desc = "UPS on a Windows machine"
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
 
 GLOBAL DIRECTIVES
 -----------------
@@ -272,6 +277,21 @@ certain UPSes from working on Mac OS X. If your UPS requires explicitly setting
 the alternate interface, include this flag, and email the nut-upsdev list with
 details about your UPS and operating system.
 
+*usb_config_index*::
+*usb_hid_rep_index*::
+*usb_hid_desc_index*::
+*usb_hid_ep_in*::
+*usb_hid_ep_out*::
+
+Optional.  Force use of specific interface, endpoint, descriptor index etc.
+numbers, rather than defaulting to 0 (rarely other values in certain drivers
+for some devices known to use non-zero numbers). Specified as a hexadecimal
+number.
++
+As a rule of thumb for `usb_hid_desc_index` discovery, you can see larger
+`wDescriptorLength` values (roughly 600+ bytes) in reports of `lsusb` or
+similar tools.
+
 *default.<variable>*::
 
 Optional.  Set a default value for <variable> which is used in case the UPS
diff --git a/docs/man/upsd.conf.txt b/docs/man/upsd.conf.txt
index 5597f483c5..4e8a9c855c 100644
--- a/docs/man/upsd.conf.txt
+++ b/docs/man/upsd.conf.txt
@@ -14,6 +14,12 @@ miscellaneous configuration values.  This file contains details on
 access controls, so keep it secure.  Ideally, only the upsd process
 should be able to read it.
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
+
 CONFIGURATION DIRECTIVES
 ------------------------
 
diff --git a/docs/man/upsdrvctl.txt b/docs/man/upsdrvctl.txt
index 446ed2d411..d68b459e82 100644
--- a/docs/man/upsdrvctl.txt
+++ b/docs/man/upsdrvctl.txt
@@ -11,7 +11,9 @@ SYNOPSIS
 
 *upsdrvctl* -h
 
-*upsdrvctl* ['OPTIONS'] {start | stop | shutdown} ['ups']
+*upsdrvctl* ['OPTIONS'] {start | stop | shutdown | status} ['ups']
+
+*upsdrvctl* ['OPTIONS'] {list | -l} ['ups']
 
 *upsdrvctl* ['OPTIONS'] -c COMMAND ['ups']
 
@@ -25,8 +27,14 @@ whenever possible.
 When used properly, upsdrvctl lets you maintain identical startup
 scripts across multiple systems with different UPS configurations.
 
-Note: For operating systems with service management frameworks, such as
+NOTE: For operating systems with service management frameworks, such as
 Solaris SMF or Linux systemd, the *upsdrvsvcctl* may be a better choice.
+In fact, service instances prepared by linkman:nut-driver-enumerator[8]
+based on contents of your linkman:ups.conf[5] file and automatically
+maintained by the respective framework can conflict with manual execution
+of drivers, so this tool would emit a warning in NUT builds with that
+capability (can be silenced by exporting a `NUT_QUIET_INIT_NDE_WARNING`
+environment variable with any value).
 
 OPTIONS
 -------
@@ -81,6 +89,9 @@ this mode (not saved by default when staying in foreground).
 Drivers will run in the background, regardless of debugging settings,
 as set by *-D* and passed-through by *-d* options.
 
+*-l*::
+Alias for `list` command.
+
 COMMANDS
 --------
 
@@ -118,6 +129,68 @@ NOTE: refer to linkman:ups.conf[5] for using the *nowait* parameter.
 It can be overridden by `NUT_IGNORE_NOWAIT` environment variable
 (e.g. used to work around certain issues with systemd otherwise).
 
+*list*::
+Without a further argument, report all currently known device configuration
+names to `stdout`, one per line. With an argument, also try to report that
+name, but exit with an error code if that name is not known.
+
+NOTE: The tool would exit with an error if `ups.conf` file is not found,
+readable, or does not define any device sections (whose names are reported
+here and managed in other commands).
+
+NOTE: The tool name and NUT version banner line is also printed to `stdout`
+before any other processing. This can be suppressed by `NUT_QUIET_INIT_BANNER`
+environment variable (exported by caller and empty or "true"):
+
+	:; NUT_QUIET_INIT_BANNER=true upsdrvctl list
+	dummy
+	UPS1
+	UPS2
+
+*status*::
+Similar to `list`, but reports more information -- also the driver name, the
+PID if it is running, and result of a signal probe to check it is responding.
+The `NUT_QUIET_INIT_BANNER` suppression can be helpful for scripted parsing.
+If there is anything to print (at least one device is known), the first line
+of status report would be the heading with column names:
+
+	:; NUT_QUIET_INIT_BANNER=true upsdrvctl status
+	UPSNAME              UPSDRV  RUNNING PF_PID  S_RESPONSIVE    S_PID   S_STATUS
+	dummy             dummy-ups  N/A     -3      NOT_RESPONSIVE  N/A
+	eco650           usbhid-ups  RUNNING 3559207 RESPONSIVE      3559207 "OL"
+	UPS2              dummy-ups  RUNNING 31455   RESPONSIVE      31455   "OL BOOST"
+
+Values are TAB-separated, but UPSNAME and UPSDRV may be padded by spaces
+on the right and on the left respectively. Any complex string values would
+be encased in double-quotes.
+
+Fields reported (`PF_*` = according to PID file, if any; `S_*` = via socket
+protocol):
+
+        *UPSNAME*;;      driver section configuration name
+        *UPSDRV*;;       driver program name per `ups.conf`
+        *RUNNING*;;      `RUNNING` if `PF_PID` or `S_PID` is valid,
+                         `STOPPED` if at least one PID value was parsed but
+                         none was found running with a correct program name;
+                         `N/A` if no PID file/socket reply or failed to parse.
+                         First the PID file is consulted, but it may be absent
+                         either due to command-line parameters of daemons, or
+                         due to platform (WIN32). If no PID value was found and
+                         confirmed this way, we fall back to checking the PID
+                         reported via protocol (if available and different).
+        *PF_PID*;;       PID of driver according to PID file (if any), or some
+                         negative values upon errors (as defined in `common.c`)
+                         including an absent PID file, invalid contents, or
+                         unsupported platform for this mechanism (e.g. WIN32)
+        *S_RESPONSIVE*;; `RESPONSIVE` if `PING`/`PONG` during socket protocol
+                         session setup succeeded; `NOT_RESPONSIVE` otherwise
+        *S_PID*;;        PID of driver according to `GETPID` active query,
+                         or `N/A` if the query failed
+        *S_STATUS*;;     Quoted value of `ups.status` variable
+
+This mode does not discover drivers that are not in `ups.conf` (e.g. started
+manually for experiments with many `-x` CLI options).
+
 *-c* 'command'::
 Send 'command' to the background process as a signal.  Valid commands
 are:
@@ -142,6 +215,9 @@ are:
                    which can not be applied "on the fly" (may fail for
                    critical changes like run-time user/group accounts)
 /////////
+        *exit*;;   tell the currently running driver instance to just exit
+                   (so an external caller like the new driver instance, or
+                   the systemd or SMF frameworks would start another copy)
 
 If the `upsdrvctl` was launched to remain in memory and manage NUT driver
 processes, it can receive supported signals and pass them to those drivers.
@@ -174,7 +250,8 @@ background.
 SEE ALSO
 --------
 
-linkman:upsdrvsvcctl[8], linkman:nutupsdrv[8], linkman:upsd[8], linkman:ups.conf[5]
+linkman:upsdrvsvcctl[8], linkman:nut-driver-enumerator[8],
+linkman:nutupsdrv[8], linkman:upsd[8], linkman:ups.conf[5]
 
 Internet resources:
 ~~~~~~~~~~~~~~~~~~~
diff --git a/docs/man/upsdrvsvcctl.txt b/docs/man/upsdrvsvcctl.txt
index e6e00de697..475d005462 100644
--- a/docs/man/upsdrvsvcctl.txt
+++ b/docs/man/upsdrvsvcctl.txt
@@ -11,7 +11,7 @@ SYNOPSIS
 
 *upsdrvsvcctl* -h
 
-*upsdrvsvcctl* ['OPTIONS'] {start | stop } ['ups']
+*upsdrvsvcctl* ['OPTIONS'] {start | stop | status} ['ups']
 
 DESCRIPTION
 -----------
@@ -61,7 +61,13 @@ OPTIONS
 -------
 
 *-h*::
-Display the help text.
+Display the help text, including the built-in version of the script.
+
+*-V*::
+Display the version of NUT binaries (calling *upsdrvctl -V*), which
+normally should not differ much from the built-in version of the script
+shown in help. But with custom builds everything is possible, so it may
+be useful to know.
 
 *-t*::
 Enable testing mode. Testing mode makes upsdrvsvcctl display the actions
@@ -127,6 +133,14 @@ by using the 'maxretry' and 'retrydelay' options - see linkman:ups.conf[5].
 *stop*::
 Stop the UPS driver(s).
 
+*status*::
+Query run-time status of all configured devices (or one specified device).
+Currently defers work to linkman:upsdrvctl[8], to list known device
+configurations and their driver daemon details (PID, responsiveness,
+`ups.status`) and to linkman:nut-driver-enumerator[8] to map device
+names to service unit instances to report their names and states in
+the service management framework.
+
 *upsdrvsvcctl* also supports further operations for troubleshooting the
 mapping of NUT driver section names to the service instance names (which
 may differ due to limitations of various systems).
diff --git a/docs/man/upsmon.conf.txt b/docs/man/upsmon.conf.txt
index a50edb86f7..d7e8b0a4fa 100644
--- a/docs/man/upsmon.conf.txt
+++ b/docs/man/upsmon.conf.txt
@@ -14,9 +14,20 @@ will monitor and to tell it how to shut down the system when necessary.
 It will contain passwords, so keep it secure.  Ideally, only the upsmon
 process should be able to read it.
 
+A minimal configuration should include at least one `MONITOR` instruction,
+`MINSUPPLIES` (may be 0 if this system is only monitoring other NUT servers),
+and a `POWERDOWNFLAG` if this machine is a "primary" system connected to
+the UPS and drives its late-shutdown power-off command in an emergency.
+
 Additionally, other optional configuration values can be set in this
 file.
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
+
 CONFIGURATION DIRECTIVES
 ------------------------
 
@@ -264,6 +275,11 @@ BYPASS;; UPS on bypass (powered, not protecting)
 
 NOTBYPASS;; UPS no longer on bypass
 
+SUSPEND_STARTING;; OS is entering sleep/suspend/hibernate mode
+
+SUSPEND_FINISHED;; OS just finished sleep/suspend/hibernate mode,
+de-activating obsolete UPS readings to avoid an unfortunate shutdown
+
 *NOTIFYFLAG* 'type' 'flag'[+'flag']...::
 
 By default, upsmon sends walls global messages to all logged in users)
@@ -319,14 +335,27 @@ also apply here.
 *POWERDOWNFLAG* 'filename'::
 
 upsmon creates this file when running in primary mode when the UPS needs
-to be powered off.  You should check for this file in your shutdown
-scripts and call `upsdrvctl shutdown` if it exists.
+to be powered off.  You should check for this file in your late shutdown
+scripts and call `upsdrvctl shutdown` if it exists; note that `upsmon -K`
+may be called for this effect, if NUT configuration files remain readable
+at that point (file systems mostly unmounted or changed to read-only).
++
+Historically it was often `/etc/killpower` but nowadays you may want it
+in a temporary filesystem (e.g. under `/run` or `/run/nut` location).
++
+Note that double backslashes must be used for Windows paths, e.g.
+`C:\\Temp\\killpower` (modern Windows may also accept forward slashes
+like `C:/Temp/killpower` but YMMV).
 +
 This is done to forcibly reset the secondary systems, so they don't get
 stuck at the "halted" stage even if the power returns during the shutdown
 process.  This usually does not work well on contact-closure UPSes that
 use the genericups driver.
 +
+WARNING: The `upsmon` binary program does not have a built-in default,
+so this setting MUST be specified in the configuration, in order for the
+late shutdown integration to work on the particular primary-mode system!
++
 See the config-notes.txt file in the docs subdirectory for more information.
 Refer to the section:
 [[UPS_shutdown]] "Configuring automatic shutdowns for low battery events",
@@ -353,6 +382,26 @@ NOTE: so far we support the device reporting an "OFF" state which usually
 means completely un-powering the load; a bug-tracker issue was logged to
 design similar support for just some manageable outlets or outlet groups.
 
+*OBLBDURATION* 'seconds'::
+
+NUT normally raises alarms for immediate shutdown (FSD) for consumers of an
+UPS known to be on battery ("OB") and achieving the low battery status ("LB"),
+if that is their last remaining power source to satisfy their `MINSUPPLIES`
+setting. In some special cases, users may want to delay raising the alarm
+(using the `OBLBDURATION` option) at their discretion and risk of an ungraceful
+shutdown.
++
+A positive value puts "OB LB" state into effect only if it persists for this
+many seconds. A non-positive value makes the FSD effect of detected "OB LB"
+state immediate. Built-in default value is 0 (seconds).
++
+NOTE: If both `OBLBDURATION` and `HOSTSYNC` options are set on the same
+(secondary) `upsmon` client system, and `HOSTSYNC` is shorter, it would be
+effectively ignored: `upsmon` would wait for up to `OBLBDURATION` seconds
+for the "OB LB" state to clear, and then the secondary client logic would
+fall through to immediate shutdown. If the primary system issues an FSD on
+this UPS, that would take an even higher-priority effect as soon as seen.
+
 *RBWARNTIME* 'seconds'::
 
 When a UPS says that it needs to have its battery replaced, upsmon will
diff --git a/docs/man/upsmon.txt b/docs/man/upsmon.txt
index afe4ad6692..ce18f6228e 100644
--- a/docs/man/upsmon.txt
+++ b/docs/man/upsmon.txt
@@ -178,6 +178,13 @@ UPS on bypass (powered, not protecting).
 *NOTBYPASS*::
 UPS no longer on bypass.
 
+*SUSPEND_STARTING*::
+OS is entering sleep/suspend/hibernate mode.
+
+*SUSPEND_FINISHED*::
+OS just finished sleep/suspend/hibernate mode, de-activating
+obsolete UPS readings to avoid an unfortunate shutdown.
+
 
 NOTIFY COMMAND
 --------------
diff --git a/docs/man/upssched.conf.txt b/docs/man/upssched.conf.txt
index f6ea00e457..d6566c6b32 100644
--- a/docs/man/upssched.conf.txt
+++ b/docs/man/upssched.conf.txt
@@ -12,6 +12,12 @@ DESCRIPTION
 This file controls the operations of linkman:upssched[8], the timer-based
 helper program for linkman:upsmon[8].
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
+
 CONFIGURATION DIRECTIVES
 ------------------------
 
diff --git a/docs/man/upsset.conf.txt b/docs/man/upsset.conf.txt
index cfb422928d..a9170cde2c 100644
--- a/docs/man/upsset.conf.txt
+++ b/docs/man/upsset.conf.txt
@@ -13,6 +13,12 @@ This file only does one job--it lets you convince linkman:upsset.cgi[8]
 that your system's CGI directory is secure.  The program will not run
 until this file has been properly defined.
 
+IMPORTANT NOTES
+---------------
+
+* Contents of this file should be pure ASCII (character codes
+  not in range would be ignored with a warning message).
+
 SECURITY REQUIREMENTS
 ---------------------
 
diff --git a/docs/man/usbhid-ups.txt b/docs/man/usbhid-ups.txt
index 323fe53deb..12f9703218 100644
--- a/docs/man/usbhid-ups.txt
+++ b/docs/man/usbhid-ups.txt
@@ -160,6 +160,20 @@ not forcing it to be fully charged all the time.  As long as the current value
 of `battery.charge` remains at or above this threshold percentage (default 100),
 the `OL+DISCHRG` message logging is not triggered by variations of the charge.
 
+*lbrb_log_delay_sec*='num'::
+Set to delay status-setting (and log messages) about device entering `LB` or
+`LB+RB` state.
++
+Some APC BXnnnnMI device models or firmware versions (reportedly 2023-2024)
+frequently report low battery, replace battery, and all ok within a couple
+of seconds, sometimes but not always preceded by OL+DISCHRG (presumably
+calibration). This setting lets the driver ignore short-lived states and
+only pay attention if they persist longer than this setting (and the device
+power state is `OL`).
+
+*lbrb_log_delay_without_calibrating*::
+Set to apply `lbrb_log_delay_sec` even if device is not calibrating.
+
 *disable_fix_report_desc*::
 Set to disable fix-ups for broken USB encoding, etc. which we apply by default
 on certain models (vendors/products) which were reported as not following the
@@ -174,6 +188,15 @@ It is also always possible that NUT fix-ups cause issues on some devices,
 whether due to NUT bugs or because the vendor protocol implementation is
 broken in more than one place.
 
+*powercom_sdcmd_byte_order_fallback*::
+Original `PowerCOM HID` subdriver code (until version 0.7) sent UPS `shutdown`
+and `stayoff` commands in a wrong byte order, than what is needed by actual
+devices seen in the field in 2024.  The byte order is fixed to satisfy new
+devices by default since version 0.71.  Just in case there are different
+firmwares out there with opposite behaviors, we provide this toggle to use
+old behavior in a particular deployment.  Maybe it was just a bug and nobody
+needs this fall-back...
+
 *explore*::
 With this option, the driver will connect to any device, including
 ones that are not yet supported. This must always be combined with the
diff --git a/docs/net-protocol.txt b/docs/net-protocol.txt
index 222180f106..577e29abaa 100644
--- a/docs/net-protocol.txt
+++ b/docs/net-protocol.txt
@@ -142,7 +142,7 @@ Response:
 - 'ENUM': an enumerated type, which supports a few specific values
 - 'STRING:n': this is a string of maximum length n
 - 'RANGE': this is an numeric, either integer or float, comprised in the
-range (see LIST RANGE)
+  range (see LIST RANGE)
 - 'NUMBER': this is a simple numeric value, either integer or float
 
 ENUM, STRING and RANGE are usually associated with RW, but not always.
@@ -153,7 +153,8 @@ float.
 Note that float values are expressed using decimal (base 10) english-based
 representation, so using a dot, in non-scientific notation.  So hexadecimal,
 exponents, and comma for thousands separator are forbidden.
-For example: "1200.20" is valid, while "1,200.20" and "1200,20" are invalid.
+For example: "1200.20" is valid, while "1,200.20" and "1200,20" and "1.2e4"
+are invalid.
 
 
 This replaces the old "VARTYPE" command.
diff --git a/docs/new-drivers.txt b/docs/new-drivers.txt
index 8503a38287..b425a32b56 100644
--- a/docs/new-drivers.txt
+++ b/docs/new-drivers.txt
@@ -214,7 +214,11 @@ UPS status flags like on line (OL) and on battery (OB) live in
 ups.status.  Don't manipulate this by hand.  There are functions which
 will do this for you.
 
-	status_init() -- before doing anything else
+	status_init()   -- before doing anything else (clear internal buffers,
+	                   etc.)
+
+	status_get(val) -- optionally check if a status word had been set
+	                   since the most-recent status_init()
 
 	status_set(val) -- add a status word (OB, OL, etc)
 
diff --git a/docs/nut-names.txt b/docs/nut-names.txt
index 2c48c1959b..2149fccdbc 100644
--- a/docs/nut-names.txt
+++ b/docs/nut-names.txt
@@ -273,6 +273,9 @@ input: Incoming line/power information
 | input.current.low.critical  | Low critical threshold (A)        | 2
 | input.current.high.warning  | High warning threshold (A)        | 10
 | input.current.high.critical | High critical threshold (A)       | 12
+| input.feed.color            | Color of the input feed
+                                (opaque string)                   | 3831236
+| input.feed.desc             | Description of the input feed     | Feed A
 | input.frequency             | Input line frequency (Hz)         | 60.00
 | input.frequency.nominal     | Nominal input line
                                 frequency (Hz)                    | 60
@@ -543,16 +546,28 @@ above in the Time and Date format chapter.
 ambient: Conditions from external probe equipment
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-NOTE: multiple sensors can be exposed using the indexed notation.
-'ambient.*', without index or using '0', relates to the embedded sensor.
-For example: 'ambient.temperature' represent the embedded sensor temperature.
-Other sensors (external, communication card, ...) can use indexes
-from '1' to 'n'. For example: 'ambient.1.temperature' for the first external
-sensor temperature.
+NOTE: *n* stands for the sensors index. A special case is "ambient.0" which is
+equivalent to "ambient" (without index), and represents the default sensor of
+the device.  This is not to be confused with the device embedded sensor, which
+is published as 'ups.temperature'.  The most important data is "ambient.count",
+used to iterate over the whole set of outlets.
+For more information, refer to the NUT sensors management notes chapter
+of the user manual.
 
 [options="header"]
 |==================================================================================
 | Name                                | Description                 | Example value
+| ambient.count                       | Total number of sensors     | 2
+| ambient.n.name                      | Ambient sensor name         | sensor 1
+| ambient.n.id                        | Ambient sensor identifier
+                                        (opaque string)             | 80f09325-2838-5637-b62a-cef9cbe2747
+| ambient.n.address                   | Ambient sensor address
+                                        (opaque string)             | 1
+| ambient.n.parent.serial             | Ambient sensor parent serial number
+                                        (opaque string)             | U603E34000
+| ambient.n.mfr                       | Ambient sensor manufacturer | EATON
+| ambient.n.model                     | Ambient sensor model        | EMPDT1H1C2
+| ambient.n.firmware                  | Ambient sensor firmware     | 01.03.0011
 | ambient.n.present                   | Ambient sensor presence     | yes
 | ambient.n.temperature               | Ambient temperature
                                         (degrees C)                 | 25.40
@@ -600,8 +615,16 @@ sensor temperature.
                                         seen (percent)              | 13
 | ambient.n.contacts.x.status         | State of the dry contact
                                         sensor x                    | open
+| ambient.n.contacts.x.config         | Configuration of the dry
+                                        contact sensor x            | normal-open
+| ambient.n.contacts.x.name           | Name of the dry contact
+                                        sensor x                    | smoke-detector1
 |==================================================================================
 
+NOTE:
+- ambient.n.contacts.x.status may either be the raw status ('open' or 'closed'),
+or may relate to ambient.n.contacts.x.config. In this case, the value can be
+'active' or 'inactive'.
 
 outlet: Smart outlet management
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -685,8 +708,9 @@ outlet collection apply to outlet.group, especially for the indexing 'n'
 and "outlet.group.count".
 
 Most of the data published for outlets also apply to outlet.group,
-including: id, name (similar as outlet "desc"), status, current and
-voltage (including status, alarm and thresholds).
+including: id, name (similar as outlet "desc"), color, status, current and
+voltage (including status, alarm and thresholds). Other actions and settings
+also apply ({delay,timer}.{shutdown,start})
 
 Some specific data to outlet groups exists:
 
@@ -700,6 +724,8 @@ Some specific data to outlet groups exists:
 | outlet.group.n.phase           | Electrical phase to which the
                                    physical outlet group (Gang) is
                                    connected to                   | L1
+| outlet.group.n.input           | Input to which an outlet group
+                                   is connected                   | 1
 |=================================================================================
 
 Example:
diff --git a/docs/nut.dict b/docs/nut.dict
index 96b530f9c3..46a395154f 100644
--- a/docs/nut.dict
+++ b/docs/nut.dict
@@ -1,4 +1,4 @@
-personal_ws-1.1 en 3468 utf-8
+personal_ws-1.1 en 3215 utf-8
 AAC
 AAS
 ABI
@@ -8,10 +8,10 @@ ACK
 ACM
 ACPI
 ACPresent
-ACrms
 ADDR
 ADDRCONFIG
 ADDRINFO
+ADDRLEN
 ADELSYSTEM
 ADK
 ADKK
@@ -38,8 +38,6 @@ ATT
 ATTRS
 ATX
 ATs
-AUTOCOMMIT
-AUTOPUSH
 AVL
 AVR
 AVRLCD
@@ -50,17 +48,11 @@ ActivePower
 AdMiN
 Affero
 Agrain
-AlarmStatus
-AlarmsHelp
 Albanese
-Alcatel
 Alexey
 AllowOverride
 Alm
-AlmCPol
-AlmEnbl
 Amplon
-Ampère
 Andreas
 Andreassen
 Andrzej
@@ -69,6 +61,7 @@ Antonino
 Apodaca
 AppData
 AppVeyor
+ArgumentList
 Arjen
 Arkadiusz
 Armin
@@ -80,12 +73,8 @@ Asium
 Ates
 AudibleAlarmControl
 AuthConfig
-AutoFrq
-AutoMsg
-AutoRst
 Autobook
 Autoconfigure
-Autostartup
 Avocent
 Axel
 Axxium
@@ -96,7 +85,6 @@ BATTTEMP
 BATTV
 BATTVOLT
 BBBB
-BBHyst
 BCD
 BCHARGE
 BCM
@@ -108,37 +96,30 @@ BP
 BQ
 BRD
 BTEST
-BTIntervl
 BTS
-BTTime
 BTV
 BUFRD
 BUZ
+BXnnnnMI
 BYP
 BZ
 BZOFF
 BZON
 BackPro
 BackUPS
-BadPW
 Bads
 Baggesen
 Bakos
 Balker
 Bartek
-BattTstFail
 BatteryA
 BatteryB
-BaudRt
 Baulé
 BayTech
-BeepTone
 Belkin's
 Benedikt
 Berge
 Berzonis
-BestPort
-BiWeekly
 Bieringer
 BigServers
 BlaXwan
@@ -164,7 +145,6 @@ CA's
 CABAC
 CAs
 CBI
-CBLimit
 CCC
 CCCC
 CDC
@@ -176,6 +156,7 @@ CERTIDENT
 CERTREQUEST
 CERTVERIF
 CEST
+CHECKPROCNAME
 CHOST
 CHRG
 CL
@@ -185,6 +166,7 @@ CLOCAL
 CMDDESC
 CMDSCRIPT
 CN
+COLSPAN
 COMLI
 COMMBAD
 COMMFAULT
@@ -200,10 +182,8 @@ CPPFLAGS
 CPUs
 CRC
 CREAD
-CROSSTALK
 CSN
 CSS
-CSUM
 CTB
 CUDA
 CVE
@@ -215,12 +195,11 @@ Casar
 CentOS
 Centralion
 ChangeLog
-ChargdV
 Chatziathanassiou
 CheckUPS
 CheckUPSAvailable
 Checksum
-Chiou
+Christoph
 Chu
 Cichowski
 CircleCI
@@ -229,14 +208,12 @@ CodingStyle
 Collver
 Colombier
 Comfo
-ConITm
-ConVTm
+CommandLineTools
 ConfigVoltage
 ConnectUPS
 Corbelli
 Corbolante
 Coutadeur
-CrestF
 Ctrl
 Cuvellard
 Cyber
@@ -286,15 +263,15 @@ DTE
 DTrace
 DUMPALL
 DUMPDONE
+DUMPSTATUS
+DUMPVALUE
 DWAKE
 DWITH
 DX
 Daniele
 Dashjr
 DataRoom
-Dbnc
 Ddtrace
-DeepTstFail
 Defensor
 DeltaUPSv
 DesktopFileName
@@ -304,7 +281,6 @@ DeviceLogin
 DeviceLogout
 Dgtk
 Dharm
-DiSplay
 Diehl
 Dietze
 DigitalOcean
@@ -332,6 +308,7 @@ EL
 ELCD
 EMI
 EMP
+EMPDT
 ENDFOR
 ENV
 EOC
@@ -361,13 +338,8 @@ Elio
 Elizarov
 Eltek
 Emilien
-EmmmmDnnnnn
 Energia
 EnergySaving
-EpbrashcDoegfl
-Eqls
-EqlzInvl
-EqlzTm
 Erikson
 Eriksson
 Evgeny
@@ -393,7 +365,6 @@ FREHn
 FRELn
 FRU
 FSP
-FTS
 FTTx
 FTUPS
 FV
@@ -402,7 +373,6 @@ Faber
 Fabio
 Fabrice
 Fairstone
-FaltSens
 Farkas
 Feldman
 Ferrups
@@ -411,13 +381,13 @@ Fideltronik
 Filipozzi
 Fiskars
 FlossMetrics
+Fontana
 Forza
 Fosshost
 Frama
 FreeBSD
 FreeDesktop
 FreeIPMI
-FreqSens
 Frolov
 FullLoad
 Fuß
@@ -425,13 +395,12 @@ GC
 GCCVER
 GES
 GETADDRINFO
+GETPID
 GID
-GKrellM
 GND
 GNUmakefile
 GObject
 GPIO
-GPIOCHIP
 GPL
 GPSER
 GRs
@@ -439,7 +408,6 @@ GTK
 GUESSTIMATION
 GUID
 GUIs
-GWD
 GXE
 GXT
 Gabeler
@@ -449,7 +417,6 @@ Gandi
 Gaspar
 Gathman
 Gembe
-GenTestFail
 Gert
 GetRWVars
 GetUPSCommands
@@ -458,23 +425,17 @@ GetUPSNames
 GetUPSVars
 Ghali
 Giese
-Gilles
 GitHub
 GitHub's
-Gnd
 Gnomovision
 GnuTLS
 Goebl
-Golang
 Gomes
 Goncalves
 Gordeev
 Gough
-Grafana
 Grafenthal
 Gtec
-GuardEnd
-GuardSt
 GuideBook
 Guillen
 HB
@@ -495,13 +456,13 @@ HOSTLINK
 HOSTSYNC
 HOWTO
 HPE
-HPS
 HPUX
 HREF
 HUPCL
 HV
 HVT
 HW
+HWMON
 Hajduch
 Hanno
 Harnhammar
@@ -509,14 +470,10 @@ Havard
 Heavner
 Hessenflow
 HiBox
-HiFreq
-HighBatt
 Hirschler
 Hlavinka
 Holger
-HomeKit
 Homebrew
-Homebridge
 Hoogervorst
 Hough
 Hrusecky
@@ -525,7 +482,6 @@ Hurd
 Håvard
 IANA
 IC
-ID's
 IDE
 IDEN
 IDEs
@@ -546,7 +502,6 @@ INTL
 INV
 INVOLT
 IPAR
-IPBX
 IPC
 IPM
 IPP
@@ -565,12 +520,7 @@ Innova
 Integrators
 IntelCC
 IntelliJ
-InvCDly
-InvCPol
-InvMin
 Invensys
-InverterV
-Invter
 IoT
 Ioannou
 JAWAN
@@ -585,7 +535,6 @@ JW
 Jageson
 Jarosch
 Jasuny
-JavaScript
 Javadoc
 Javascript
 Jenkinsfile
@@ -594,9 +543,9 @@ Jong
 Joon
 Jumpered
 KNutClient
-KNutSetting
 KOLFF
 KRT
+KRTL
 KRTS
 KTTS
 Kain
@@ -607,7 +556,6 @@ Kazutoshi
 Kebo
 Keor
 Kersey
-KeyClic
 Kia
 Kierdelewicz
 Kirill
@@ -622,7 +570,6 @@ Krpec
 Kubernetes
 Kx
 LASTXFER
-LBT
 LCDRM
 LCDRT
 LCDRTXL
@@ -654,9 +601,9 @@ LOADPCT
 LOCKFN
 LOCKNAME
 LOTRANS
+LTS
 LUA
 LVM
-LVT
 LYONN
 Lacerda
 Lallement
@@ -671,20 +618,15 @@ LibLTDL
 LibUSB
 LineA
 LineB
-LineSens
 Lintian
 ListClients
 Lite's
+LocalIP
 LogMax
 LogMin
 LowBatt
-LowFreq
-LowRntm
-LowRuntime
 Loyer
-Ltr
 Luca
-Lucent
 Lygre
 Lynge
 MANPATH
@@ -693,11 +635,11 @@ MAXCONN
 MAXLINEV
 MAXPARMAKES
 MBATTCHG
-MCOL
 MCU
 MDigest
 MEC
 MEGATAEC
+MERCHANTABILITY
 MH
 MIBs
 MIMode
@@ -707,13 +649,11 @@ MINTIMEL
 MKDIRPROG
 MLH
 MMM
-MMMMMMMMMMMMMMM
 MNU
 MONITORed
 MOXA
 MPSU
 MQ
-MQTT
 MSI
 MSII
 MSIII
@@ -733,15 +673,11 @@ Malkiewicz
 Mandriva
 Marcio
 Marek
-MariaDB
 Martinezgarza
 Martín
 Marzouk
 Massimo
 Matthijs
-MaxACVI
-MaxACVO
-MaxDCV
 MaxLinear
 McKinnon
 Megaline
@@ -756,9 +692,6 @@ Micropower
 Microsol
 Mikiewicz
 Milkov
-MinACVI
-MinACVO
-MinDCV
 MinGW
 MiniCOL
 MiniGuard
@@ -767,8 +700,6 @@ Moar
 Modbus
 ModemManager
 Modris
-MonAMI
-MonUPS
 Monett
 Morioka
 Morozov
@@ -778,10 +709,8 @@ Mozilla
 Msg
 MultiLink
 Multiplug
-Munin
 MyCompany
 MyPasSw
-MySQL
 MyState
 NAK
 NAS
@@ -795,16 +724,10 @@ NHS
 NMC
 NMCs
 NMS
-NNNNN
-NNNNNNN
-NNNNNNNN
-NNNNNNNNNN
-NNNNNNNNNNNNNNNNNNN
 NOAUTH
 NOBROADCAST
 NOCOMM
 NOCOMMWARNTIME
-NOCONF
 NOGET
 NOMBATTV
 NOMINV
@@ -826,8 +749,6 @@ NTP
 NUT's
 NUTCONF
 NUTClient
-NUTSRC
-NUTServer
 NVA
 NX
 Nadav
@@ -841,6 +762,7 @@ NetInvent
 NetPro
 NetServer
 NetUps
+NetXML
 Netman
 NetworkUPSTools
 Neus
@@ -848,21 +770,16 @@ Niels
 Niklas
 Niro
 Nobreaks
-NodeJS
 Nom
-NomDCV
-NomVIn
-NomVOut
 NotePad
 Novell
-NrLoBatt
 NuGet
 NutException
 Nxx
 OAH
+OBLBDURATION
 OBSOLETION
 OC
-ODH
 OEM
 OEM'ed
 OFFDURATION
@@ -875,8 +792,6 @@ ONF
 ONV
 OOM
 OSABI
-OSC
-OSF
 OSs
 OUTDIR
 OUTPUTV
@@ -884,7 +799,6 @@ OUTVOLT
 OV
 Oden
 OffTime
-OffTmDays
 Ohloh
 Oldworld
 Olli
@@ -894,7 +808,6 @@ OmniOS
 OmniSmart
 OnLine
 OnTime
-OnTmDays
 OneAC
 OpenBSD
 OpenIndiana
@@ -904,7 +817,6 @@ OpenSolaris
 OpenSource
 OpenUPS
 Opengear
-Opengear's
 Opensource
 Opti
 OptiUPS
@@ -913,7 +825,6 @@ Orvaldi
 Orzechowski
 OutletSystem
 OutputOverload
-OvrLds
 PBT
 PBTn
 PBTnn
@@ -927,18 +838,15 @@ PEX
 PFCLCD
 PGFn
 PGP
-PGRn
 PHP
 PHVn
 PINGs
-PINN
 PIPEFN
 PLD
 PLL
 PLVn
 POLLFAIL
 POLLFREQALERT
-POMode
 POSIX
 POWERDOWNFLAG
 POWEREX
@@ -949,7 +857,6 @@ PPD
 PPDn
 PPDnnn
 PPP
-PPPPPPPPPP
 PR
 PR'ed
 PROGRA
@@ -958,17 +865,17 @@ PROTVER
 PRs
 PSA
 PSD
+PSF
 PSFn
 PSGPSER
-PSKxn
 PSSENTR
 PSUs
 PSW
 PSX
+PSZ
 PThreads
 PULS
 PV
-PWLv
 PWR
 PXG
 PYTHONPATH
@@ -985,7 +892,6 @@ Petri
 Petter
 Pezzini
 Phasak
-PhaseWin
 PhoenixContact
 PhoenixTec
 Phoenixtec
@@ -1000,11 +906,9 @@ Potrans
 Poush
 PowerAlert
 PowerCOM
-PowerChute
 PowerCom
 PowerES
 PowerKinetics
-PowerMIB
 PowerMac
 PowerMan
 PowerManagerII
@@ -1016,12 +920,12 @@ PowerPS
 PowerPal
 PowerPanel
 PowerShare
+PowerShell
 PowerShield
 PowerSure
 PowerTech
 PowerTrust
 PowerVS
-PowerVault
 PowerWalker
 PowerWare
 Powerchute
@@ -1032,15 +936,13 @@ Prachi
 Prereqs
 PresentStatus
 Priv
-Procomm
 ProductID
 Progra
+ProgramFiles
 Proxmox
 Prynych
 Pulizzi
-PwrOut
 PyDOC
-PyGTK
 PyNUT
 PyNUTClient
 PyNUTError
@@ -1068,25 +970,24 @@ QPD
 QQ
 QQQ
 QRI
-QSKTn
-QSKn
 QVFW
 QWS
 QinHeng
 Quette
-RAIDiator
 RBWARNTIME
 RDLCK
 RDNT
 RDWR
 README
+REALPATH
 REDi
 REFREPO
+REPLACEBATT
 REPLBATT
 REQSSL
-RESPIN
 RETPCT
 REXX
+RISC
 RK
 RMCARD
 RMCPplus
@@ -1108,15 +1009,13 @@ RWD
 Rackmount
 Radek
 RatedVA
-RatedWatts
-ReadyNAS
 RealSmart
 RedHat
 Redhat
-RefNom
 Regados
 Reinholdtsen
 Remi
+RemoteIP
 Remoting
 Rene
 René
@@ -1128,17 +1027,15 @@ Rickard
 Ridgway
 Riihikallio
 Rik
-RntmK
 Rocketfish
 Rodrigues
 Rodríguez
 Rouben
 Rozman
 Rucelf
+RunAs
 RunUPSCommand
-RuntimeWarning
 RxD
-RxHs
 Ryabov
 SAI
 SASU
@@ -1149,7 +1046,6 @@ SDA
 SDE
 SDFLAG
 SDR
-SDRnnnnn
 SDT
 SELFTEST
 SELinux
@@ -1161,7 +1057,6 @@ SETFL
 SETINFOs
 SETLK
 SFE
-SFTWTMS
 SG
 SGI
 SHA
@@ -1178,8 +1073,6 @@ SIGTERM
 SIGURG
 SIGUSR
 SIGWINCH
-SKOFFn
-SKONn
 SKP
 SKU
 SL
@@ -1197,7 +1090,6 @@ SOCKADDR
 SOCKLEN
 SOFF
 SOLA
-SOLA's
 SOMECO
 SOURCEMODE
 SOV
@@ -1216,6 +1108,7 @@ STI
 STIME
 STO
 STP
+STRARG
 SUNWlibusbugen
 SUNWugen
 SUNWusb
@@ -1250,16 +1143,11 @@ SetRWVar
 Shara
 ShareAlike
 Shaul
-ShdnDbnc
-ShdnDly
-ShdnPol
 ShutDown
-Shutdn
 Sibbald
 Sicon
 Sidorov
 SigLevel
-Signetic
 Silvino
 Sinline
 Sistem
@@ -1267,7 +1155,6 @@ Sistemas
 SlackPack
 Slackware
 SmartBoost
-SmartCell
 SmartNUT
 SmartOnline
 SmartPro
@@ -1294,6 +1181,7 @@ Stanislav
 StatePath
 Stefano
 Stimits
+StrangeOS
 SuSE
 Suatoni
 Sublicensing
@@ -1304,8 +1192,7 @@ Sy
 Sycon
 Symmetra
 Symmetras
-Synology
-SysHrs
+SyntaxWarning
 Sysgration
 SyslogIdentifier
 SystemIO
@@ -1319,6 +1206,7 @@ TCIOFLUSH
 TCSANOW
 TEMPC
 TEMPF
+TESTPASS
 TGS
 TIMELEFT
 TIOCM
@@ -1337,19 +1225,13 @@ TTT
 TXF
 TXG
 TXV
-TXVxx
-TapSwDly
-TapSwPh
 Tchakhmakhtchian
 TcpClient
 Technic
 Technorama
 Tecnoware
 Tefft
-TeleCom
 Telecom
-Televideo
-TeraStation
 Teurlings
 Thanos
 Thecus
@@ -1357,12 +1239,10 @@ Theodor
 Thierry
 Tigra
 Tnn
-ToddGreenfield
 Tomek
 Toolset
 TopGuard
 Toth
-Traceback
 TrackingID
 TrackingResult
 Tripp
@@ -1370,7 +1250,6 @@ TrippLite
 Tru
 Tx
 TxD
-TxHS
 UB
 UBD
 UBR
@@ -1392,6 +1271,7 @@ UPS's
 UPSCONN
 UPSDESC
 UPSHOST
+UPSIC
 UPSIMAGEPATH
 UPSLC
 UPSNOTIFY
@@ -1406,7 +1286,6 @@ UPScode
 UPSes
 UPSilon
 UPSmart
-UPSmon
 UPSonic
 UPSs
 UPStation
@@ -1416,7 +1295,6 @@ USBDEVFS
 USBDevice
 USERADDed
 USV
-USVs
 UTC
 UTalk
 UUU
@@ -1433,7 +1311,6 @@ V'ger
 VALIGN
 VARDESC
 VARTYPE
-VAout
 VER
 VERFW
 VFI
@@ -1458,6 +1335,7 @@ Viewpower
 Viewsonic
 Viktor
 VirCIO
+Visench
 Vout
 Vultech
 Václav
@@ -1478,6 +1356,7 @@ WTU
 Waldie
 WantedBy
 WatchdogSec
+Waveshare
 WebFreak
 Werror
 Weverything
@@ -1490,11 +1369,11 @@ WinNUT
 WinPower
 Wireshark
 Wl
-WordFmt
 Wrede
 XAU
 XC
 XCP
+XCode
 XLA
 XOFF
 XON
@@ -1509,17 +1388,13 @@ XXXX
 XXXXXXXXXXXX
 XYZ
 Xfer
-XferDly
-XfmrRes
 Xlinker
 Xpert
 Xups
-Xymon
 YQ
 YV
 YY
 YYYY
-YYYYMMDD
 YZ
 Ygor
 Yifeng
@@ -1528,7 +1403,6 @@ Yukai
 Yunto
 ZFS
 ZProject
-ZZZZZZZZ
 Zaika
 Zampieri
 Zawadzki
@@ -1537,17 +1411,10 @@ abandonware
 abcd
 ablerex
 abuild
-acVoltsIn
-acVoltsout
-acampsiOut
-acampsiout
 accessmode
 acl
 acm
 acpi
-acquisited
-acvoltsin
-acvoltsout
 acx
 adb
 addcmd
@@ -1563,20 +1430,16 @@ adm
 admin's
 adminbox
 adoc
+advfirewall
 advorder
 ae
 aec
 af
 aggregator
 ai
+aix
 al
 ala
-alarmcenables
-alarmconpolarity
-alarmlog
-alarmshelp
-alarmstatus
-alarmtest
 alertset
 alioth
 alist
@@ -1590,7 +1453,6 @@ altroots
 amd
 anded
 antivirus
-aod
 aon
 ap
 apc
@@ -1637,21 +1499,17 @@ authPassword
 authPriv
 authProtocol
 authType
-autoadjust
 autoboot
 autoconf
 autodetect
 autodetected
 autodetection
-autofrequency
 autogen
 automagically
 automake
-automessage
 autopoint
 autoreconf
 autorestart
-autosaving
 autoscan
 autostart
 autotools
@@ -1673,7 +1531,6 @@ backport
 backported
 backports
 backupspro
-badpassword
 bart
 baseurl
 bashrc
@@ -1685,18 +1542,15 @@ battext
 battlow
 battnumb
 battpacks
-batttestinterval
-batttesttime
 battvoltmult
 battvolts
 baudrate
 baytech
 baz
-bbh
 bcdDevice
+bcm
 bcmxcp
 bd
-beepertone
 belkin
 belkinunv
 bestfcom
@@ -1718,24 +1572,21 @@ bitmapped
 bitmask
 bitness
 bitnesses
-bitwise
 bn
+bool
 boolean
-boostvoolts
 bootable
 bp
 br
 brazil
+brcm
 brotli
 bsd
-bsv
 bt
 bti
 btn
 btnG
 btt
-buckboosthyst
-buckvolts
 buf
 buflen
 bugfix
@@ -1747,20 +1598,19 @@ bullseye
 busport
 busybox
 bv
-bypassvolts
-byv
 cStandard
 cablepower
 calloc
 cb
+cbe
 cbi
 cbl
-cblimit
 ccache
 cd
 cdc
 cdf
 cee
+cef
 centos
 cerr
 certfile
@@ -1769,14 +1619,6 @@ certpasswd
 certpath
 certutil
 certverify
-cfacaod
-cfacaon
-cfacvid
-cfacvin
-cfacvod
-cfacvon
-cfdcvd
-cfdcvn
 cfg
 cfgadm
 cflag
@@ -1786,8 +1628,6 @@ cgi
 cgipath
 cgroup
 cgroupsv
-chargedvbattery
-chargermode
 chargetime
 charset
 checksum
@@ -1798,7 +1638,6 @@ chkconfig
 chmod
 chown
 chr
-christoph
 chroot
 chrooted
 chrooting
@@ -1810,10 +1649,6 @@ ci
 cidr
 cis
 clav
-clearalarms
-clearhistory
-clearlogs
-clearpassword
 clepple
 clicky
 cls
@@ -1830,10 +1665,8 @@ codebase
 codepath
 coldstarts
 collectd
-colspan
 command's
 commandlen
-commentsMap
 committer
 compat
 compilerPath
@@ -1845,14 +1678,8 @@ configurationProvider
 configureaz
 configureaza
 confpath
-consolecontrol
 const
-constantitime
-constantvtime
-constatus
-contdisplay
 contrib
-contstatus
 copyrightable
 coreutils
 cout
@@ -1878,6 +1705,7 @@ crw
 crypto
 csh
 cshdelay
+csi
 css
 cstdint
 ctime
@@ -1886,6 +1714,7 @@ cts
 ctypes
 cua
 cuaa
+curr
 customizations
 cvt
 cwd
@@ -1905,8 +1734,6 @@ datagrams
 dataok
 datasheet
 datastale
-dayofweek
-dbgsym
 dblatex
 dcd
 dcn
@@ -1944,9 +1771,7 @@ devscan
 dfl
 dhcp
 dialout
-difftool
 diffutils
-dipsw
 dir
 disassembly
 discardable
@@ -1964,7 +1789,7 @@ dnf
 dnl
 dnsmasq
 docbook
-dockapp
+docdir
 docs
 dod
 domxml
@@ -1982,13 +1807,20 @@ drvpath
 drwxr
 drwxrwx
 ds
+dsi
 dsr
 dsssl
 dstate
 dt
+dtb
+dtbo
+dtc
 dtds
 dtksh
+dtoverlay
+dtparam
 dtr
+dts
 du
 dumbterm
 dummycons
@@ -2001,7 +1833,6 @@ ePDU
 ePDUs
 eaton
 ec
-echoback
 eco
 edb
 editorconfig
@@ -2028,14 +1859,7 @@ envvar
 envvars
 ep
 epdu
-epodebounce
-epodelay
-epop
-epopolarity
 eq
-equalizeinterval
-equalizetime
-equalizevolts
 errno
 esac
 esupssmart
@@ -2049,10 +1873,10 @@ everyone's
 everything's
 evilhack
 exe
+execfuse
 executables
 executeCommand
 execve
-extendedhistory
 extern
 externalConsole
 extradata
@@ -2060,11 +1884,11 @@ fabula
 facto
 fallthrough
 fatalx
-faultsensitivity
 fc
 fcb
 fcntl
 fd
+fdX
 fds
 fe
 featureReport
@@ -2073,33 +1897,26 @@ fentonups
 fffdddxxx
 ffff
 fi
-fieldset
 fightwarn
-figlineint
-figoffline
-figonline
 filename
 filenames
 filesystem
 filesystems
 firewalling
 firmwares
-flts
 fmt
 fno
 fontconfig
-footnoteref
+fopen
 forceshutdown
 forcessl
 formatconfig
-formatparam
 formatstring
 fosshost
 fp
 freebsd
 freeipmi
 freetype
-freqsensitivity
 frob
 frontends
 fs
@@ -2108,7 +1925,6 @@ fsr
 fstab
 ftdi
 fuji
-fullload
 func
 gamatronic
 gandi
@@ -2148,6 +1964,7 @@ gitk
 gitlab
 gmail
 gmake
+gmtime
 gnuplot
 gnutls
 google
@@ -2162,8 +1979,6 @@ graphviz
 groupadd
 groupname
 gtk
-guardpend
-guardpstart
 guesstimate
 guesstimation
 guez
@@ -2177,6 +1992,7 @@ hasFeature
 hb
 hcd
 hcl
+hexnum
 hg
 hh
 hibernate's
@@ -2185,8 +2001,6 @@ hidparser
 hidraw
 hidtypes
 hidups
-highbattery
-highfrequency
 homebrew
 hoster
 hostname
@@ -2196,6 +2010,7 @@ hotplug
 hotplugging
 hovercharge
 hpe
+hpux
 href
 htaccess
 html
@@ -2206,15 +2021,18 @@ https
 huawei
 hunnox
 hwdb
+hwmon
+hwmonX
 hypervisor
 hypervisors
 iBox
+iDialog
 iDowell
 iManufacturer
+iPlug
 iSerial
 iUSB
 ib
-ibattery
 icd
 iconv
 icp
@@ -2222,13 +2040,10 @@ icu
 idProduct
 idVendor
 ident
-identifymessage
 idleload
-idm
 ie
 ietf
 ifdef
-ifeval
 ifndef
 ignoreFailures
 ignorelb
@@ -2240,6 +2055,7 @@ im
 imagesdir
 img
 imv
+ina
 includePath
 includedir
 inductor
@@ -2260,7 +2076,6 @@ innotech
 inode
 inplace
 installable
-installcheck
 installpkg
 installurl
 instcmd
@@ -2277,12 +2092,7 @@ interprocess
 interruptonly
 interruptsize
 intltool
-invcontdelay
-invcontpolarity
 inverter
-inverterlog
-inverterminutes
-invertervolts
 io
 ioLogik
 ioLogikE
@@ -2300,11 +2110,14 @@ ipp
 ippon
 ipv
 ipxe
+irl
+irliter
 isDefault
 isbmex
 ish
 iso
 isolator
+iter
 ivtscd
 jNUT
 jNut
@@ -2317,17 +2130,13 @@ jimklimov
 journalctl
 jpeg
 jpg
-jpgraph
 jre
 json
-jumboinfo
-jumbotron
 kVA
 kadets
 kaminski
 kde
 keychain
-keyclick
 keygen
 keyout
 keyring
@@ -2344,8 +2153,8 @@ kvm
 labcd
 lan
 langid
-largp
 lasaine
+lbrb
 ld
 ldd
 le
@@ -2356,6 +2165,8 @@ libaugeas
 libavahi
 libc
 libcommon
+libcommonclient
+libcommonstr
 libcppunit
 libcrypto
 libcurl
@@ -2363,6 +2174,7 @@ libdir
 libdummy
 libexec
 libexecdir
+libexpat
 libfreeipmi
 libgd
 libgpgme
@@ -2376,6 +2188,7 @@ libipmimonitoring
 libltdl
 liblzma
 libmodbus
+libname
 libneon
 libnetsnmp
 libnss
@@ -2391,6 +2204,7 @@ libpowerman
 libre
 libregex
 libs
+libserial
 libsnmp
 libssl
 libsystemd
@@ -2412,7 +2226,6 @@ licensors
 liebert
 liebertgxt
 lifecycle
-linesensitivity
 linevoltage
 linkdoc
 linksingledoc
@@ -2420,34 +2233,31 @@ linux
 linuxdoc
 lipo
 listDeviceClients
-listdef
 littleguy
 lk
 lldb
 llvm
 lm
+lmodbus
 ln
 lnetsnmp
 loadPercentage
+localcalculation
 localhost
+localip
+localport
 localtime
 lockf
-lockwashers
 logfacility
 logfile
 login
 logins
 logout
 logrotate
-longterm
 lookup
 loopback
 lowbatt
 lowbattery
-lowfrequency
-lowruntime
-lowvoltsout
-lposix
 lr
 lregex
 lsd
@@ -2463,7 +2273,6 @@ lxc
 lxcbr
 lxccontainer
 lxcfs
-lxml
 lxyz
 lz
 mA
@@ -2483,17 +2292,13 @@ manpage
 manpages
 masterguard
 matcher
-maxacvi
-maxacvo
 maxd
-maxdcv
 maxlength
 maxreport
 maxretry
 maxstartdelay
 maxva
 maxvalue
-maxvi
 maxvo
 mc
 mcedit
@@ -2502,8 +2307,6 @@ mdadm
 mecer
 megatec
 memset
-merchantability
-mergetool
 metadata
 metasys
 methodOfFlowControl
@@ -2519,18 +2322,13 @@ microdowell
 microlink
 microsol
 middleware
-minacvi
-minacvo
 mincharge
-mindcv
 mingw
 minicol
 minruntime
 mins
-minutalk
 minva
 minvalue
-minvi
 minvo
 mips
 mirrorlist
@@ -2539,7 +2337,6 @@ misconfigured
 mkdir
 mmZ
 mmap
-mmddyyyy
 mn
 mockdrv
 modbus
@@ -2548,12 +2345,10 @@ modprobe
 monmaster
 monofasico
 monpasswd
-monslave
 monuser
 morbo
 mortem
 mozilla
-mqtt
 msec
 msg
 msgfmt
@@ -2582,6 +2377,9 @@ mysecurityname
 myups
 myupsname
 nLogic
+nMONITOR
+nPOWERDOWNFLAG
+nSHUTDOWNCMD
 nabcd
 nameserver
 namespace
@@ -2590,15 +2388,15 @@ nanosleep
 nashkaminski
 natively
 nb
+nbproject
 nbr
-nbsp
 nd
-ndcv
 nds
-nearlowbattery
 netcat
 netclient
+netmask
 netserver
+netsh
 netsnmp
 netvision
 networkupstools
@@ -2624,7 +2422,6 @@ nobody's
 nobt
 nodev
 nodownload
-nodtk
 noexec
 noflag
 nogroup
@@ -2632,11 +2429,7 @@ nohang
 noimp
 noinst
 nolock
-nomacvoltsin
-nomacvoltsout
 nombattvolt
-nomdcvolts
-nomfrequency
 noncommercially
 noout
 norating
@@ -2654,7 +2447,6 @@ nowait
 nowarn
 np
 nss
-ntUPSd
 nuget
 num
 numOfBytesFromUPS
@@ -2669,6 +2461,7 @@ nutdevN
 nutdrv
 nutmon
 nutscan
+nutshutdown
 nutsrv
 nutupsdrv
 nutvalue
@@ -2676,12 +2469,8 @@ nvi
 nvo
 nwfilter
 odette
-odt
 offdelay
 offsite
-offt
-offtimedays
-oftd
 oids
 ok
 okhlybov
@@ -2694,15 +2483,11 @@ omnios
 onbatt
 onbattery
 onbattwarn
-onclick
 ondelay
 oneac
 online
 onlinedischarge
 ont
-ontd
-ontimedays
-ontiniedays
 onwards
 ooce
 openSUSE
@@ -2711,7 +2496,6 @@ openipmi
 openjdk
 openlog
 openmp
-opensolaris
 openssh
 openssl
 optimizations
@@ -2719,7 +2503,6 @@ optiups
 oq
 os
 ostream
-otherprotocols
 otheruser
 outliers
 ovmf
@@ -2728,14 +2511,13 @@ pacman
 pacstrap
 parallelized
 param
-paramkeywords
 parsable
 parseconf
+parsers
 passname
 passphrase
 passthrough
 passwd
-passwordlevel
 pathname
 pathnames
 pbzip
@@ -2754,7 +2536,6 @@ pfSense
 pfexec
 pfy
 ph
-phasewindow
 phoenixcontact
 phoenixtec
 picocom
@@ -2772,12 +2553,10 @@ pkgconfig
 pkgin
 plaintext
 plugin
-plugnplay
 pluma
 pmset
 pmu
 png
-pnp
 pollable
 pollfreq
 pollinterval
@@ -2797,12 +2576,9 @@ powermand
 powermust
 powernet
 poweroff
-powerofftime
-poweronmode
-powerontime
-powerouts
 powerpal
 powerpanel
+powershell
 powerup
 powervalue
 powerware
@@ -2831,6 +2607,7 @@ probu
 proc
 productid
 prog
+progname
 prtconf
 ps
 psu
@@ -2840,9 +2617,8 @@ pts
 pty
 pulizzi
 pw
-pwl
+pwd
 pwmib
-pwro
 px
 pxW
 pxg
@@ -2855,9 +2631,6 @@ pynut
 qDEB
 qa
 qemu
-qfs
-qgs
-qpi
 qs
 queequeg
 quiesce
@@ -2865,11 +2638,7 @@ qx
 qx's
 qxflags
 rD
-rackmount
-raquo
 raritan
-ratedva
-ratedwatts
 rb
 rcctl
 readline
@@ -2881,34 +2650,31 @@ rebased
 rebasing
 rebootdelay
 rebranded
-receivexhs
 reconnection
 recv
 redistributors
 reentrancy
 refactored
 refactoring
-referencenominal
 regex
 regtype
 relatime
 releasekeyring
 relicensing
-remoting
+remoteip
 renderer
 renderers
+repindex
 repo
 reportId
 reposurgeon
 repotec
 req
 resetter
-resistive
 resolv
 resync
 ret
 retrydelay
-revdate
 revnumber
 rex
 rexx
@@ -2934,13 +2700,13 @@ rqt
 rsa
 rsync
 rts
+rtu
 ru
 rubygem
 runlevel
 runnable
 runtime
 runtimecal
-runtimek
 runtimes
 rva
 rw
@@ -2957,7 +2723,7 @@ screenshot
 screenshots
 scriptname
 sd
-sdb
+sdcmd
 sddelay
 sdk
 sdl
@@ -2973,9 +2739,13 @@ securityLevel
 securityName
 sed
 selftest
+semver
 sendback
 sendline
 sendmail
+sendsignal
+sendsignalfn
+sendsignalpid
 sequentialized
 ser
 seria
@@ -2988,7 +2758,6 @@ setflags
 setgid
 setinfo
 setpci
-setpoint
 setq
 setuid
 setupCommands
@@ -2998,21 +2767,18 @@ sfr
 sgml
 sgs
 sha
+shellenv
 shm
 shutdownArguments
 shutdowncmd
-shutdowndebounce
 shutdowndelay
-shutdownpolarity
 shutdowntime
-shutup
 si
 siemens
 sig
 sigaction
 sigmask
 signedness
-simplejson
 simu
 sio
 sitesearch
@@ -3020,10 +2786,10 @@ sitop
 sizeof
 ske
 skel
+sl
 slackpkg
 slaveid
 slavesync
-slewrate
 slibtool
 sm
 smartups
@@ -3032,7 +2798,6 @@ sms
 sn
 snailmail
 snmp
-snmpagent
 snmpv
 snmpwalk
 snprintf
@@ -3042,8 +2807,11 @@ socat
 sockdebug
 socketname
 socomec
+solari
 solaris
+solcmn
 solibs
+solint
 solis
 somename
 somepass
@@ -3069,7 +2837,6 @@ stan
 startIP
 startdelay
 startup
-statefilepath
 statepath
 stayoff
 stderr
@@ -3091,7 +2858,9 @@ strcpy
 strdup
 strerror
 strftime
+stringify
 strlen
+strncpy
 strnlen
 strptime
 struct
@@ -3113,10 +2882,12 @@ sublicense
 sublicenses
 submodule
 submodules
+subnet
+subnets
 subtree
 sudo
 suid
-superset
+suppressions
 suseconds
 sv
 svc
@@ -3137,6 +2908,7 @@ sysV
 syscalls
 sysconfdir
 sysconfig
+sysfs
 syslog
 syslogd
 systemctl
@@ -3144,17 +2916,11 @@ systemd
 systemdshutdowndir
 systemdsystemunitdir
 systemdtmpfilesdir
-systemhours
-systemmode
 systemtest
 sysutils
 sysvinit
-tabledef
 tagname
-tapswitchdelay
-tapswitchphase
 targetArchitecture
-tbody
 tcflush
 tcgetattr
 tcl
@@ -3164,10 +2930,9 @@ tcsetattr
 tcsh
 td
 tdriver
-teknologist
+telnetlib
 tempmax
 tempmin
-terminal's
 termios
 testime
 testtime
@@ -3178,11 +2943,9 @@ tgz
 th
 timeframe
 timehead
-timeline
 timername
 timestamp
 timeticks
-tiocm
 tios
 tmp
 tmpfiles
@@ -3194,7 +2957,6 @@ toolset
 topFrame
 topbot
 tport
-transmitxhs
 tripplite
 tripplitesu
 troff
@@ -3253,12 +3015,10 @@ uninstall
 uninterruptible
 uniq
 unistd
-unitidentify
 unix
 unmapped
 unmounts
 unpowered
-unshutup
 unstash
 updateinfo
 upexia
@@ -3279,7 +3039,6 @@ upscode
 upscommon
 upsct
 upsd
-upsd's
 upsdebug
 upsdebugx
 upsdev
@@ -3299,7 +3058,6 @@ upslog
 upslogx
 upsmon
 upsmon's
-upsmonuser
 upsname
 upsonbatt
 upspass
@@ -3323,7 +3081,6 @@ usbhid
 usbif
 usbinfo
 usbmisc
-usbscan
 usbups
 usbus
 usd
@@ -3359,7 +3116,6 @@ varname
 varvalue
 vbatt
 vc
-vectronic
 vendorid
 ver
 verifySourceSig
@@ -3377,20 +3133,14 @@ virtualization
 virtualized
 vivo
 vo
-vod
 voltronic
-von
 vscode
 wDescriptorLength
 waitbeforereconnect
 wakeup
 wc
-wchar
 wdi
-webNUT
-webnut
 webserver
-websitelayout
 wf
 wget
 whitespace
@@ -3403,7 +3153,6 @@ winpthreads
 wix
 wmNUT
 wmnut
-wordformat
 workflow
 workspace
 workspaceFolder
@@ -3425,11 +3174,9 @@ xcalloc
 xcode
 xd
 xe
-xferdelay
 xff
 xfff
 xffff
-xfmrresistance
 xh
 xhci
 xhtml
diff --git a/docs/sock-protocol.txt b/docs/sock-protocol.txt
index bd440cbc18..4442dc2a28 100644
--- a/docs/sock-protocol.txt
+++ b/docs/sock-protocol.txt
@@ -108,10 +108,14 @@ SETFLAGS
 
 Note that this command takes a variable number of arguments, as multiple
 flags are supported.  Also note that they are not crammed together in
-"", since "RW STRING" would mean something completely different.
+"" quotes, since "RW STRING" would mean something completely different.
 
 This also replaces any previous flags for a given variable.
 
+Currently supported flags include `RW`, `STRING` and `NUMBER`
+(detailed in the NUT Network Protocol documentation); unrecognized values
+are quietly ignored.
+
 ADDCMD
 ~~~~~~
 
@@ -126,6 +130,19 @@ DELCMD
 
 	DELCMD load.on
 
+PID
+~~~
+
+	PID <id>
+
+	PID 12345
+
+	PID "StrangeOS process identifier"
+
+Response to `GETPID` query, where we serve platform-specific process
+identifier. On POSIX and many other platforms this would be a numeric
+value, but most generally it should be treated as an opaque string.
+
 DUMPDONE
 ~~~~~~~~
 
@@ -145,6 +162,14 @@ This is sent in response to a PING from the server.  It is only used as
 a sanity check to make sure that the driver has not gotten stuck
 somewhere.
 
+OK
+~~
+
+	OK Goodbye
+
+This is sent in response to a LOGOUT from the server (or more likely from
+a sibling driver or `upsdrvctl` program).
+
 DATAOK
 ~~~~~~
 
@@ -236,6 +261,14 @@ NOTE:
 TRACKING was set to ON on upsd. In this case, driver will later return
 the execution status, using TRACKING.
 
+GETPID
+~~~~~~
+
+The server (or sibling driver instances, or `upsdrvctl` tool) can use
+this to request the platform-specific process identifier of the driver
+process. On POSIX and many other platforms this would be a numeric value,
+but most generally it should be treated as an opaque string.
+
 DUMPALL
 ~~~~~~~
 
@@ -250,6 +283,27 @@ The server can tell when it has a full copy of the data by waiting for
 DUMPDONE.  That special response from the driver is sent once the entire
 set has been transmitted.
 
+DUMPVALUE
+~~~~~~~~~
+
+	DUMPVALUE <varname>
+
+	DUMPVALUE driver.version
+
+Only request the value of specified variable name (and its additional
+metadata in other lines), same as when `DUMPALL` iterates all such names.
+
+The NUT data server or other socket-protocol client should parse the
+response line by line, looking for the SETINFO line to get the value;
+if a DUMPDONE is seen first, the value was not available in the driver.
+
+DUMPSTATUS
+~~~~~~~~~~
+
+	DUMPSTATUS
+
+Effectively an alias to `DUMPVALUE ups.status`.
+
 NOBROADCAST
 ~~~~~~~~~~~
 
@@ -266,6 +320,17 @@ numeric argument. Note that initial default is to receive everything, so
 this command may be useful for connections that disabled broadcasts at
 some point.
 
+LOGOUT
+~~~~~~
+
+Primarily used by communications between driver processes and/or `upsdrvctl`,
+this command allows clients to gracefully close connection to the NUT driver
+which acts as the server on the socket/pipe, avoiding noisy logs about sudden
+disconnection.
+
+	LOGOUT
+	OK Goodbye
+
 Design notes
 ------------
 
diff --git a/drivers/Makefile.am b/drivers/Makefile.am
index 3eede11ff7..53ff78a3c8 100644
--- a/drivers/Makefile.am
+++ b/drivers/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 # Make sure out-of-dir dependencies exist (especially when dev-building parts):
 $(top_builddir)/common/libcommon.la \
@@ -57,7 +57,7 @@ SERIAL_DRIVERLIST = al175 bcmxcp belkin belkinunv bestfcom	\
  gamatronic genericups isbmex liebert liebert-esp2 masterguard metasys	\
  mge-utalk microdowell microsol-apc mge-shut oneac optiups powercom rhino 	\
  safenet nutdrv_siemens-sitop solis tripplite tripplitesu upscode2 victronups powerpanel \
- blazer_ser ivtscd apcsmart apcsmart-old riello_ser sms_ser
+ blazer_ser ivtscd apcsmart apcsmart-old riello_ser sms_ser bicker_ser
 SNMP_DRIVERLIST = snmp-ups
 USB_LIBUSB_DRIVERLIST = usbhid-ups bcmxcp_usb tripplite_usb \
  blazer_usb richcomm_usb riello_usb \
@@ -68,7 +68,7 @@ SERIAL_USB_DRIVERLIST = \
 NEONXML_DRIVERLIST = netxml-ups
 MACOSX_DRIVERLIST = macosx-ups
 MODBUS_DRIVERLIST = phoenixcontact_modbus generic_modbus huawei-ups2000 socomec_jbus adelsystem_cbi apc_modbus invt_modbus
-LINUX_I2C_DRIVERLIST = asem pijuice
+LINUX_I2C_DRIVERLIST = asem pijuice hwmon_ina219
 POWERMAN_DRIVERLIST = powerman-pdu
 IPMI_DRIVERLIST = nut-ipmipsu
 GPIO_DRIVERLIST = generic_gpio_libgpiod
@@ -186,6 +186,8 @@ riello_ser_SOURCES = riello.c riello_ser.c
 riello_ser_LDADD = $(LDADD) -lm
 sms_ser_SOURCES = sms_ser.c
 sms_ser_LDADD = $(LDADD) -lm
+bicker_ser_SOURCES = bicker_ser.c
+bicker_ser_LDADD = $(LDADD) -lm
 
 # non-serial drivers: these use custom LDADD and/or CFLAGS
 
@@ -273,9 +275,23 @@ snmp_ups_CFLAGS = $(AM_CFLAGS)
 snmp_ups_CFLAGS += $(LIBNETSNMP_CFLAGS)
 snmp_ups_LDADD = $(LDADD_DRIVERS) $(LIBNETSNMP_LIBS) -lm
 
+if WITH_SSL
+if !WITH_OPENSSL
+  snmp_ups_CFLAGS += -UNETSNMP_USE_OPENSSL
+endif !WITH_OPENSSL
+  snmp_ups_CFLAGS += $(LIBSSL_CFLAGS)
+  snmp_ups_LDADD += $(LIBSSL_LIBS)
+endif WITH_SSL
+
 # NEON XML/HTTP
 netxml_ups_SOURCES = netxml-ups.c mge-xml.c
 netxml_ups_LDADD = $(LDADD_DRIVERS) $(LIBNEON_LIBS)
+netxml_ups_CFLAGS = $(AM_CFLAGS)
+
+if WITH_SSL
+  netxml_ups_CFLAGS += $(LIBSSL_CFLAGS)
+  netxml_ups_LDADD += $(LIBSSL_LIBS)
+endif
 
 # Powerman
 powerman_pdu_SOURCES = powerman-pdu.c
@@ -334,6 +350,8 @@ asem_LDADD = $(LDADD_DRIVERS) $(LIBI2C_LIBS)
 asem_SOURCES = asem.c
 pijuice_LDADD = $(LDADD_DRIVERS) $(LIBI2C_LIBS)
 pijuice_SOURCES = pijuice.c
+hwmon_ina219_LDADD = $(LDADD_DRIVERS)
+hwmon_ina219_SOURCES = hwmon_ina219.c
 
 # GPIO drivers
 generic_gpio_libgpiod_SOURCES = generic_gpio_common.c generic_gpio_libgpiod.c
@@ -365,7 +383,8 @@ nutdrv_qx_SOURCES += $(NUTDRV_QX_SUBDRIVERS)
 # tracking (which is automatic), but to ensure these files are
 # distributed by "make dist".
 
-dist_noinst_HEADERS = apc-mib.h apc-iem-mib.h apc-hid.h arduino-hid.h baytech-mib.h bcmxcp.h bcmxcp_ser.h	\
+dist_noinst_HEADERS = \
+ apc_modbus.h apc-mib.h apc-iem-mib.h apc-hid.h arduino-hid.h baytech-mib.h bcmxcp.h bcmxcp_ser.h	\
  bcmxcp_io.h belkin.h belkin-hid.h bestpower-mib.h blazer.h cps-hid.h dstate.h	\
  dummy-ups.h explore-hid.h gamatronic.h genericups.h	\
  generic_gpio_common.h generic_gpio_libgpiod.h	\
@@ -394,6 +413,7 @@ dist_noinst_HEADERS = apc-mib.h apc-iem-mib.h apc-hid.h arduino-hid.h baytech-mi
 # for object files. This library is used during the build process,
 # and is not meant to be installed.
 EXTRA_LTLIBRARIES = libdummy.la libdummy_serial.la libdummy_upsdrvquery.la
+
 libdummy_la_SOURCES = main.c dstate.c
 libdummy_la_LDFLAGS = -no-undefined -static
 libdummy_serial_la_SOURCES = serial.c
@@ -409,6 +429,14 @@ libdummy_mockdrv_la_SOURCES = main.c dstate.c
 libdummy_mockdrv_la_CFLAGS = $(AM_CFLAGS) -DDRIVERS_MAIN_WITHOUT_MAIN=1
 libdummy_mockdrv_la_LDFLAGS = -static $(top_builddir)/common/libcommon.la $(top_builddir)/common/libparseconf.la
 
+# Also define a library with serial-port UPS routines needed for nut-scanner
+noinst_LTLIBRARIES = libserial-nutscan.la
+
+libserial_nutscan_la_SOURCES = serial.c bcmxcp_ser.c
+libserial_nutscan_la_LDFLAGS =
+libserial_nutscan_la_LIBADD = $(SERLIBS)
+libserial_nutscan_la_CFLAGS = $(AM_CFLAGS) -I$(top_srcdir)/clients -I$(top_srcdir)/include -I$(top_srcdir)/drivers
+
 dummy:
 
 CLEANFILES = $(EXTRA_LTLIBRARIES) $(EXTRA_PROGRAMS)
diff --git a/drivers/adelsystem_cbi.c b/drivers/adelsystem_cbi.c
index 3f2135b932..6c4d7df174 100644
--- a/drivers/adelsystem_cbi.c
+++ b/drivers/adelsystem_cbi.c
@@ -30,7 +30,7 @@
 #include <timehead.h>
 
 #define DRIVER_NAME "NUT ADELSYSTEM DC-UPS CB/CBI driver"
-#define DRIVER_VERSION "0.02"
+#define DRIVER_VERSION "0.03"
 
 /* variables */
 static modbus_t *mbctx = NULL;							/* modbus memory context */
diff --git a/drivers/al175.c b/drivers/al175.c
index 6ed311a8dc..fe01763492 100644
--- a/drivers/al175.c
+++ b/drivers/al175.c
@@ -52,7 +52,7 @@ typedef	uint8_t byte_t;
 
 
 #define DRIVER_NAME	"Eltek AL175/COMLI driver"
-#define DRIVER_VERSION	"0.14"
+#define DRIVER_VERSION	"0.15"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/apc-mib.c b/drivers/apc-mib.c
index 1c6c575ac6..78924e31c3 100644
--- a/drivers/apc-mib.c
+++ b/drivers/apc-mib.c
@@ -164,9 +164,9 @@ static info_lkp_t apcc_transfer_reasons[] = {
 #define APCC_REBOOT_DO			2
 #define APCC_REBOOT_GRACEFUL	3
 #if 0	/* not used. */
-	#define APCC_OID_SLEEP		".1.3.6.1.4.1.318.1.1.1.6.2.3"
-	#define APCC_SLEEP_ON			"2"
-	#define APCC_SLEEP_GRACEFUL		"3"
+#	define APCC_OID_SLEEP		".1.3.6.1.4.1.318.1.1.1.6.2.3"
+#	define APCC_SLEEP_ON			"2"
+#	define APCC_SLEEP_GRACEFUL		"3"
 #endif
 
 
diff --git a/drivers/apc_modbus.c b/drivers/apc_modbus.c
index 7e437e2fce..4f7cc9fd02 100644
--- a/drivers/apc_modbus.c
+++ b/drivers/apc_modbus.c
@@ -17,13 +17,16 @@
  */
 
 #include "main.h"
+
 #if defined NUT_MODBUS_HAS_USB
-#include "nut_libusb.h"
-#include "libhid.h"
-#include "hidparser.h"
+# include "nut_libusb.h"
+# include "libhid.h"
+# include "hidparser.h"
 #endif /* defined NUT_MODBUS_HAS_USB */
+
 #include "timehead.h"
 #include "nut_stdint.h"
+#include "apc_modbus.h"
 
 #include <ctype.h>
 #include <stdio.h>
@@ -31,7 +34,7 @@
 #include <modbus.h>
 
 #define DRIVER_NAME "NUT APC Modbus driver"
-#define DRIVER_VERSION "0.01"
+#define DRIVER_VERSION "0.10"
 
 #if defined NUT_MODBUS_HAS_USB
 
@@ -89,23 +92,30 @@ upsdrv_info_t upsdrv_info = {
 };
 
 typedef enum {
-	APC_MODBUS_VALUE_TYPE_INT = 0,
-	APC_MODBUS_VALUE_TYPE_UINT,
-	APC_MODBUS_VALUE_TYPE_STRING
+	APC_VT_INT = 0,
+	APC_VT_UINT,
+	APC_VT_STRING
 } apc_modbus_value_types;
 
-static const apc_modbus_value_types apc_modbus_value_types_max = APC_MODBUS_VALUE_TYPE_STRING;
+typedef enum {
+	APC_VF_NONE = 0,
+	APC_VF_RW = (1 << 0)
+} apc_modbus_value_flags;
+
+static const apc_modbus_value_types apc_modbus_value_types_max = APC_VT_STRING;
+
+typedef union {
+	int64_t int_value;
+	uint64_t uint_value;
+	char *string_value;
+} apc_modbus_value_data_t;
 
 typedef struct {
 	apc_modbus_value_types type;
 	const char *format;
 	int scale;
 	void *variable_ptr;
-	union {
-		int64_t int_value;
-		uint64_t uint_value;
-		char *string_value;
-	} data;
+	apc_modbus_value_data_t data;
 } apc_modbus_value_t;
 
 typedef struct {
@@ -178,6 +188,37 @@ static int _apc_modbus_to_string(const uint16_t *value, const size_t value_len,
 	return 1;
 }
 
+static int _apc_modbus_from_string(const char *value, uint16_t *output, size_t output_len)
+{
+	size_t value_len, vi, oi;
+	uint16_t tmp;
+
+	if (value == NULL || output == NULL) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	value_len = strlen(value);
+
+	if (value_len > (output_len * sizeof(uint16_t))) {
+		/* Output buffer too small */
+		return 0;
+	}
+
+	for (vi = 0, oi = 0; vi < value_len && oi < output_len; vi += 2, oi++) {
+		tmp = value[vi] << 8;
+		if (vi + 1 < value_len)
+			tmp |= value[vi + 1];
+		output[oi] = tmp;
+	}
+
+	for (; oi < output_len; oi++) {
+		output[oi] = 0;
+	}
+
+	return 1;
+}
+
 /* Converts a Modbus integer to a uint64_t.
  * See MPAO-98KJ7F_EN section 1.3.1 Numbers. */
 static int _apc_modbus_to_uint64(const uint16_t *value, const size_t value_len, uint64_t *output)
@@ -197,6 +238,51 @@ static int _apc_modbus_to_uint64(const uint16_t *value, const size_t value_len,
 	return 1;
 }
 
+static int _apc_modbus_from_uint64(uint64_t value, uint16_t *output, size_t output_len)
+{
+	ssize_t oi;
+	size_t bits;
+
+	if (output == NULL) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	bits = output_len * sizeof(uint16_t) * 8;
+	if (bits < 64) {
+		if (value > ((1ULL << bits) - 1)) {
+			/* Overflow */
+			return 0;
+		}
+	}
+
+	for (oi = output_len - 1; oi >= 0; oi--) {
+		output[oi] = (uint16_t)(value & 0xFFFF);
+		value >>= 16;
+	}
+
+	return 1;
+}
+
+static int _apc_modbus_from_uint64_string(const char *value, uint16_t *output, size_t output_len)
+{
+	uint64_t value_uint;
+	char *endptr;
+
+	if (value == NULL || output == NULL) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	errno = 0;
+	value_uint = strtoull(value, &endptr, 0);
+	if (endptr == value || *endptr != '\0' || errno > 0) {
+		return 0;
+	}
+
+	return _apc_modbus_from_uint64(value_uint, output, output_len);
+}
+
 static int _apc_modbus_to_int64(const uint16_t *value, const size_t value_len, int64_t *output)
 {
 	size_t shiftval;
@@ -212,6 +298,50 @@ static int _apc_modbus_to_int64(const uint16_t *value, const size_t value_len, i
 	return 1;
 }
 
+static int _apc_modbus_from_int64(int64_t value, uint16_t *output, size_t output_len)
+{
+	ssize_t oi;
+	size_t bits;
+
+	if (output == NULL) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	bits = output_len * sizeof(uint16_t) * 8;
+	if (value > ((1LL << (bits - 1)) - 1) ||
+		value < -(1LL << (bits - 1))) {
+		/* Overflow */
+		return 0;
+	}
+
+	for (oi = output_len - 1; oi >= 0; oi--) {
+		output[oi] = (uint16_t)(value & 0xFFFF);
+		value >>= 16;
+	}
+
+	return 1;
+}
+
+static int _apc_modbus_from_int64_string(const char *value, uint16_t *output, size_t output_len)
+{
+	int64_t value_int;
+	char *endptr;
+
+	if (value == NULL || output == NULL) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	errno = 0;
+	value_int = strtoll(value, &endptr, 0);
+	if (endptr == value || *endptr != '\0' || errno > 0) {
+		return 0;
+	}
+
+	return _apc_modbus_from_int64(value_int, output, output_len);
+}
+
 static int _apc_modbus_to_double(const apc_modbus_value_t *value, double *output)
 {
 	int factor;
@@ -225,14 +355,38 @@ static int _apc_modbus_to_double(const apc_modbus_value_t *value, double *output
 
 	assert(value->type <= apc_modbus_value_types_max);
 	switch (value->type) {
-		case APC_MODBUS_VALUE_TYPE_INT:
+		case APC_VT_INT:
 			*output = (double)value->data.int_value / factor;
 			break;
-		case APC_MODBUS_VALUE_TYPE_UINT:
+		case APC_VT_UINT:
 			*output = (double)value->data.uint_value / factor;
 			break;
-		case APC_MODBUS_VALUE_TYPE_STRING:
+		case APC_VT_STRING:
 			return 0;
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
 	return 1;
@@ -332,7 +486,7 @@ static int _apc_modbus_voltage_to_nut(const apc_modbus_value_t *value, char *out
 		return 0;
 	}
 
-	if (value->type != APC_MODBUS_VALUE_TYPE_UINT) {
+	if (value->type != APC_VT_UINT) {
 		return 0;
 	}
 
@@ -360,7 +514,7 @@ static int _apc_modbus_efficiency_to_nut(const apc_modbus_value_t *value, char *
 		return 0;
 	}
 
-	if (value->type != APC_MODBUS_VALUE_TYPE_INT) {
+	if (value->type != APC_VT_INT) {
 		return 0;
 	}
 
@@ -413,7 +567,7 @@ static int _apc_modbus_status_change_cause_to_nut(const apc_modbus_value_t *valu
 		return 0;
 	}
 
-	if (value->type != APC_MODBUS_VALUE_TYPE_UINT) {
+	if (value->type != APC_VT_UINT) {
 		return 0;
 	}
 
@@ -526,35 +680,150 @@ static int _apc_modbus_status_change_cause_to_nut(const apc_modbus_value_t *valu
 
 static apc_modbus_converter_t _apc_modbus_status_change_cause_conversion = { _apc_modbus_status_change_cause_to_nut, NULL };
 
+static int _apc_modbus_string_join(const char *values[], size_t values_len, const char *separator, char *output, size_t output_len)
+{
+	size_t i;
+	size_t output_idx;
+	int res;
+
+	if (values == NULL || values_len == 0 || separator == NULL || output == NULL || output_len == 0) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	output_idx = 0;
+
+	for (i = 0; i < values_len && output_idx < output_len; i++) {
+		if (values[i] == NULL)
+			continue;
+
+		if (i == 0) {
+			res = snprintf(output + output_idx, output_len - output_idx, "%s", values[i]);
+		} else {
+			res = snprintf(output + output_idx, output_len - output_idx, "%s%s", separator, values[i]);
+		}
+
+		if (res < 0 || (size_t)res >= output_len) {
+			return 0;
+		}
+
+		output_idx += res;
+	}
+
+	return 1;
+}
+
+static int _apc_modbus_battery_test_status_to_nut(const apc_modbus_value_t *value, char *output, size_t output_len)
+{
+	const char *result, *source, *modifier;
+	const char *values[3];
+
+	if (value == NULL || output == NULL || output_len == 0) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	if (value->type != APC_VT_UINT) {
+		return 0;
+	}
+
+	result = NULL;
+	if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_PENDING)) {
+		result = "Pending";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_INPROGRESS)) {
+		result = "InProgress";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_PASSED)) {
+		result = "Passed";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_FAILED)) {
+		result = "Failed";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_REFUSED)) {
+		result = "Refused";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_ABORTED)) {
+		result = "Aborted";
+	}
+
+	source = NULL;
+	if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_PROTOCOL)) {
+		source = "Source: Protocol";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_LOCALUI)) {
+		source = "Source: LocalUI";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_INTERNAL)) {
+		source = "Source: Internal";
+	}
+
+	modifier = NULL;
+	if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_INVALIDSTATE)) {
+		modifier = "Modifier: InvalidState";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_INTERNALFAULT)) {
+		modifier = "Modifier: InternalFault";
+	} else if ((value->data.uint_value & APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_STATEOFCHARGENOTACCEPTABLE)) {
+		modifier = "Modifier: StateOfChargeNotAcceptable";
+	}
+
+	values[0] = result;
+	values[1] = source;
+	values[2] = modifier;
+	return _apc_modbus_string_join(values, SIZEOF_ARRAY(values), ", ", output, output_len);
+}
+
+static apc_modbus_converter_t _apc_modbus_battery_test_status_conversion = { _apc_modbus_battery_test_status_to_nut, NULL };
+
+static const time_t apc_date_start_offset = 946684800; /* 2000-01-01 00:00 */
+
 static int _apc_modbus_date_to_nut(const apc_modbus_value_t *value, char *output, size_t output_len)
 {
-	struct tm *tm_info;
+	struct tm tm_info;
 	time_t time_stamp;
-	const time_t start_offset = 946684800; /* 2000-01-01 00:00 */
 
 	if (value == NULL || output == NULL || output_len == 0) {
 		/* Invalid parameters */
 		return 0;
 	}
 
-	if (value->type != APC_MODBUS_VALUE_TYPE_UINT) {
+	if (value->type != APC_VT_UINT) {
 		return 0;
 	}
 
-	time_stamp = ((int64_t)value->data.uint_value * 86400) + start_offset;
-	tm_info = gmtime(&time_stamp);
-	strftime(output, output_len, "%Y-%m-%d", tm_info);
+	time_stamp = ((int64_t)value->data.uint_value * 86400) + apc_date_start_offset;
+	gmtime_r(&time_stamp, &tm_info);
+	strftime(output, output_len, "%Y-%m-%d", &tm_info);
 
 	return 1;
 }
 
-static apc_modbus_converter_t _apc_modbus_date_conversion = { _apc_modbus_date_to_nut, NULL };
+static int _apc_modbus_date_from_nut(const char *value, uint16_t *output, size_t output_len)
+{
+	struct tm tm_struct;
+	time_t epoch_time;
+	uint64_t uint_value;
+
+	if (value == NULL || output == NULL || output_len == 0) {
+		/* Invalid parameters */
+		return 0;
+	}
+
+	memset(&tm_struct, 0, sizeof(tm_struct));
+	if (strptime(value, "%Y-%m-%d", &tm_struct) == NULL) {
+		return 0;
+	}
+
+	if ((epoch_time = timegm(&tm_struct)) == -1) {
+		return 0;
+	}
+
+	uint_value = (epoch_time - apc_date_start_offset) / 86400;
+
+	return _apc_modbus_from_uint64(uint_value, output, output_len);
+}
+
+static apc_modbus_converter_t _apc_modbus_date_conversion = { _apc_modbus_date_to_nut, _apc_modbus_date_from_nut };
 
 typedef struct {
 	const char *nut_variable_name;
 	size_t modbus_addr;
 	size_t modbus_len; /* Number of uint16_t registers */
 	apc_modbus_value_types value_type;
+	apc_modbus_value_flags value_flags;
 	apc_modbus_converter_t *value_converter;
 	const char *value_format;
 	int value_scale;
@@ -563,50 +832,74 @@ typedef struct {
 
 /* Values that only need to be updated once on startup */
 static apc_modbus_register_t apc_modbus_register_map_inventory[] = {
-	{ "ups.firmware",               516,    8,  APC_MODBUS_VALUE_TYPE_STRING,   NULL,                                           "%s",   0,  NULL    },
-	{ "ups.model",                  532,    16, APC_MODBUS_VALUE_TYPE_STRING,   NULL,                                           "%s",   0,  NULL    }, /* also device.model, filled automatically */
-	{ "ups.serial",                 564,    8,  APC_MODBUS_VALUE_TYPE_STRING,   NULL,                                           "%s",   0,  NULL    }, /* also device.serial, filled automatically */
-	{ "ups.power.nominal",          588,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.0f", 0,  &power_nominal      },
-	{ "ups.realpower.nominal",      589,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.0f", 0,  &realpower_nominal  },
-	{ "ups.mfr.date",               591,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
-	{ "battery.date",               595,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
-	{ "ups.id",                     596,    8,  APC_MODBUS_VALUE_TYPE_STRING,   NULL,                                           "%s",   0,  NULL    },
-	{ NULL, 0, 0, 0, NULL, NULL, 0.0f, NULL }
+	{ "ups.firmware",                   516,    8,  APC_VT_STRING,   0,         NULL,                                           "%s",   0,  NULL    },
+	{ "ups.model",                      532,    16, APC_VT_STRING,   0,         NULL,                                           "%s",   0,  NULL    }, /* also device.model, filled automatically */
+	{ "ups.serial",                     564,    8,  APC_VT_STRING,   0,         NULL,                                           "%s",   0,  NULL    }, /* also device.serial, filled automatically */
+	{ "ups.power.nominal",              588,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.0f", 0,  &power_nominal      },
+	{ "ups.realpower.nominal",          589,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.0f", 0,  &realpower_nominal  },
+	{ "ups.mfr.date",                   591,    1,  APC_VT_UINT,     0,         &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
+	{ "battery.date",                   595,    1,  APC_VT_UINT,     APC_VF_RW, &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
+	{ "ups.id",                         596,    8,  APC_VT_STRING,   APC_VF_RW, NULL,                                           "%s",   0,  NULL    },
+	{ "outlet.group.0.name",            604,    8,  APC_VT_STRING,   APC_VF_RW, NULL,                                           "%s",   0,  NULL    },
+	{ "outlet.group.1.name",            612,    8,  APC_VT_STRING,   APC_VF_RW, NULL,                                           "%s",   0,  NULL    },
+	{ "outlet.group.2.name",            620,    8,  APC_VT_STRING,   APC_VF_RW, NULL,                                           "%s",   0,  NULL    },
+	{ "outlet.group.3.name",            628,    8,  APC_VT_STRING,   APC_VF_RW, NULL,                                           "%s",   0,  NULL    },
+	{ NULL, 0, 0, 0, 0, NULL, NULL, 0.0f, NULL }
 };
 
 static apc_modbus_register_t apc_modbus_register_map_status[] = {
-	{ "input.transfer.reason",      2,      1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_status_change_cause_conversion,    NULL,   0,  NULL    },
-	{ NULL, 0, 0, 0, NULL, NULL, 0.0f, NULL }
+	{ "input.transfer.reason",          2,      1,  APC_VT_UINT,     0,         &_apc_modbus_status_change_cause_conversion,    NULL,   0,  NULL    },
+	{ "ups.test.result",          		23,     1,  APC_VT_UINT,     0,         &_apc_modbus_battery_test_status_conversion,    NULL,   0,  NULL    },
+	{ NULL, 0, 0, 0, 0, NULL, NULL, 0.0f, NULL }
 };
 
 static apc_modbus_register_t apc_modbus_register_map_dynamic[] = {
-	{ "battery.runtime",            128,    2,  APC_MODBUS_VALUE_TYPE_UINT,     NULL,                                           "%u",   0,  NULL    },
-	{ "battery.charge",             130,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.2f", 9,  NULL    },
-	{ "battery.voltage",            131,    1,  APC_MODBUS_VALUE_TYPE_INT,      &_apc_modbus_double_conversion,                 "%.2f", 5,  NULL    },
-	{ "battery.date.maintenance",   133,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
-	{ "battery.temperature",        135,    1,  APC_MODBUS_VALUE_TYPE_INT,      &_apc_modbus_double_conversion,                 "%.2f", 7,  NULL    },
-	{ "ups.load",                   136,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.2f", 8,  NULL    },
-	{ "ups.realpower",              136,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_power_conversion,                  "%.2f", 8,  &realpower_nominal },
-	{ "ups.power",                  138,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_power_conversion,                  "%.2f", 8,  &power_nominal     },
-	{ "output.current",             140,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.2f", 5,  NULL    },
-	{ "output.voltage",             142,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.2f", 6,  NULL    },
-	{ "output.frequency",           144,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_double_conversion,                 "%.2f", 7,  NULL    },
-	{ "experimental.output.energy", 145,    2,  APC_MODBUS_VALUE_TYPE_UINT,     NULL,                                           "%u",   0,  NULL    },
-	{ "input.voltage",              151,    1,  APC_MODBUS_VALUE_TYPE_UINT,     &_apc_modbus_voltage_conversion,                "%.2f", 6,  NULL    },
-	{ "ups.efficiency",             154,    1,  APC_MODBUS_VALUE_TYPE_INT,      &_apc_modbus_efficiency_conversion,             "%.1f", 7,  NULL    },
-	{ "ups.timer.shutdown",         155,    1,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ "ups.timer.start",            156,    1,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ "ups.timer.reboot",           157,    2,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ NULL, 0, 0, 0, NULL, NULL, 0.0f, NULL }
+	{ "battery.runtime",                128,    2,  APC_VT_UINT,     0,         NULL,                                           "%u",   0,  NULL    },
+	{ "battery.charge",                 130,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.2f", 9,  NULL    },
+	{ "battery.voltage",                131,    1,  APC_VT_INT,      0,         &_apc_modbus_double_conversion,                 "%.2f", 5,  NULL    },
+	{ "battery.date.maintenance",       133,    1,  APC_VT_UINT,     0,         &_apc_modbus_date_conversion,                   NULL,   0,  NULL    },
+	{ "battery.temperature",            135,    1,  APC_VT_INT,      0,         &_apc_modbus_double_conversion,                 "%.2f", 7,  NULL    },
+	{ "ups.load",                       136,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.2f", 8,  NULL    },
+	{ "ups.realpower",                  136,    1,  APC_VT_UINT,     0,         &_apc_modbus_power_conversion,                  "%.2f", 8,  &realpower_nominal },
+	{ "ups.power",                      138,    1,  APC_VT_UINT,     0,         &_apc_modbus_power_conversion,                  "%.2f", 8,  &power_nominal     },
+	{ "output.current",                 140,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.2f", 5,  NULL    },
+	{ "output.voltage",                 142,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.2f", 6,  NULL    },
+	{ "output.frequency",               144,    1,  APC_VT_UINT,     0,         &_apc_modbus_double_conversion,                 "%.2f", 7,  NULL    },
+	{ "experimental.output.energy",     145,    2,  APC_VT_UINT,     0,         NULL,                                           "%u",   0,  NULL    },
+	{ "input.voltage",                  151,    1,  APC_VT_UINT,     0,         &_apc_modbus_voltage_conversion,                "%.2f", 6,  NULL    },
+	{ "ups.efficiency",                 154,    1,  APC_VT_INT,      0,         &_apc_modbus_efficiency_conversion,             "%.1f", 7,  NULL    },
+	{ "ups.timer.shutdown",             155,    1,  APC_VT_INT,      0,         NULL,                                           "%d",   0,  NULL    },
+	{ "ups.timer.start",                156,    1,  APC_VT_INT,      0,         NULL,                                           "%d",   0,  NULL    },
+	{ "ups.timer.reboot",               157,    2,  APC_VT_INT,      0,         NULL,                                           "%d",   0,  NULL    },
+	{ NULL, 0, 0, 0, 0, NULL, NULL, 0.0f, NULL }
 };
 
 static apc_modbus_register_t apc_modbus_register_map_static[] = {
-	{ "input.transfer.high",        1026,   1,  APC_MODBUS_VALUE_TYPE_UINT,     NULL,                                           "%u",   0,  NULL    },
-	{ "input.transfer.low",         1027,   1,  APC_MODBUS_VALUE_TYPE_UINT,     NULL,                                           "%u",   0,  NULL    },
-	{ "ups.delay.shutdown",         1029,   1,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ "ups.delay.start",            1030,   1,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ "ups.delay.reboot",           1031,   2,  APC_MODBUS_VALUE_TYPE_INT,      NULL,                                           "%d",   0,  NULL    },
-	{ NULL, 0, 0, 0, NULL, NULL, 0.0f, NULL }
+	{ "input.transfer.high",            1026,   1,  APC_VT_UINT,     APC_VF_RW, NULL,                                           "%u",   0,  NULL    },
+	{ "input.transfer.low",             1027,   1,  APC_VT_UINT,     APC_VF_RW, NULL,                                           "%u",   0,  NULL    },
+	{ "ups.delay.shutdown",             1029,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "ups.delay.start",                1030,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "ups.delay.reboot",               1031,   2,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.0.delay.shutdown",  1029,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.0.delay.start",     1030,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.0.delay.reboot",    1031,   2,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.1.delay.shutdown",  1034,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.1.delay.start",     1035,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.1.delay.reboot",    1036,   2,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.2.delay.shutdown",  1039,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.2.delay.start",     1040,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.2.delay.reboot",    1041,   2,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.3.delay.shutdown",  1044,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.3.delay.start",     1045,   1,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ "outlet.group.3.delay.reboot",    1046,   2,  APC_VT_INT,      APC_VF_RW, NULL,                                           "%d",   0,  NULL    },
+	{ NULL, 0, 0, 0, 0, NULL, NULL, 0.0f, NULL }
+};
+
+static apc_modbus_register_t* apc_modbus_register_maps[] = {
+	apc_modbus_register_map_inventory,
+	apc_modbus_register_map_status,
+	apc_modbus_register_map_dynamic,
+	apc_modbus_register_map_static
 };
 
 static void _apc_modbus_close(int free_modbus)
@@ -757,6 +1050,7 @@ static int _apc_modbus_update_value(apc_modbus_register_t *regs_info, const uint
 {
 	apc_modbus_value_t value;
 	char strbuf[33], nutvbuf[128];
+	int dstate_flags;
 
 	if (regs_info == NULL || regs == NULL || regs_len == 0) {
 		/* Invalid parameters */
@@ -770,19 +1064,44 @@ static int _apc_modbus_update_value(apc_modbus_register_t *regs_info, const uint
 
 	assert(regs_info->value_type <= apc_modbus_value_types_max);
 	switch (regs_info->value_type) {
-	case APC_MODBUS_VALUE_TYPE_STRING:
+	case APC_VT_STRING:
 		_apc_modbus_to_string(regs, regs_info->modbus_len, strbuf, sizeof(strbuf));
 		value.data.string_value = strbuf;
 		break;
-	case APC_MODBUS_VALUE_TYPE_INT:
+	case APC_VT_INT:
 		_apc_modbus_to_int64(regs, regs_info->modbus_len, &value.data.int_value);
 		break;
-	case APC_MODBUS_VALUE_TYPE_UINT:
+	case APC_VT_UINT:
 		_apc_modbus_to_uint64(regs, regs_info->modbus_len, &value.data.uint_value);
 		break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+	default:
+		/* Must not occur. */
+		break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
-	if (regs_info->value_converter != NULL) {
+	if (regs_info->value_converter != NULL && regs_info->value_converter->apc_to_nut != NULL) {
 		/* If we have a converter, use it and set the value as a string */
 		if (!regs_info->value_converter->apc_to_nut(&value, nutvbuf, sizeof(nutvbuf))) {
 			upslogx(LOG_ERR, "%s: Failed to convert register %" PRIuSIZE ":%" PRIuSIZE, __func__,
@@ -799,21 +1118,58 @@ static int _apc_modbus_update_value(apc_modbus_register_t *regs_info, const uint
 #endif
 		assert(regs_info->value_type <= apc_modbus_value_types_max);
 		switch (regs_info->value_type) {
-		case APC_MODBUS_VALUE_TYPE_STRING:
+		case APC_VT_STRING:
 			dstate_setinfo(regs_info->nut_variable_name, regs_info->value_format, value.data.string_value);
 			break;
-		case APC_MODBUS_VALUE_TYPE_INT:
+		case APC_VT_INT:
 			dstate_setinfo(regs_info->nut_variable_name, regs_info->value_format, value.data.int_value);
 			break;
-		case APC_MODBUS_VALUE_TYPE_UINT:
+		case APC_VT_UINT:
 			dstate_setinfo(regs_info->nut_variable_name, regs_info->value_format, value.data.uint_value);
 			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 		}
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_NONLITERAL
 #pragma GCC diagnostic pop
 #endif
 	}
 
+	dstate_flags = 0;
+	if (regs_info->value_type == APC_VT_STRING) {
+		dstate_flags |= ST_FLAG_STRING;
+	}
+	if ((regs_info->value_flags & APC_VF_RW)) {
+		dstate_flags |= ST_FLAG_RW;
+	}
+	dstate_setflags(regs_info->nut_variable_name, dstate_flags);
+	if (regs_info->value_type == APC_VT_STRING) {
+		dstate_setaux(regs_info->nut_variable_name, regs_info->modbus_len * sizeof(uint16_t));
+	}
+
 	return 1;
 }
 
@@ -837,11 +1193,38 @@ static int _apc_modbus_process_registers(apc_modbus_register_t* values, const ui
 
 static int _apc_modbus_read_inventory(void)
 {
-	uint16_t regbuf[88];
+	uint16_t regbuf[120];
+	int start_addr;
+	uint16_t sog_relay_config;
+	int outlet_group_count;
 
 	/* Inventory Information */
-	if (_apc_modbus_read_registers(modbus_ctx, 516, 88, regbuf)) {
-		_apc_modbus_process_registers(apc_modbus_register_map_inventory, regbuf, 88, 516);
+	start_addr = apc_modbus_register_map_inventory[0].modbus_addr;
+	if (_apc_modbus_read_registers(modbus_ctx, start_addr, SIZEOF_ARRAY(regbuf), regbuf)) {
+		sog_relay_config = regbuf[APC_MODBUS_SOGRELAYCONFIGSETTING_BF_REG - start_addr];
+
+		outlet_group_count = 0;
+		if ((sog_relay_config & APC_MODBUS_SOGRELAYCONFIGSETTING_BF_MOG_PRESENT)) {
+			outlet_group_count++;
+		}
+		if ((sog_relay_config & APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_0_PRESENT)) {
+			outlet_group_count++;
+		}
+		if ((sog_relay_config & APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_1_PRESENT)) {
+			outlet_group_count++;
+		}
+		if ((sog_relay_config & APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_2_PRESENT)) {
+			outlet_group_count++;
+		}
+		/* Documentation says there is a bit for SOG3, but everything else does not have it */
+		if ((sog_relay_config & APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_3_PRESENT)) {
+			upslogx(LOG_WARNING, "%s: SOG3 present, but we don't know how to use it", __func__);
+			outlet_group_count++;
+		}
+
+		dstate_setinfo("outlet.group.count", "%d", outlet_group_count);
+
+		_apc_modbus_process_registers(apc_modbus_register_map_inventory, regbuf, SIZEOF_ARRAY(regbuf), start_addr);
 	} else {
 		return 0;
 	}
@@ -849,8 +1232,218 @@ static int _apc_modbus_read_inventory(void)
 	return 1;
 }
 
+static int _apc_modbus_setvar(const char *nut_varname, const char *str_value)
+{
+	size_t mi, i;
+	int addr, nb, r;
+	apc_modbus_register_t *apc_map = NULL, *apc_value = NULL;
+	uint16_t reg_value[16];
+
+	for (mi = 0; mi < SIZEOF_ARRAY(apc_modbus_register_maps) && apc_value == NULL; mi++) {
+		apc_map = apc_modbus_register_maps[mi];
+
+		for (i = 0; apc_map[i].nut_variable_name; i++) {
+			if (!strcasecmp(nut_varname, apc_map[i].nut_variable_name)) {
+				apc_value = &apc_map[i];
+				break;
+			}
+		}
+	}
+
+	if (!apc_map || !apc_value) {
+		upslogx(LOG_WARNING, "%s: [%s] is unknown", __func__, nut_varname);
+		return STAT_SET_UNKNOWN;
+	}
+
+	if (!(apc_value->value_flags & APC_VF_RW)) {
+		upslogx(LOG_WARNING, "%s: [%s] is not writable", __func__, nut_varname);
+		return STAT_SET_INVALID;
+	}
+
+	assert(apc_value->modbus_len < SIZEOF_ARRAY(reg_value));
+
+	if (apc_value->value_converter && apc_value->value_converter->nut_to_apc) {
+		if (!apc_value->value_converter->nut_to_apc(str_value, reg_value, apc_value->modbus_len)) {
+			upslogx(LOG_WARNING, "%s: [%s] failed to convert value", __func__, nut_varname);
+			return STAT_SET_CONVERSION_FAILED;
+		}
+	} else {
+		assert(apc_value->value_type <= apc_modbus_value_types_max);
+		switch (apc_value->value_type) {
+		case APC_VT_STRING:
+			r = _apc_modbus_from_string(str_value, reg_value, apc_value->modbus_len);
+			break;
+		case APC_VT_INT:
+			r = _apc_modbus_from_int64_string(str_value, reg_value, apc_value->modbus_len);
+			break;
+		case APC_VT_UINT:
+			r = _apc_modbus_from_uint64_string(str_value, reg_value, apc_value->modbus_len);
+			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
+		}
+
+		if (!r) {
+			upslogx(LOG_WARNING, "%s: [%s] failed to convert value", __func__, nut_varname);
+			return STAT_SET_CONVERSION_FAILED;
+		}
+	}
+
+	addr = apc_value->modbus_addr;
+	nb = apc_value->modbus_len;
+	if (modbus_write_registers(modbus_ctx, addr, nb, reg_value) < 0) {
+		upslogx(LOG_ERR, "%s: Write of %d:%d failed: %s (%s)", __func__, addr, addr + nb, modbus_strerror(errno), device_path);
+		_apc_modbus_handle_error(modbus_ctx);
+		return STAT_SET_FAILED;
+	}
+
+	/* There seem to be some communication problems if we don't wait after writing.
+	 * Maybe there is some register we need to poll for write completion?
+	 */
+	usleep(100000);
+
+	upslogx(LOG_INFO, "SET %s='%s'", nut_varname, str_value);
+
+	if (_apc_modbus_read_registers(modbus_ctx, addr, nb, reg_value)) {
+		_apc_modbus_process_registers(apc_map, reg_value, nb, addr);
+	}
+
+	return STAT_SET_HANDLED;
+}
+
+typedef struct {
+	const char *nut_command_name;
+	size_t modbus_addr;
+	size_t modbus_len; /* Number of uint16_t registers */
+	uint64_t value;
+} apc_modbus_command_t;
+
+static apc_modbus_command_t apc_modbus_command_map[] = {
+	{ "test.battery.start",         APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_REG,    1,  APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_START   },
+	{ "test.battery.stop",          APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_REG,    1,  APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_ABORT   },
+	{ "test.panel.start",           APC_MODBUS_USERINTERFACECOMMAND_BF_REG,         1,  APC_MODBUS_USERINTERFACECOMMAND_BF_SHORT_TEST   },
+	{ "calibrate.start",            APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_REG,    1,  APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_START   },
+	{ "calibrate.stop",             APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_REG,    1,  APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_ABORT   },
+	{ "bypass.start",               APC_MODBUS_UPSCOMMAND_BF_REG,                   2,  APC_MODBUS_UPSCOMMAND_BF_OUTPUT_INTO_BYPASS     },
+	{ "bypass.stop",                APC_MODBUS_UPSCOMMAND_BF_REG,                   2,  APC_MODBUS_UPSCOMMAND_BF_OUTPUT_OUT_OF_BYPASS   },
+	{ "beeper.mute",                APC_MODBUS_USERINTERFACECOMMAND_BF_REG,         1,  APC_MODBUS_USERINTERFACECOMMAND_BF_MUTE_ALL_ACTIVE_AUDIBLE_ALARMS },
+	{ "load.off",                   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "load.on",                    APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "load.off.delay",             APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "load.on.delay",              APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_ON_DELAY },
+	{ "shutdown.return",            APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "shutdown.stayoff",           APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "shutdown.reboot",            APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "shutdown.reboot.graceful",   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "outlet.0.shutdown.return",   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "outlet.0.load.off",          APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "outlet.0.load.on",           APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "outlet.0.load.cycle",        APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP },
+	{ "outlet.1.shutdown.return",   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_0 | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "outlet.1.load.off",          APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_0 },
+	{ "outlet.1.load.on",           APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_0 },
+	{ "outlet.1.load.cycle",        APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_0 },
+	{ "outlet.2.shutdown.return",   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_1 | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "outlet.2.load.off",          APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_1 },
+	{ "outlet.2.load.on",           APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_1 },
+	{ "outlet.2.load.cycle",        APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_1 },
+	{ "outlet.3.shutdown.return",   APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_2 | APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY },
+	{ "outlet.3.load.off",          APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_2 },
+	{ "outlet.3.load.on",           APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_2 },
+	{ "outlet.3.load.cycle",        APC_MODBUS_OUTLETCOMMAND_BF_REG,                2,
+		APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_2 },
+	{ NULL, 0, 0, 0 }
+};
+
+static int _apc_modbus_instcmd(const char *nut_cmdname, const char *extra)
+{
+	size_t i;
+	int addr, nb;
+	apc_modbus_command_t *apc_command = NULL;
+	uint16_t value[4]; /* Max 64-bit */
+
+	NUT_UNUSED_VARIABLE(extra);
+
+	for (i = 0; apc_modbus_command_map[i].nut_command_name; i++) {
+		if (!strcasecmp(nut_cmdname, apc_modbus_command_map[i].nut_command_name)) {
+			apc_command = &apc_modbus_command_map[i];
+			break;
+		}
+	}
+
+	if (!apc_command) {
+		upslogx(LOG_WARNING, "%s: [%s] is unknown", __func__, nut_cmdname);
+		return STAT_INSTCMD_UNKNOWN;
+	}
+
+	assert(apc_command->modbus_len <= SIZEOF_ARRAY(value));
+
+	if (!_apc_modbus_from_uint64(apc_command->value, value, apc_command->modbus_len)) {
+		upslogx(LOG_WARNING, "%s: [%s] failed to convert value", __func__, nut_cmdname);
+		return STAT_INSTCMD_CONVERSION_FAILED;
+	}
+
+	addr = apc_command->modbus_addr;
+	nb = apc_command->modbus_len;
+	if (modbus_write_registers(modbus_ctx, addr, nb, value) < 0) {
+		upslogx(LOG_ERR, "%s: Write of %d:%d failed: %s (%s)", __func__, addr, addr + nb, modbus_strerror(errno), device_path);
+		_apc_modbus_handle_error(modbus_ctx);
+		return STAT_INSTCMD_FAILED;
+	}
+
+	return STAT_INSTCMD_HANDLED;
+}
+
 void upsdrv_initinfo(void)
 {
+	size_t i;
+
 	if (!_apc_modbus_read_inventory()) {
 		fatalx(EXIT_FAILURE, "Can't read inventory information from the UPS");
 	}
@@ -858,6 +1451,14 @@ void upsdrv_initinfo(void)
 	dstate_setinfo("ups.mfr", "American Power Conversion"); /* also device.mfr, filled automatically */
 
 	dstate_setinfo("device.type", "ups");
+
+	for (i = 0; apc_modbus_command_map[i].nut_command_name; i++) {
+		dstate_addcmd(apc_modbus_command_map[i].nut_command_name);
+	}
+
+	upsh.setvar = _apc_modbus_setvar;
+	upsh.instcmd = _apc_modbus_instcmd;
+
 }
 
 void upsdrv_updateinfo(void)
@@ -950,8 +1551,8 @@ void upsdrv_updateinfo(void)
 	}
 
 	/* Static Data */
-	if (_apc_modbus_read_registers(modbus_ctx, 1026, 7, regbuf)) {
-		_apc_modbus_process_registers(apc_modbus_register_map_static, regbuf, 7, 1026);
+	if (_apc_modbus_read_registers(modbus_ctx, 1026, 22, regbuf)) {
+		_apc_modbus_process_registers(apc_modbus_register_map_static, regbuf, 22, 1026);
 	} else {
 		dstate_datastale();
 		return;
@@ -964,9 +1565,7 @@ void upsdrv_updateinfo(void)
 
 void upsdrv_shutdown(void)
 {
-	/* TODO: replace with a proper shutdown function */
-	upslogx(LOG_ERR, "shutdown not supported");
-	set_exit_flag(-1);
+	modbus_write_register(modbus_ctx, APC_MODBUS_OUTLETCOMMAND_BF_REG, APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN | APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP);
 }
 
 void upsdrv_help(void)
@@ -1341,6 +1940,9 @@ void upsdrv_initups(void)
 	}
 
 #if defined NUT_MODBUS_HAS_USB
+	/* This creates an exact matcher after the first connection so that on
+	 * reconnect we are more likely to match the exact device we connected to
+	 * the first time. */
 	_apc_modbus_create_reopen_matcher();
 #endif /* defined NUT_MODBUS_HAS_USB */
 
diff --git a/drivers/apc_modbus.h b/drivers/apc_modbus.h
new file mode 100644
index 0000000000..d175eb4974
--- /dev/null
+++ b/drivers/apc_modbus.h
@@ -0,0 +1,91 @@
+/*  apc_modbus.h - Driver for APC Modbus UPS
+ *  Copyright © 2023 Axel Gembe <axel@gembe.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef APC_MODBUS_H
+#define APC_MODBUS_H
+
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_PENDING (1 << 0)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_INPROGRESS (1 << 1)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_PASSED (1 << 2)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_FAILED (1 << 3)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_REFUSED (1 << 4)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_ABORTED (1 << 5)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_PROTOCOL (1 << 6)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_LOCALUI (1 << 7)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_SOURCE_INTERNAL (1 << 8)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_INVALIDSTATE (1 << 9)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_INTERNALFAULT (1 << 10)
+#define APC_MODBUS_REPLACEBATTERYTESTSTATUS_BF_MOD_STATEOFCHARGENOTACCEPTABLE (1 << 11)
+
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_REG 590
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_MOG_PRESENT (1 << 0)
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_0_PRESENT (1 << 1)
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_1_PRESENT (1 << 2)
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_2_PRESENT (1 << 3)
+#define APC_MODBUS_SOGRELAYCONFIGSETTING_BF_SOG_3_PRESENT (1 << 4)
+
+#define APC_MODBUS_UPSCOMMAND_BF_REG 1536
+/* 0 - 2 are reserved */
+#define APC_MODBUS_UPSCOMMAND_BF_RESTORE_FACTORY_SETTINGS (1 << 3)
+#define APC_MODBUS_UPSCOMMAND_BF_OUTPUT_INTO_BYPASS (1 << 4)
+#define APC_MODBUS_UPSCOMMAND_BF_OUTPUT_OUT_OF_BYPASS (1 << 5)
+/* 6 - 8 are reserved */
+#define APC_MODBUS_UPSCOMMAND_BF_CLEAR_FAULTS (1 << 9)
+/* 10 - 12 are reserved */
+#define APC_MODBUS_UPSCOMMAND_BF_RESET_STRINGS (1 << 13)
+#define APC_MODBUS_UPSCOMMAND_BF_RESET_LOGS (1 << 14)
+
+#define APC_MODBUS_OUTLETCOMMAND_BF_REG 1538
+#define APC_MODBUS_OUTLETCOMMAND_BF_CMD_CANCEL						(1 << 0)
+#define APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_ON					(1 << 1)
+#define APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_OFF					(1 << 2)
+#define APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_SHUTDOWN				(1 << 3)
+#define APC_MODBUS_OUTLETCOMMAND_BF_CMD_OUTPUT_REBOOT				(1 << 4)
+#define APC_MODBUS_OUTLETCOMMAND_BF_MOD_COLD_BOOT_ALLOWED			(1 << 5)
+#define APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_ON_DELAY				(1 << 6)
+#define APC_MODBUS_OUTLETCOMMAND_BF_MOD_USE_OFF_DELAY				(1 << 7)
+#define APC_MODBUS_OUTLETCOMMAND_BF_TARGET_MAIN_OUTLET_GROUP		(1 << 8)
+#define APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_0	(1 << 9)
+#define APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_1	(1 << 10)
+#define APC_MODBUS_OUTLETCOMMAND_BF_TARGET_SWITCHED_OUTLET_GROUP_2	(1 << 11)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_USB_PORT					(1 << 12)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_LOCAL_USER				(1 << 13)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_RJ45_PORT				(1 << 14)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_SMART_SLOT_1				(1 << 15)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_SMART_SLOT_2				(1 << 16)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_INTERNAL_NETWORK_1		(1 << 17)
+#define APC_MODBUS_OUTLETCOMMAND_BF_SOURCE_INTERNAL_NETWORK_2		(1 << 18)
+
+#define APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_REG 1541
+#define APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_START	(1 << 0)
+#define APC_MODBUS_REPLACEBATTERYTESTCOMMAND_BF_ABORT	(1 << 1)
+
+#define APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_REG 1542
+#define APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_START	(1 << 0)
+#define APC_MODBUS_RUNTIMECALIBRATIONCOMMAND_BF_ABORT	(1 << 1)
+
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_REG 1543
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_SHORT_TEST						(1 << 0)
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_CONTINUOUS_TEST					(1 << 1)
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_MUTE_ALL_ACTIVE_AUDIBLE_ALARMS	(1 << 2)
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_CANCEL_MUTE						(1 << 3)
+/* 4 is reserved */
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_ACKNOWLEDGE_BATTERY_ALARMS		(1 << 5)
+#define APC_MODBUS_USERINTERFACECOMMAND_BF_ACKNOWLEDGE_SITE_WIRING_ALARM	(1 << 6)
+
+#endif /* APC_MODBUS_H */
diff --git a/drivers/apcsmart-old.c b/drivers/apcsmart-old.c
index 9771e0e52a..5a56c99106 100644
--- a/drivers/apcsmart-old.c
+++ b/drivers/apcsmart-old.c
@@ -118,6 +118,9 @@ static const char *convert_data(apc_vartab_t *cmd_entry, const char *upsval)
 				case 'S': return "simulated power failure or UPS test";
 				default: return upsval;
 			}
+
+		default:
+			break;
 	}
 
 	upslogx(LOG_NOTICE, "Unable to handle conversion of %s", cmd_entry->name);
diff --git a/drivers/apcsmart.c b/drivers/apcsmart.c
index 97b488bc46..54c04dcda7 100644
--- a/drivers/apcsmart.c
+++ b/drivers/apcsmart.c
@@ -4,6 +4,7 @@
  * Copyright (C) 1999  Russell Kroll <rkroll@exploits.org>
  *           (C) 2000  Nigel Metheringham <Nigel.Metheringham@Intechnology.co.uk>
  *           (C) 2011+ Michal Soltys <soltys@ziu.info>
+ *           (C) 2024  Jim Klimov <jimklimov+nut@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -36,7 +37,7 @@
 #include "apcsmart_tabs.h"
 
 #define DRIVER_NAME	"APC Smart protocol driver"
-#define DRIVER_VERSION	"3.32"
+#define DRIVER_VERSION	"3.34"
 
 #ifdef WIN32
 # ifndef ECANCELED
@@ -87,7 +88,7 @@ static int (*sdlist[])(const void *) = {
 /*
  * note: both lookup functions MUST be used after variable detection is
  * completed - that is after deprecate_vars() call; the general reason for this
- * is 1:n and n:1 nut <-> apc mappings, which are not determined prior to the
+ * is 1:n and n:1 NUT <-> APC mappings, which are not determined prior to the
  * detection
  */
 static apc_vartab_t *vt_lookup_char(char cmdchar)
@@ -148,6 +149,8 @@ static const char *convert_data(apc_vartab_t *vt, const char *upsval)
 	static char temp[APC_LBUF];
 	long tval;
 
+	memset(temp, '\0', sizeof(temp));
+
 	/* this should never happen */
 	if (strlen(upsval) >= sizeof(temp)) {
 		upslogx(LOG_CRIT, "%s: the length of [%s] is too big", __func__, vt->name);
@@ -166,7 +169,8 @@ static const char *convert_data(apc_vartab_t *vt, const char *upsval)
 		case APC_F_SECONDS:
 		case APC_F_LEAVE:
 			/* no conversion for any of these */
-			strcpy(temp, upsval);
+			strncpy(temp, upsval, sizeof(temp) - 1);
+			temp[sizeof(temp) - 1] = '\0';
 			return temp;
 
 		case APC_F_HOURS:
@@ -193,21 +197,26 @@ static const char *convert_data(apc_vartab_t *vt, const char *upsval)
 				case 'O': return "no transfers yet since turnon";
 				case 'S': return "simulated power failure or UPS test";
 				default:
-					  strcpy(temp, upsval);
-					  return temp;
+					strncpy(temp, upsval, sizeof(temp) - 1);
+					temp[sizeof(temp) - 1] = '\0';
+					return temp;
 			}
+
+		default:
+			break;
 	}
 
 	/* this should never happen */
 	upslogx(LOG_CRIT, "%s: unable to convert [%s]", __func__, vt->name);
-	strcpy(temp, upsval);
+	strncpy(temp, upsval, sizeof(temp) - 1);
+	temp[sizeof(temp) - 1] = '\0';
 	return temp;
 }
 
 /* report differences if tcsetattr != tcgetattr, return otherwise */
 
 /*
- * Aix compatible names
+ * AIX compatible names
  */
 #if defined(VWERSE) && !defined(VWERASE)
 #define VWERASE VWERSE
@@ -276,7 +285,7 @@ static void apc_ser_diff(struct termios *tioset, struct termios *tioget)
 	upslogx(LOG_NOTICE, "%s: device reports different attributes than requested", device_path);
 
 	/*
-	 * According to the manual the most common problem is mis-matched
+	 * According to the manual the most common problem is mismatched
 	 * combinations of input and output baud rates. If the combination is
 	 * not supported then neither are changed. This should not be a
 	 * problem here since we set them both to the same extremely common
@@ -284,12 +293,18 @@ static void apc_ser_diff(struct termios *tioset, struct termios *tioget)
 	 */
 
 	for (i = 0; i < SIZEOF_ARRAY(tio); i++) {
-		upsdebugx(1, "tc%cetattr(): gfmt1:cflag=%x:iflag=%x:lflag=%x:oflag=%x:", dir[i],
-				(unsigned int) tio[i]->c_cflag, (unsigned int) tio[i]->c_iflag,
-				(unsigned int) tio[i]->c_lflag, (unsigned int) tio[i]->c_oflag);
+		upsdebugx(1,
+			"%s: tc%cetattr(): gfmt1:cflag=%x:iflag=%x:lflag=%x:oflag=%x:",
+			__func__, dir[i],
+			(unsigned int) tio[i]->c_cflag, (unsigned int) tio[i]->c_iflag,
+			(unsigned int) tio[i]->c_lflag, (unsigned int) tio[i]->c_oflag);
 		for (cp = cchars1; cp->name; ++cp)
-			upsdebugx(1, "\t%s=%x:", cp->name, tio[i]->c_cc[cp->sub]);
-		upsdebugx(1, "\tispeed=%d:ospeed=%d", (int) cfgetispeed(tio[i]), (int) cfgetospeed(tio[i]));
+			upsdebugx(1, "%s: \t%s=%x:",
+				__func__, cp->name, tio[i]->c_cc[cp->sub]);
+		upsdebugx(1, "%s: \tispeed=%d:ospeed=%d",
+			__func__,
+			(int) cfgetispeed(tio[i]),
+			(int) cfgetospeed(tio[i]));
 	}
 }
 
@@ -441,7 +456,7 @@ static void alert_handler(char ch)
 }
 
 /*
- * we need a tiny bit different processing due to '*' and canonical mode; the
+ * we need a tiny bit different processing due to "*" and canonical mode; the
  * function is subtly different from generic ser_get_line_alert()
  */
 #define apc_read(b, l, f) apc_read_i(b, l, f, __func__, __LINE__)
@@ -506,10 +521,10 @@ static ssize_t apc_read_i(char *buf, size_t buflen, int flags, const char *fn, u
 				ser_comm_fail("serial port read timeout: %u(%s)", ln, fn);
 			return ret;
 		}
-		/* ok, timeout is acceptable */
+		/* ok, timeout is acceptable... */
 		if (ret == 0 && (flags & SER_TO)) {
 			/*
-			 * but it doesn't imply ser_comm_good
+			 * ...but it doesn't imply ser_comm_good
 			 *
 			 * for example we might be in comm_fail condition,
 			 * trying to "nudge" the UPS with some command
@@ -535,17 +550,18 @@ static ssize_t apc_read_i(char *buf, size_t buflen, int flags, const char *fn, u
 				return (ssize_t)count;
 			}
 			/*
-			 * '*' is set as a secondary EOL; convert to 'OK' only as a
-			 * reply to shutdown command in sdok(); otherwise next
-			 * select_read() will continue normally
+			 * "*" is set as a secondary EOL; convert to "OK" only
+			 * as a reply to shutdown command in sdok(); otherwise
+			 * next select_read() will continue normally
 			 */
 			if ((flags & SER_HA) && temp[i] == '*') {
 				/*
-				 * a bit paranoid, but remember '*' is not real EOL;
-				 * there could be some firmware in existence, that
-				 * would send both string: 'OK\n' and alert: '*'.
-				 * Just in case, try to flush the input with small 1 sec.
-				 * timeout
+				 * a bit paranoid, but remember that "*" is not
+				 * real EOL; there could be some firmware in
+				 * existence, which would send both string:
+				 * "OK\n" and alert: "*".
+				 * Just in case, try to flush the input with a
+				 * small 1 sec timeout.
 				 */
 				memset(buf, '\0', buflen);
 				errno = 0;
@@ -589,9 +605,9 @@ static ssize_t apc_write_i(unsigned char code, const char *fn, unsigned int ln)
 
 	ret = ser_send_char(upsfd, code);
 	/*
-	 * Formally any write() sould never return 0, if the count != 0. For
+	 * Formally any write() should never return 0, if the count != 0. For
 	 * the sake of handling any obscure nonsense, we consider such return
-	 * as a failure - thus <= condition; either way, LE is pretty hard
+	 * as a failure - thus <= condition; either way, LE is a pretty hard
 	 * condition hardly ever happening;
 	 */
 	if (ret <= 0)
@@ -603,7 +619,7 @@ static ssize_t apc_write_i(unsigned char code, const char *fn, unsigned int ln)
 /*
  * We have to watch out for NA, here;
  * This is generally safe, as otherwise we will just timeout. The reason we do
- * it, is that under certain conditions an ups might respond with NA for
+ * it, is that under certain conditions an UPS might respond with NA for
  * something it would normally handle (e.g. calling @ while being in powered
  * off or hibernated state. If we keep sending the "arguments" after getting
  * NA, they will be interpreted as commands, which is quite a bug :)
@@ -677,7 +693,7 @@ static void apc_flush(int flags)
 	}
 }
 
-/* apc specific wrappers around set/del info - to handle "packed" variables */
+/* APC specific wrappers around set/del info - to handle "packed" variables */
 static void apc_dstate_delinfo(apc_vartab_t *vt, int skip)
 {
 	char *name, *nidx;
@@ -694,7 +710,9 @@ static void apc_dstate_delinfo(apc_vartab_t *vt, int skip)
 		return;
 	}
 
-	strcpy(name, vt->name);
+	memset(name, '\0', vt->nlen0);
+	strncpy(name, vt->name, vt->nlen0 - 1);
+	name[vt->nlen0 - 1] = '\0';
 	nidx = strstr(name,".0.") + 1;
 
 	for (c = skip; c < vt->cnt; c++) {
@@ -710,6 +728,7 @@ static void apc_dstate_setinfo(apc_vartab_t *vt, const char *upsval)
 {
 	char *name, *nidx;
 	char *temp, *vidx[APC_PACK_MAX], *com, *curr;
+	size_t upsvallen = strlen(upsval);
 	int c;
 
 	/* standard not packed var */
@@ -723,18 +742,23 @@ static void apc_dstate_setinfo(apc_vartab_t *vt, const char *upsval)
 		return;
 	}
 
-	if ( !(temp = xmalloc(sizeof(char) * (strlen(upsval) + 1))) ) {
+	if ( !(temp = xmalloc(sizeof(char) * (upsvallen + 2))) ) {
+		/* +2 seems like an overkill, but helps hush compiler warnings */
 		upslogx(LOG_ERR, "apc_dstate_setinfo() failed to allocate buffer");
 		free(name);
 		return;
 	}
 
 	/* we have to set proper name for dstate_setinfo() calls */
-	strcpy(name, vt->name);
+	memset(name, '\0', vt->nlen0);
+	strncpy(name, vt->name, vt->nlen0 - 1);
+	name[vt->nlen0 - 1] = '\0';
 	nidx = strstr(name,".0.") + 1;
 
 	/* split the value string */
-	strcpy(temp, upsval);
+	memset(temp, '\0', upsvallen + 2);
+	strncpy(temp, upsval, upsvallen + 1);
+	temp[upsvallen] = '\0';
 	curr = temp;
 	c = 0;
 	do {
@@ -905,10 +929,10 @@ static int var_verify(apc_vartab_t *vt)
 }
 
 /*
- * This function iterates over vartab, deprecating nut<->apc 1:n and n:1
+ * This function iterates over vartab, deprecating NUT<->APC 1:n and n:1
  * variables. We prefer earliest present variable. All the other ones must be
  * marked as not present (which implies deprecation).
- * This pass is requried after completion of all protocol_verify() and/or
+ * This pass is required after completion of all protocol_verify() and/or
  * legacy_verify() calls.
  */
 static void deprecate_vars(void)
@@ -978,7 +1002,7 @@ static void apc_getcaps(int qco)
 
 	/*
 	 * note - apc_read() needs larger timeout grace (not a problem w.r.t.
-	 * to nut's timing, as it's done only during setup) and different
+	 * to NUT's timing, as it's done only during setup) and different
 	 * ignore set due to certain characters like '#' being received
 	 */
 	ret = apc_read(temp, sizeof(temp), SER_CC|SER_TO);
@@ -1001,7 +1025,8 @@ static void apc_getcaps(int qco)
 
 	if (temp[0] != '#') {
 		upslogx(LOG_WARNING, "unknown capability start char [%c] !", temp[0]);
-		upsdebugx(1, "please report this caps string: %s", temp);
+		upsdebugx(1, "%s: please report this caps string: %s",
+			__func__, temp);
 		return;
 	}
 
@@ -1060,7 +1085,8 @@ static void apc_getcaps(int qco)
 
 		/* mark this as writable */
 		if (valid) {
-			upsdebugx(1, "%s [%s(%c)] - capability supported", vt->name, prtchr(cmd), loc);
+			upsdebugx(1, "%s: %s [%s(%c)] - capability supported",
+				__func__, vt->name, prtchr(cmd), loc);
 
 			dstate_setflags(vt->name, ST_FLAG_RW);
 
@@ -1118,7 +1144,7 @@ static void protocol_verify(unsigned char cmd)
 		return;
 
 	/*
-	 * loop necessary for apc:nut 1:n cases (e.g. T -> device.uptime,
+	 * loop necessary for APC:NUT 1:n cases (e.g. T -> device.uptime,
 	 * ambient.0.temperature)
 	 */
 	found = 0;
@@ -1134,7 +1160,7 @@ static void protocol_verify(unsigned char cmd)
 
 	/*
 	 * see if it's a command
-	 * loop necessary for apc:nut 1:n cases (e.g. D -> calibrate.start,
+	 * loop necessary for APC:NUT 1:n cases (e.g. D -> calibrate.start,
 	 * calibrate.stop)
 	 */
 	found = 0;
@@ -1162,7 +1188,7 @@ static void oldapcsetup(void)
 {
 	/*
 	 * note: battery.date and ups.id make little sense here, as
-	 * that would imply writability and this is an *old* apc psu
+	 * that would imply writability and this is an *old* APC UPS
 	 */
 	legacy_verify("ups.temperature");
 	legacy_verify("ups.load");
@@ -1183,26 +1209,27 @@ static void oldapcsetup(void)
 	if (vt_lookup_name("output.current"))
 		dstate_setinfo("ups.model", "Matrix-UPS");
 	else {
-		/* really old models don't support ups.model (apc: 0x01) */
+		/* really old models don't support ups.model (APC: 0x01) */
 		if (!vt_lookup_name("ups.model"))
 			/* force the model name */
 			dstate_setinfo("ups.model", "Smart-UPS");
 	}
 
 	/*
-	 * If we have come down this path then we dont do capabilities and
+	 * If we have come down this path then we don't do capabilities and
 	 * other shiny features.
 	 */
 }
 
-/* some hardware is a special case - hotwire the list of cmdchars */
+/* some hardware is a special case - hot-wire the list of cmdchars */
 static int firmware_table_lookup(void)
 {
 	ssize_t ret;
 	unsigned int i, j;
 	char buf[APC_LBUF];
 
-	upsdebugx(1, "attempting firmware lookup using [%s]", prtchr(APC_FW_OLD));
+	upsdebugx(1, "%s: attempting firmware lookup using [%s]",
+		__func__, prtchr(APC_FW_OLD));
 
 	apc_flush(0);
 	if (apc_write(APC_FW_OLD) != 1)
@@ -1215,7 +1242,8 @@ static int firmware_table_lookup(void)
 	 * firmware version, we attempt that only if 'V' doesn't work.
 	 */
 	if (!ret || !strcmp(buf, "NA")) {
-		upsdebugx(1, "attempting firmware lookup using [%s]", prtchr(APC_FW_NEW));
+		upsdebugx(1, "%s: attempting firmware lookup using [%s]",
+			__func__, prtchr(APC_FW_NEW));
 
 		if (apc_write(APC_FW_NEW) != 1)
 			return 0;
@@ -1223,12 +1251,12 @@ static int firmware_table_lookup(void)
 			return 0;
 	}
 
-	upsdebugx(1, "detected firmware version: %s", buf);
+	upsdebugx(1, "%s: detected firmware version: %s", __func__, buf);
 
 	/* this will be reworked if we get a lot of these things */
 	if (!strcmp(buf, "451.2.I")) {
 		/* quirk_capability_overflow */
-		upsdebugx(1, "WARN: quirky firmware !");
+		upsdebugx(1, "%s: WARN: quirky firmware !", __func__);
 		return 2;
 	}
 
@@ -1238,13 +1266,16 @@ static int firmware_table_lookup(void)
 		 * through 'b'; see:
 		 * http://article.gmane.org/gmane.comp.monitoring.nut.user/7762
 		 */
-		strcpy(buf, "set\1");
+		memset(buf, '\0', sizeof(buf));
+		strncpy(buf, "set\1", sizeof(buf) - 1);
+		buf[sizeof(buf) - 1] = '\0';
 	}
 
 	for (i = 0; apc_compattab[i].firmware != NULL; i++) {
 		if (!strcmp(apc_compattab[i].firmware, buf)) {
 
-			upsdebugx(1, "matched firmware: %s", apc_compattab[i].firmware);
+			upsdebugx(1, "%s: matched firmware: %s",
+				__func__, apc_compattab[i].firmware);
 
 			/* magic ? */
 			if (strspn(apc_compattab[i].firmware, "05")) {
@@ -1254,7 +1285,9 @@ static int firmware_table_lookup(void)
 			}
 
 			/* matched - run the cmdchars from the table */
-			upsdebugx(1, "parsing out supported cmds and vars");
+			upsdebugx(1,
+				"%s: parsing out supported cmds and vars",
+				__func__);
 			for (j = 0; j < strlen(apc_compattab[i].cmdchars); j++)
 				protocol_verify((const unsigned char)(apc_compattab[i].cmdchars[j]));
 			deprecate_vars();
@@ -1282,7 +1315,8 @@ static int getbaseinfo(void)
 		/* found compat */
 		return 1;
 
-	upsdebugx(1, "attempting var/cmdset lookup using [%s]", prtchr(APC_CMDSET));
+	upsdebugx(1, "%s: attempting var/cmdset lookup using [%s]",
+		__func__, prtchr(APC_CMDSET));
 	/*
 	 * Initially we ask the UPS what commands it takes. If this fails we are
 	 * going to need an alternate strategy - we can deal with that if it
@@ -1302,7 +1336,7 @@ static int getbaseinfo(void)
 		return 1;
 	}
 
-	upsdebugx(1, "parsing out supported cmds/vars");
+	upsdebugx(1, "%s: parsing out supported cmds/vars", __func__);
 	/*
 	 * returned set is verified for validity above, so just extract
 	 * what's interesting for us
@@ -1321,7 +1355,7 @@ static int getbaseinfo(void)
 
 	/* if capabilities are supported, add them here */
 	if (strchr(cmds, APC_CAPS)) {
-		upsdebugx(1, "parsing out caps");
+		upsdebugx(1, "%s: parsing out caps", __func__);
 		apc_getcaps(qco);
 	}
 	return 1;
@@ -1345,7 +1379,7 @@ static int do_cal(int start)
 
 	/* if we can't check the current calibration status, bail out */
 	if ((ret < 1) || (!strcmp(temp, "NA"))) {
-		upslogx(LOG_WARNING, "%s", "runtime calibration state undeterminable");
+		upslogx(LOG_WARNING, "%s", "runtime calibration state can not be determined");
 		return STAT_INSTCMD_HANDLED;		/* FUTURE: failure */
 	}
 
@@ -1429,7 +1463,7 @@ static int smartmode(void)
 /*
  * get the UPS talking to us in smart mode
  * note: this is weird overkill, but possibly excused due to some obscure
- * hardware/firmware combinations; simpler version commmented out above, for
+ * hardware/firmware combinations; simpler version commented out above, for
  * now let's keep minimally adjusted old one
  */
 static int smartmode(int cnt)
@@ -1444,7 +1478,7 @@ static int smartmode(int cnt)
 		if (apc_write(APC_GOSMART) != 1)
 			return 0;
 
-		/* timeout here is intented */
+		/* timeout here is intended */
 		ret = apc_read(temp, sizeof(temp), SER_TO|SER_D1);
 		if (ret > 0 && !strcmp(temp, "SM"))
 			return 1;	/* success */
@@ -1463,8 +1497,8 @@ static int smartmode(int cnt)
 }
 
 /*
- * all shutdown commands should respond with 'OK' or '*'
- * apc_read() handles conversion to 'OK' so we care only about that one
+ * all shutdown commands should respond with "OK" or "*"
+ * apc_read() handles conversion to "OK" so we care only about that one
  * ign allows for timeout without assuming an error
  */
 static int sdok(int ign)
@@ -1473,7 +1507,7 @@ static int sdok(int ign)
 	char temp[APC_SBUF];
 
 	/*
-	 * older upses on failed commands might just timeout, we cut down
+	 * older UPSes on failed commands might just timeout, we cut down
 	 * timeout grace though
 	 * furthermore, command 'Z' will not reply with anything
 	 */
@@ -1519,7 +1553,9 @@ static int sdcmd_CS(const void *foo)
 	if ((val = getval("cshdelay")))
 		cshd = (strtod(val, NULL) * 1000000);
 
-	upsdebugx(1, "%s: issuing CS 'hack' [%s+%s] with %2.1f sec delay", __func__, prtchr(APC_CMD_SIMPWF), prtchr(APC_CMD_SOFTDOWN), (double)cshd / 1000000);
+	upsdebugx(1, "%s: issuing CS 'hack' [%s+%s] with %2.1f sec delay",
+		__func__, prtchr(APC_CMD_SIMPWF), prtchr(APC_CMD_SOFTDOWN),
+		(double)cshd / 1000000);
 	if (ups_status & APC_STAT_OL) {
 		apc_flush(0);
 		upsdebugx(1, "%s: issuing [%s]", __func__, prtchr(APC_CMD_SIMPWF));
@@ -1550,6 +1586,8 @@ static int sdcmd_AT(const void *str)
 	const char *awd = str;
 	char temp[APC_SBUF], *ptr;
 
+	memset(temp, '\0', sizeof(temp));
+
 	if (!awd)
 		awd = "000";
 
@@ -1561,10 +1599,11 @@ static int sdcmd_AT(const void *str)
 	for (i = cnt; i < padto ; i++) {
 		*ptr++ = '0';
 	}
-	strcpy(ptr, awd);
+	strncpy(ptr, awd, sizeof(temp) - (ptr - temp) - 1);
+	temp[sizeof(temp) - 1] = '\0';
 
-	upsdebugx(1, "%s: issuing [%s] with %ld minutes of additional wakeup delay",
-			__func__, prtchr(APC_CMD_GRACEDOWN), strtol(awd, NULL, 10)*6);
+	upsdebugx(1, "%s: issuing [%s] with %ld minutes of additional wake-up delay",
+		__func__, prtchr(APC_CMD_GRACEDOWN), strtol(awd, NULL, 10)*6);
 
 	apc_flush(0);
 	ret = apc_write_long(temp);
@@ -1586,7 +1625,7 @@ static int sdcmd_AT(const void *str)
 	/*
 	 * "tricky" part - we tried @nn variation and it (unsurprisingly)
 	 * failed; we have to abort the sequence with something bogus to have
-	 * the clean state; newer upses will respond with 'NO', older will be
+	 * the clean state; newer UPSes will respond with "NO", older will be
 	 * silent (YMMV);
 	 */
 	apc_write(APC_GOSMART);
@@ -1626,7 +1665,7 @@ static int sdcmd_Z(const void *foo)
 		return STAT_INSTCMD_FAILED;
 	}
 
-	/* note: ups will not reply anything after this command */
+	/* note: UPS will not reply anything after this command */
 	return sdok(1);
 }
 
@@ -1777,7 +1816,7 @@ static int setvar_enum(apc_vartab_t *vt, const char *val)
 
 	ptr = convert_data(vt, orig);
 
-	/* suppress redundant changes - easier on the eeprom */
+	/* suppress redundant changes - easier on the EEPROM */
 	if (!strcmp(ptr, val)) {
 		upslogx(LOG_INFO, "%s: ignoring SET %s='%s' (unchanged value)",
 			__func__, vt->name, val);
@@ -1851,6 +1890,8 @@ static int setvar_string(apc_vartab_t *vt, const char *val)
 		return STAT_SET_FAILED;
 	}
 
+	memset(temp, '\0', sizeof(temp));
+
 	apc_flush(SER_AA);
 	if (apc_write((const unsigned char)vt->cmd) != 1)
 		return STAT_SET_FAILED;
@@ -1860,7 +1901,7 @@ static int setvar_string(apc_vartab_t *vt, const char *val)
 	if ((ret < 1) || (!strcmp(temp, "NA")))
 		return STAT_SET_FAILED;
 
-	/* suppress redundant changes - easier on the eeprom */
+	/* suppress redundant changes - easier on the EEPROM */
 	if (!strcmp(temp, val)) {
 		upslogx(LOG_INFO, "%s: ignoring SET %s='%s' (unchanged value)",
 			__func__, vt->name, val);
@@ -1870,7 +1911,8 @@ static int setvar_string(apc_vartab_t *vt, const char *val)
 
 	/* length sanitized above */
 	temp[0] = APC_NEXTVAL;
-	strcpy(temp + 1, val);
+	strncpy(temp + 1, val, sizeof(temp) - 1);
+	temp[sizeof(temp) - 1] = '\0';
 	ptr = temp + strlen(temp);
 	for (i = strlen(val); i < APC_STRLEN; i++)
 		*ptr++ = '\015'; /* pad with CRs */
@@ -1933,7 +1975,7 @@ static int do_loadon(void)
 		return STAT_INSTCMD_FAILED;
 
 	/*
-	 * ups will not reply anything after this command, but might
+	 * UPS will not reply anything after this command, but might
 	 * generate brief OVER condition (which will be corrected on
 	 * the next status update)
 	 */
@@ -1942,7 +1984,7 @@ static int do_loadon(void)
 	return STAT_INSTCMD_HANDLED;
 }
 
-/* actually send the instcmd's char to the ups */
+/* actually send the instcmd's char to the UPS */
 static int do_cmd(const apc_cmdtab_t *ct)
 {
 	ssize_t ret;
@@ -2085,7 +2127,7 @@ void upsdrv_makevartable(void)
 {
 	addvar(VAR_VALUE, "ttymode", "tty discipline selection");
 	addvar(VAR_VALUE, "cable", "alternate cable (940-0095B) selection");
-	addvar(VAR_VALUE, "awd", "hard hibernate's additional wakeup delay");
+	addvar(VAR_VALUE, "awd", "hard hibernate's additional wake-up delay");
 	addvar(VAR_VALUE, "sdtype", "simple shutdown method");
 	addvar(VAR_VALUE, "advorder", "advanced shutdown control");
 	addvar(VAR_VALUE, "cshdelay", "CS hack delay");
@@ -2105,7 +2147,7 @@ void upsdrv_initups(void)
 	char *val;
 	apc_vartab_t *ptr;
 
-	/* sanitize awd (additional waekup delay of '@' command) */
+	/* sanitize awd (additional wake-up delay of '@' command) */
 	if ((val = getval("awd")) && !rexhlp(APC_AWDFMT, val)) {
 			fatalx(EXIT_FAILURE, "invalid value (%s) for option 'awd'", val);
 	}
@@ -2164,7 +2206,7 @@ void upsdrv_initinfo(void)
 			);
 	}
 
-	/* manufacturer ID - hardcoded in this particular module */
+	/* manufacturer ID - hard-coded in this particular module */
 	dstate_setinfo("ups.mfr", "APC");
 
 	if (!(pmod = dstate_getinfo("ups.model")))
@@ -2172,7 +2214,8 @@ void upsdrv_initinfo(void)
 	if (!(pser = dstate_getinfo("ups.serial")))
 		pser = "unknown serial";
 
-	upsdebugx(1, "detected %s [%s] on %s", pmod, pser, device_path);
+	upsdebugx(1, "%s: detected %s [%s] on %s",
+		__func__, pmod, pser, device_path);
 
 	setuphandlers();
 	/*
@@ -2189,22 +2232,70 @@ void upsdrv_updateinfo(void)
 	int all;
 	time_t now;
 
-	/* try to wake up a dead ups once in awhile */
+	/* try to wake up a dead UPS once in awhile */
 	if (dstate_is_stale()) {
+		char temp[LARGEBUF];
+		size_t count = 0;
+
 		if (!last_worked)
 			upsdebugx(1, "%s: %s", __func__, "comm lost");
 
 		/* reset this so a full update runs when the UPS returns */
 		last_full = 0;
 
+		/* Flush the buffer in case it helps,
+		 * or sleep 1 sec if buffer is empty */
+		while (select_read(upsfd, temp, sizeof(temp), 1, 0) > 0) {
+			count++;
+		}
+		errno = 0;
+
+		if (!count) {
+			/* Do not flood the device (and our logs, below)
+			 * with retry attempts */
+			usleep(1000000);
+		}
+
 		if (++last_worked < 10)
 			return;
 
 		/* become aggressive after a few tries */
-		upsdebugx(1, "%s: nudging ups with 'Y', iteration #%d ...", __func__, last_worked);
-		if (!smartmode(1))
+		if (!(last_worked % 60)) {
+			upslogx(LOG_WARNING, "Trying to reconnect to the UPS");
+			dstate_setinfo("driver.state", "reconnect.trying");
+
+			upsdebugx(1, "%s: call upsdrv_cleanup", __func__);
+			/* dstate_setinfo("driver.state", "cleanup.upsdrv"); */
+			upsdrv_cleanup();
+
+			upsdebugx(1, "%s: sleep 5 sec", __func__);
+			usleep(5000000);
+
+			upsdebugx(1, "%s: call upsdrv_initups", __func__);
+			/* dstate_setinfo("driver.state", "init.device"); */
+			upsdrv_initups();
+
+			upsdebugx(1, "%s: call upsdrv_initinfo", __func__);
+			/* dstate_setinfo("driver.state", "init.info"); */
+			upsdrv_initinfo();
+
+			upsdebugx(1, "%s: call upsdrv_updateinfo", __func__);
+			dstate_setinfo("driver.state", "reconnect.updateinfo");
+			/* dstate_setinfo("driver.state", "init.updateinfo"); */
+			upsdrv_updateinfo();
+
+			dstate_setinfo("driver.state", "init.quiet");
+		}
+
+		upsdebugx(1, "%s: nudging UPS with 'Y', iteration #%d ...",
+			__func__, last_worked);
+		if (!smartmode(1)) {
 			return;
+		}
 
+		if (last_worked > 10)
+			upslogx(LOG_WARNING, "%s: recovered the connection", __func__);
+		upsdebugx(1, "%s: recovered the connection", __func__);
 		last_worked = 0;
 	}
 
diff --git a/drivers/apcupsd-ups.c b/drivers/apcupsd-ups.c
index 82bc3af631..9f4b71bc20 100644
--- a/drivers/apcupsd-ups.c
+++ b/drivers/apcupsd-ups.c
@@ -57,7 +57,7 @@ typedef struct pollfd {
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"apcupsd network client UPS driver"
-#define DRIVER_VERSION	"0.71"
+#define DRIVER_VERSION	"0.72"
 
 #define POLL_INTERVAL_MIN 10
 
diff --git a/drivers/arduino-hid.c b/drivers/arduino-hid.c
index 59206cbfd0..c63fff7573 100644
--- a/drivers/arduino-hid.c
+++ b/drivers/arduino-hid.c
@@ -151,18 +151,24 @@ static int arduino_claim(HIDDevice_t *hd)
 		case POSSIBLY_SUPPORTED:
 			/* by default, reject, unless the productid option is given */
 			if (getval("productid")) {
-				usb->hid_ep_in=4;
-				usb->hid_ep_out=5;
-				usb->hid_rep_index = 2;
+				if (!getval("usb_hid_ep_in"))
+					usb->hid_ep_in=4;
+				if (!getval("usb_hid_ep_out"))
+					usb->hid_ep_out=5;
+				if (!getval("usb_hid_rep_index"))
+					usb->hid_rep_index = 2;
 				return 1;
 			}
 			possibly_supported("Arduino", hd);
 			return 0;
 
 		case SUPPORTED:
-			usb->hid_ep_in=4;
-			usb->hid_ep_out=5;
-			usb->hid_rep_index = 2;
+			if (!getval("usb_hid_ep_in"))
+				usb->hid_ep_in=4;
+			if (!getval("usb_hid_ep_out"))
+				usb->hid_ep_out=5;
+			if (!getval("usb_hid_rep_index"))
+				usb->hid_rep_index = 2;
 			return 1;
 
 		case NOT_SUPPORTED:
diff --git a/drivers/asem.c b/drivers/asem.c
index d35a54746a..82b4746627 100644
--- a/drivers/asem.c
+++ b/drivers/asem.c
@@ -67,7 +67,7 @@
 #endif
 
 #define DRIVER_NAME	"ASEM"
-#define DRIVER_VERSION	"0.12"
+#define DRIVER_VERSION	"0.13"
 
 /* Valid on ASEM PB1300 UPS */
 #define BQ2060_ADDRESS	0x0B
diff --git a/drivers/bcmxcp.c b/drivers/bcmxcp.c
index fd6676ff9a..63822ae876 100644
--- a/drivers/bcmxcp.c
+++ b/drivers/bcmxcp.c
@@ -110,15 +110,13 @@ TODO List:
 
 
 #include "main.h"
-#include <math.h>       /* For ldexp() */
-#include <float.h>      /*for FLT_MAX */
-
-#include "nut_stdint.h" /* for uint8_t, uint16_t, uint32_t, ... */
+#include "nut_float.h"	/* For ldexp(), FLT_MAX */
+#include "nut_stdint.h"	/* for uint8_t, uint16_t, uint32_t, ... */
 #include "bcmxcp_io.h"
 #include "bcmxcp.h"
 
-#define DRIVER_NAME    "BCMXCP UPS driver"
-#define DRIVER_VERSION "0.33"
+#define DRIVER_NAME	"BCMXCP UPS driver"
+#define DRIVER_VERSION	"0.35"
 
 #define MAX_NUT_NAME_LENGTH 128
 #define NUT_OUTLET_POSITION   7
@@ -1160,6 +1158,8 @@ void init_ext_vars(void)
 						dstate_setaux("battery.packs", 1);
 						break;
 
+			default:
+						break;
 		}
 	}
 }
@@ -2098,6 +2098,8 @@ static int instcmd(const char *cmdname, const char *extra)
 				cbuf[2] = 0x2;
 				break;                  /*mute beeper*/
 				}
+			default:
+				break;
 		}
 		cbuf[3] = 0x0;          /*padding*/
 
@@ -2216,6 +2218,10 @@ void upsdrv_help(void)
 /* list flags and values that you want to receive via -x */
 void upsdrv_makevartable(void)
 {
+	/* NOTE: The USB variant of this driver currently does not
+	 * involve nut_usb_addvars() method like others do. When
+	 * fixing, see also tools/nut-scanner/scan_usb.c "exceptions".
+	 */
 	addvar(VAR_VALUE, "shutdown_delay", "Specify shutdown delay (seconds)");
 	addvar(VAR_VALUE, "baud_rate", "Specify communication speed (ex: 9600)");
 }
diff --git a/drivers/belkin-hid.c b/drivers/belkin-hid.c
index 686dc92612..c096282d3a 100644
--- a/drivers/belkin-hid.c
+++ b/drivers/belkin-hid.c
@@ -3,7 +3,9 @@
  *  Copyright (C)
  *  2003 - 2008 Arnaud Quette <arnaud.quette@free.fr>
  *  2005        Peter Selinger <selinger@users.sourceforge.net>
- *  2011, 2014  Charles Lepple <clepple+nut@gmail>
+ *  2011, 2014  Charles Lepple <clepple+nut@gmail.com>
+ *  2024        James R. Parks <jrjparks@zathera.com>
+ *  2024        Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  Sponsored by MGE UPS SYSTEMS <http://www.mgeups.com>
  *
@@ -24,14 +26,13 @@
  *
  */
 
-#include "main.h"     /* for getval() */
+#include "main.h"	/* for getval() */
 #include "usbhid-ups.h"
 #include "belkin-hid.h"
 #include "usb-common.h"
+#include "nut_float.h"	/* For fabs() */
 
-#include <math.h>     /* for fabs() */
-
-#define BELKIN_HID_VERSION      "Belkin/Liebert HID 0.18"
+#define BELKIN_HID_VERSION	"Belkin/Liebert HID 0.22"
 
 /* Belkin */
 #define BELKIN_VENDORID	0x050d
@@ -68,9 +69,11 @@ static usb_device_id_t belkin_usb_device_table[] = {
 	{ USB_DEVICE(BELKIN_VENDORID, 0x1100), NULL },
 
 	/* Liebert GXT4 UPS */
-	{ USB_DEVICE(LIEBERT_VENDORID, 0x0004), NULL },
+	{ USB_DEVICE(LIEBERT_VENDORID, 0x0000), NULL },
 	/* Liebert PowerSure PSA UPS */
 	{ USB_DEVICE(LIEBERT_VENDORID, 0x0001), NULL },
+	/* Liebert PowerSure PST UPS */
+	{ USB_DEVICE(LIEBERT_VENDORID, 0x0002), NULL },
 	/* Liebert PowerSure PSI 1440 */
 	{ USB_DEVICE(LIEBERT_VENDORID, 0x0004), NULL },
 	/* Liebert GXT3 */
@@ -86,31 +89,39 @@ static const char *liebert_charging_fun(double value);
 static const char *liebert_lowbatt_fun(double value);
 static const char *liebert_replacebatt_fun(double value);
 static const char *liebert_shutdownimm_fun(double value);
+
+/* These lookup functions also cover the 1e-7 factor which seems to
+ * be due to a broken report descriptor in certain Liebert units.
+ * Exposed for unit testing - not "static" */
 static const char *liebert_config_voltage_fun(double value);
 static const char *liebert_line_voltage_fun(double value);
 
+static double liebert_config_voltage_mult = 1.0;
+static double liebert_line_voltage_mult = 1.0;
+static char liebert_conversion_buf[10];
+
 static info_lkp_t liebert_online_info[] = {
 	{ 0, NULL, liebert_online_fun, NULL }
 };
 
 static info_lkp_t liebert_discharging_info[] = {
-        { 0, NULL, liebert_discharging_fun, NULL }
+	{ 0, NULL, liebert_discharging_fun, NULL }
 };
 
 static info_lkp_t liebert_charging_info[] = {
-        { 0, NULL, liebert_charging_fun, NULL }
+	{ 0, NULL, liebert_charging_fun, NULL }
 };
 
 static info_lkp_t liebert_lowbatt_info[] = {
-        { 0, NULL, liebert_lowbatt_fun, NULL }
+	{ 0, NULL, liebert_lowbatt_fun, NULL }
 };
 
 static info_lkp_t liebert_replacebatt_info[] = {
-        { 0, NULL, liebert_replacebatt_fun, NULL }
+	{ 0, NULL, liebert_replacebatt_fun, NULL }
 };
 
 static info_lkp_t liebert_shutdownimm_info[] = {
-        { 0, NULL, liebert_shutdownimm_fun, NULL }
+	{ 0, NULL, liebert_shutdownimm_fun, NULL }
 };
 
 static info_lkp_t liebert_config_voltage_info[] = {
@@ -121,13 +132,6 @@ static info_lkp_t liebert_line_voltage_info[] = {
 	{ 0, NULL, liebert_line_voltage_fun, NULL },
 };
 
-static double liebert_config_voltage_mult = 1.0;
-static double liebert_line_voltage_mult = 1.0;
-static char liebert_conversion_buf[10];
-
-/* These lookup functions also cover the 1e-7 factor which seems to be due to a
- * broken report descriptor in certain Liebert units.
- */
 static const char *liebert_online_fun(double value)
 {
 	return value ? "online" : "!online";
@@ -164,8 +168,13 @@ static const char *liebert_shutdownimm_fun(double value)
  */
 static const char *liebert_config_voltage_fun(double value)
 {
-	if( value < 1 ) {
-		if( fabs(value - 1e-7) < 1e-9 ) {
+	/* Does not fire with devices seen diring investigation for
+	 *   https://github.com/networkupstools/nut/issues/2370
+	 * as the ones seen serve nominal "config" values as integers
+	 * (e.g. "230" for line and "24" for battery).
+	 */
+	if (value < 1) {
+		if (fabs(value - 1e-7) < 1e-9) {
 			liebert_config_voltage_mult = 1e8;
 			liebert_line_voltage_mult = 1e7; /* stomp this in case input voltage was low */
 			upsdebugx(2, "ConfigVoltage = %g -> assuming correction factor = %g",
@@ -182,9 +191,33 @@ static const char *liebert_config_voltage_fun(double value)
 
 static const char *liebert_line_voltage_fun(double value)
 {
-	if( value < 1 ) {
-		if( fabs(value - 1e-7) < 1e-9 ) {
+	/* Keep large readings like "230" or "24" as is */
+	if (value < 1) {
+		int picked_scale = 0;
+		/* NOTE: Start with tiniest scale first */
+
+		/* Practical use-case for mult=1e7:
+		 *   1.39e-06  =>  13.9
+		 *   2.201e-05 => 220.1
+		 * NOTE: The clause below is in fact broken for this use-case,
+		 * but was present in sources for ages (worked wrongly with an
+		 * integer-oriented abs() so collapsed into "if (0 < 1e-9) {")!
+		 *   if (fabs(value - 1e-7) < 1e-9) {
+		 */
+		if (fabs(value - 1e-5) < 4*1e-5) {
 			liebert_line_voltage_mult = 1e7;
+			picked_scale = 1;
+		} else
+		/* Practical use-case for mult=1e5:
+		 *   0.000273 =>  27.3
+		 *   0.001212 => 121.2
+		 */
+		if (fabs(value - 1e-3) < 4*1e-3) {
+			liebert_line_voltage_mult = 1e5;
+			picked_scale = 1;
+		}
+
+		if (picked_scale) {
 			upsdebugx(2, "Input/OutputVoltage = %g -> assuming correction factor = %g",
 				value, liebert_line_voltage_mult);
 		} else {
@@ -480,6 +513,17 @@ static hid_info_t belkin_hid2nut[] = {
   { "battery.voltage", 0, 0, "UPS.PowerSummary.Voltage", NULL, "%s", 0, liebert_line_voltage_info },
   { "battery.voltage.nominal", 0, 0, "UPS.PowerSummary.ConfigVoltage", NULL, "%s", HU_FLAG_STATIC, liebert_config_voltage_info },
   { "ups.load", 0, 0, "UPS.Output.PercentLoad", NULL, "%.0f", 0, NULL },
+  /* Liebert PSI5 */
+  { "input.voltage.nominal", 0, 0, "UPS.Flow.ConfigVoltage", NULL, "%.0f", 0, NULL },
+  { "input.frequency", 0, 0, "UPS.PowerConverter.Input.Frequency", NULL, "%s", 0, divide_by_100_conversion },
+  { "input.voltage", 0, 0, "UPS.PowerConverter.Input.Voltage", NULL, "%s", 0, liebert_line_voltage_info },
+  { "output.voltage.nominal", 0, 0, "UPS.Flow.ConfigVoltage", NULL, "%.0f", 0, NULL },
+  { "output.frequency", 0, 0, "UPS.PowerConverter.Output.Frequency", NULL, "%s", 0, divide_by_100_conversion },
+  { "output.voltage", 0, 0, "UPS.PowerConverter.Output.Voltage", NULL, "%s", 0, liebert_line_voltage_info },
+  { "ups.load", 0, 0, "UPS.OutletSystem.Outlet.PercentLoad", NULL, "%.0f", 0, NULL },
+  { "battery.voltage", 0, 0, "UPS.BatterySystem.Battery.Voltage", NULL, "%s", 0, liebert_line_voltage_info },
+  { "battery.voltage.nominal", 0, 0, "UPS.BatterySystem.Battery.ConfigVoltage", NULL, "%.0f", 0, NULL },
+  { "battery.capacity", 0, 0, "UPS.Flow.ConfigApparentPower", NULL, "%.0f", 0, NULL },
   /* status */
   { "BOOL", 0, 0, "UPS.PowerSummary.Discharging", NULL, NULL, HU_FLAG_QUICK_POLL, liebert_discharging_info }, /* might not need to be liebert_* version */
   { "BOOL", 0, 0, "UPS.PowerSummary.Charging", NULL, NULL, HU_FLAG_QUICK_POLL, liebert_charging_info },
@@ -621,6 +665,9 @@ static int belkin_claim(HIDDevice_t *hd)
 			}
 			possibly_supported("Liebert", hd);
 			return 0;
+
+		default:
+			break;
 		}
 		return 0;
 
diff --git a/drivers/belkin.c b/drivers/belkin.c
index 34a3f39b24..8b339d2260 100644
--- a/drivers/belkin.c
+++ b/drivers/belkin.c
@@ -29,7 +29,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Belkin Smart protocol driver"
-#define DRIVER_VERSION	"0.26"
+#define DRIVER_VERSION	"0.27"
 
 static ssize_t init_communication(void);
 static ssize_t get_belkin_reply(char *buf);
diff --git a/drivers/belkinunv.c b/drivers/belkinunv.c
index 83826a8b7f..0c82865321 100644
--- a/drivers/belkinunv.c
+++ b/drivers/belkinunv.c
@@ -94,7 +94,7 @@
 #include "serial.h"
 
 #define DRIVER_NAME	"Belkin 'Universal UPS' driver"
-#define DRIVER_VERSION	"0.09"
+#define DRIVER_VERSION	"0.10"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/bestfcom.c b/drivers/bestfcom.c
index 38a996dac1..5402114652 100644
--- a/drivers/bestfcom.c
+++ b/drivers/bestfcom.c
@@ -45,7 +45,7 @@
 #include "serial.h"
 
 #define DRIVER_NAME	"Best Ferrups/Fortress driver"
-#define DRIVER_VERSION	"0.14"
+#define DRIVER_VERSION	"0.15"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/bestfortress.c b/drivers/bestfortress.c
index d86d1b4daa..8c650abb60 100644
--- a/drivers/bestfortress.c
+++ b/drivers/bestfortress.c
@@ -35,7 +35,7 @@
 #endif
 
 #define DRIVER_NAME     "Best Fortress UPS driver"
-#define DRIVER_VERSION  "0.08"
+#define DRIVER_VERSION  "0.09"
 
 /* driver description structure */
 upsdrv_info_t   upsdrv_info = {
diff --git a/drivers/bestuferrups.c b/drivers/bestuferrups.c
index c248b13ba7..1585d6a903 100644
--- a/drivers/bestuferrups.c
+++ b/drivers/bestuferrups.c
@@ -33,7 +33,7 @@
 #include "serial.h"
 
 #define DRIVER_NAME	"Best Ferrups Series ME/RE/MD driver"
-#define DRIVER_VERSION	"0.05"
+#define DRIVER_VERSION	"0.06"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/bestups.c b/drivers/bestups.c
index d388658e12..b34e804c5b 100644
--- a/drivers/bestups.c
+++ b/drivers/bestups.c
@@ -29,7 +29,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Best UPS driver"
-#define DRIVER_VERSION	"1.08"
+#define DRIVER_VERSION	"1.09"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -209,6 +209,9 @@ static void ups_ident(void)
 		case 5:
 			highvolt = atof(ptr);
 			break;
+
+		default:
+			break;
 		}
 
 		ptr = strtok(NULL, ",");
diff --git a/drivers/bicker_ser.c b/drivers/bicker_ser.c
new file mode 100644
index 0000000000..a5c2c4db49
--- /dev/null
+++ b/drivers/bicker_ser.c
@@ -0,0 +1,925 @@
+/*
+ * bicker_ser.c: support for Bicker SuperCapacitors DC UPSes
+ *
+ * Copyright (C) 2024 - Nicola Fontana <ntd@entidi.it>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/* The protocol is reported in many Bicker's manuals but (according to
+ * Bicker itself) the best source is the UPS Gen Software's user manual:
+ *
+ * https://www.bicker.de/media/pdf/ff/cc/fe/en_user_manual_ups-gen2-configuration-software.pdf
+ *
+ * Basically, this is a binary protocol without checksums:
+ *
+ *  1 byte  1 byte  1 byte  1 byte  0..252 bytes  1 byte
+ * +-------+-------+-------+-------+--- - - - ---+-------+
+ * |  SOH  | Size  | Index |  CMD  |    Data     |  EOT  |
+ * +-------+-------+-------+-------+--- - - - ---+-------+
+ *         |        HEADER         |
+ *
+ * where:
+ * - `SOH` is the start signal (0x01)
+ * - `Size` is the length (in bytes) of the header and the data field
+ * - `Index` is the command index: see AVAILABLE COMMANDS
+ * - `CMD` is the command code to execute: see AVAILABLE COMMANDS
+ * - `Data` is the (optional) argument of the command
+ * - `EOT` is the end signal (0x04)
+ *
+ * The same format is used for incoming and outcoming packets. The data
+ * returned in the `Data` field is always in little-endian order.
+ *
+ * AVAILABLE COMMANDS
+ * ------------------
+ *
+ * - Index = 0x01 (GENERIC)
+ *   - CMD = 0x40 (status flags)
+ *   - CMD = 0x41 (input voltage)
+ *   - CMD = 0x42 (input current)
+ *   - CMD = 0x43 (output voltage)
+ *   - CMD = 0x44 (output current)
+ *   - CMD = 0x45 (battery voltage)
+ *   - CMD = 0x46 (battery current)
+ *   - CMD = 0x47 (battery state of charge)
+ *   - CMD = 0x48 (battery state of health)
+ *   - CMD = 0x49 (battery cycles)
+ *   - CMD = 0x4A (battery temperature)
+ *   - CMD = 0x60 (manufacturer)
+ *   - CMD = 0x61 (serial number)
+ *   - CMD = 0x62 (device name)
+ *   - CMD = 0x63 (firmware version)
+ *   - CMD = 0x64 (battery pack)
+ *   - CMD = 0x65 (firmware core version)
+ *   - CMD = 0x66 (CPU temperature)
+ *   - CMD = 0x67 (hardware revision)
+ *   - CMD = 0x21 (UPS output)
+ *   - CMD = 0x2F (shutdown flag)
+ *   - CMD = 0x7A (reset parameter settings)
+ *
+ * - Index = 0x07 (PARAMETER)
+ *   - CMD = 0x00 (get/set dummy entry: do not use!)
+ *   - CMD = 0x01 (get/set load sensor)
+ *   - CMD = 0x02 (get/set maximum backup time)
+ *   - CMD = 0x03 (get/set os shutdown by timer)
+ *   - CMD = 0x04 (get/set restart delay timer)
+ *   - CMD = 0x05 (get/set minimum capacity to start)
+ *   - CMD = 0x06 (get/set maximum backup time by in-1)
+ *   - CMD = 0x07 (get/set os shutdown by soc)
+ *   - CMD = 0x08 (get/set battery soc low threshold)
+ *   - CMD = 0x09 (get/set relay event configuration)
+ *   - CMD = 0x0A (get/set RS232 port configuration: place holder!)
+ *
+ * - Index = 0x03 (COMMANDS GOT FROM UPSIC MANUAL)
+ *   - CMD = 0x1B (GetChargeStatusRegister)
+ *   - CMD = 0x1C (GetMonitorStatusRegister)
+ *   - CMD = 0x1E (GetCapacity)
+ *   - CMD = 0x1F (GetEsr)
+ *   - CMD = 0x20 (GetVCap1Voltage)
+ *   - CMD = 0x21 (GetVCap2Voltage)
+ *   - CMD = 0x22 (GetVCap3Voltage)
+ *   - CMD = 0x23 (GetVCap4Voltage)
+ *   - CMD = 0x25 (GetInputVoltage)
+ *   - CMD = 0x26 (GetCapStackVoltage)
+ *   - CMD = 0x27 (GetOutputVoltage)
+ *   - CMD = 0x28 (GetInputCurrent)
+ *   - CMD = 0x29 (GetChargeCurrent)
+ *   - CMD = 0x31 (StartCapEsrMeasurement)
+ *   - CMD = 0x32 (SetTimeToShutdown)
+ */
+
+#include "config.h"
+#include "main.h"
+#include "attribute.h"
+#include "nut_stdint.h"
+
+#include "serial.h"
+
+#define DRIVER_NAME	"Bicker serial protocol"
+#define DRIVER_VERSION	"0.02"
+
+#define BICKER_SOH	0x01
+#define BICKER_EOT	0x04
+#define BICKER_TIMEOUT	1
+#define BICKER_DELAY	20
+#define BICKER_RETRIES	3
+#define BICKER_MAXID	0x0A /* Max parameter ID */
+#define BICKER_MAXVAL	0xFFFF /* Max parameter value */
+
+/* Protocol lengths */
+#define BICKER_HEADER		3
+#define BICKER_MAXDATA		(255 - BICKER_HEADER)
+#define BICKER_PACKET(datalen)	(1 + BICKER_HEADER + (datalen) + 1)
+
+#define TOUINT(ch)	((unsigned)(uint8_t)(ch))
+#define LOWBYTE(w)	((uint8_t)((uint16_t)(w) & 0x00FF))
+#define HIGHBYTE(w)	((uint8_t)(((uint16_t)(w) & 0xFF00) >> 8))
+#define WORDLH(l,h)	((uint16_t)((l) + ((h) << 8)))
+
+upsdrv_info_t upsdrv_info = {
+	DRIVER_NAME,
+	DRIVER_VERSION,
+	"Nicola Fontana <ntd@entidi.it>",
+	DRV_EXPERIMENTAL,
+	{ NULL }
+};
+
+typedef struct {
+	uint8_t  id;
+	uint16_t min;
+	uint16_t max;
+	uint16_t std;
+	uint8_t  enabled;
+	uint16_t value;
+} BickerParameter;
+
+typedef struct {
+	uint8_t     bicker_id;
+	const char *nut_name;
+	const char *description;
+} BickerMapping;
+
+static const BickerMapping bicker_mappings[] = {
+	/* Official variables present in docs/nut-names.txt */
+	{ 0x02, "ups.delay.shutdown",
+		"Interval to wait after shutdown with delay command (seconds)" },
+	{ 0x04, "ups.delay.start",
+		"Interval to wait before restarting the load (seconds)" },
+	{ 0x05, "battery.charge.restart",
+		"Minimum battery level for UPS restart after power-off" },
+	{ 0x07, "battery.charge.low",
+		"Remaining battery level when UPS switches to LB (percent)" },
+
+	/* Unofficial variables under the "experimental" namespace */
+	{ 0x01, "experimental.output.current.low",
+		"Current threshold under which the power will be cut (mA)" },
+	{ 0x03, "experimental.ups.delay.shutdown.signal",
+		"Interval to wait before sending the shutdown signal (seconds)" },
+	{ 0x06, "experimental.ups.delay.shutdown.signal.masked",
+		"Interval to wait with IN1 high before sending the shutdown signal (seconds)" },
+	{ 0x08, "experimental.battery.charge.low.empty",
+		"Battery level threshold for the empty signal (percent)" },
+	{ 0x09, "experimental.ups.relay.mode",
+		"Behavior of the relay" },
+};
+
+/**
+ * Parameter id validation.
+ * @param id      Id of the parameter
+ * @param context Description of the calling code for the log message
+ * @return 1 on valid id, 0 on errors.
+ *
+ * The id is valid if within the 0x01..BICKER_MAXID range (inclusive).
+ */
+static int bicker_valid_id(uint8_t id, const char *context)
+{
+	if (id < 1 || id > BICKER_MAXID) {
+		upslogx(LOG_ERR, "%s: parameter id 0x%02X is out of range (0x01..0x%02X)",
+			context, (unsigned)id, (unsigned)BICKER_MAXID);
+		return 0;
+	}
+	return 1;
+}
+
+/**
+ * Send a packet.
+ * @param idx     Command index
+ * @param cmd     Command
+ * @param data    Source data or NULL for no data field
+ * @param datalen Size of the source data field or 0
+ * @return        `datalen` on success or -1 on errors.
+ */
+static ssize_t bicker_send(uint8_t idx, uint8_t cmd, const void *data, size_t datalen)
+{
+	uint8_t buf[BICKER_PACKET(BICKER_MAXDATA)];
+	size_t buflen;
+	ssize_t ret;
+
+	if (data != NULL) {
+		if (datalen > BICKER_MAXDATA) {
+			upslogx(LOG_ERR,
+				"Data size exceeded: %" PRIuSIZE " > %d",
+				datalen, BICKER_MAXDATA);
+			return -1;
+		}
+		memcpy(&buf[1 + BICKER_HEADER], data, datalen);
+	} else {
+		datalen = 0;
+	}
+
+	ser_flush_io(upsfd);
+
+	buflen = BICKER_PACKET(datalen);
+	buf[0] = BICKER_SOH;
+	buf[1] = BICKER_HEADER + datalen;
+	buf[2] = idx;
+	buf[3] = cmd;
+	buf[buflen - 1] = BICKER_EOT;
+
+	ret = ser_send_buf(upsfd, buf, buflen);
+	if (ret < 0) {
+		upslog_with_errno(LOG_WARNING, "ser_send_buf failed");
+		return -1;
+	} else if ((size_t) ret != buflen) {
+		upslogx(LOG_WARNING, "ser_send_buf returned %"
+			PRIiSIZE " instead of %" PRIuSIZE,
+			ret, buflen);
+		return -1;
+	}
+
+	upsdebug_hex(3, "bicker_send", buf, buflen);
+	return datalen;
+}
+
+/**
+ * Receive a packet with a data field of unknown size.
+ * @param idx  Command index
+ * @param cmd  Command
+ * @param data Destination buffer or NULL to discard the data field
+ * @return     The size of the data field on success or -1 on errors.
+ *
+ * The data field is stored directly in the destination buffer. `data`,
+ * if not NULL, must have at least BICKER_MAXDATA bytes.
+ */
+static ssize_t bicker_receive(uint8_t idx, uint8_t cmd, void *data)
+{
+	ssize_t ret;
+	size_t buflen, datalen;
+	uint8_t buf[BICKER_PACKET(BICKER_MAXDATA)];
+
+	/* Read first two bytes (SOH + size) */
+	ret = ser_get_buf_len(upsfd, buf, 2, BICKER_TIMEOUT, 0);
+	if (ret < 0) {
+		upslog_with_errno(LOG_WARNING, "Initial ser_get_buf_len failed");
+		return -1;
+	} else if (ret < 2) {
+		upslogx(LOG_WARNING, "Timeout waiting for response packet");
+		return -1;
+	} else if (buf[0] != BICKER_SOH) {
+		upslogx(LOG_WARNING, "Received 0x%02X instead of SOH (0x%02X)",
+			(unsigned)buf[0], (unsigned)BICKER_SOH);
+		return -1;
+	}
+
+	/* buf[1] (the size field) is BICKER_HEADER + data length, so */
+	datalen = buf[1] - BICKER_HEADER;
+
+	/* Read the rest of the packet */
+	buflen = BICKER_PACKET(datalen);
+	ret = ser_get_buf_len(upsfd, buf + 2, buflen - 2, BICKER_TIMEOUT, 0);
+	if (ret < 0) {
+		upslog_with_errno(LOG_WARNING, "ser_get_buf_len failed");
+		return -1;
+	}
+
+	upsdebug_hex(3, "bicker_receive", buf, ret + 2);
+
+	if ((size_t)ret < buflen - 2) {
+		upslogx(LOG_WARNING, "Timeout waiting for the end of the packet");
+		return -1;
+	} else if (buf[buflen - 1] != BICKER_EOT) {
+		upslogx(LOG_WARNING, "Received 0x%02X instead of EOT (0x%02X)",
+			(unsigned)buf[buflen - 1], (unsigned)BICKER_EOT);
+		return -1;
+	} else if (idx != 0xEE && buf[2] == 0xEE) {
+		/* I found experimentally that, when the syntax is
+		 * formally correct but a feature is not supported,
+		 * the device returns 0x01 0x03 0xEE 0x07 0x04. */
+		upsdebugx(2, "Command is not supported");
+		return -1;
+	} else if (buf[2] != idx) {
+		upslogx(LOG_WARNING, "Indexes do not match: sent 0x%02X, received 0x%02X",
+			(unsigned)idx, (unsigned)buf[2]);
+		return -1;
+	} else if (buf[3] != cmd) {
+		upslogx(LOG_WARNING, "Commands do not match: sent 0x%02X, received 0x%02X",
+			(unsigned)cmd, (unsigned)buf[3]);
+		return -1;
+	}
+
+	if (data != NULL) {
+		memcpy(data, &buf[1 + BICKER_HEADER], datalen);
+	}
+
+	return datalen;
+}
+
+/**
+ * Receive a packet with a data field of known size.
+ * @param idx     Command index
+ * @param cmd     Command
+ * @param dst     Destination buffer or NULL to discard the data field
+ * @param datalen The expected size of the data field
+ * @return        `datalen` on success or -1 on errors.
+ *
+ * `dst`, if not NULL, must have at least `datalen` bytes. If the data
+ * is not exactly `datalen` bytes, an error is thrown.
+ */
+static ssize_t bicker_receive_known(uint8_t idx, uint8_t cmd, void *dst, size_t datalen)
+{
+	ssize_t ret;
+	uint8_t data[BICKER_MAXDATA];
+
+	ret = bicker_receive(idx, cmd, data);
+	if (ret < 0) {
+		return ret;
+	}
+
+	if (datalen != (size_t)ret) {
+		upslogx(LOG_ERR, "Data size does not match: expected %"
+			PRIuSIZE " but got %" PRIiSIZE " bytes",
+			datalen, ret);
+		return -1;
+	}
+
+	if (dst != NULL) {
+		memcpy(dst, data, datalen);
+	}
+
+	return datalen;
+}
+
+/**
+ * Receive the response of a set/get parameter command.
+ * @param id  Id of the parameter
+ * @param dst Where to store the response or NULL to discard
+ * @return The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_receive_parameter(uint8_t id, BickerParameter *dst)
+{
+	ssize_t ret;
+	uint8_t data[10];
+	BickerParameter parameter;
+
+	if (!bicker_valid_id(id, "bicker_receive_parameter")) {
+		return -1;
+	}
+
+	ret = bicker_receive_known(0x07, id, data, sizeof(data));
+	if (ret < 0) {
+		return ret;
+	}
+
+	/* The returned `data` is in the format:
+	 *   [AA] [bbBB] [ccCC] [ddDD] [EE] [ffFF]
+	 * where:
+	 *   [AA]   = parameter id (Byte)
+	 *   [BBbb] = minimum value (UInt16)
+	 *   [CCcc] = maximum value (UInt16)
+	 *   [DDdd] = standard value (UInt16)
+	 *   [EE]   = enabled (Bool)
+	 *   [FFff] = value (UInt16)
+	 */
+	parameter.id = data[0];
+	parameter.min = WORDLH(data[1], data[2]);
+	parameter.max = WORDLH(data[3], data[4]);
+	parameter.std = WORDLH(data[5], data[6]);
+	parameter.enabled = data[7];
+	parameter.value = WORDLH(data[8], data[9]);
+
+	upsdebugx(3, "Parameter %u = %u (%s, min = %u, max = %u, std = %u)",
+		  (unsigned)parameter.id, (unsigned)parameter.value,
+		  parameter.enabled ? "enabled" : "disabled",
+		  (unsigned)parameter.min, (unsigned)parameter.max,
+		  (unsigned)parameter.std);
+
+	if (dst != NULL) {
+		memcpy(dst, &parameter, sizeof(parameter));
+	}
+
+	return ret;
+}
+
+/**
+ * Execute a command that returns an uint8_t value.
+ * @param idx Command index
+ * @param cmd Command
+ * @param dst Destination for the value
+ * @return    The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_read_uint8(uint8_t idx, uint8_t cmd, uint8_t *dst)
+{
+	ssize_t ret;
+
+	ret = bicker_send(idx, cmd, NULL, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+	return bicker_receive_known(idx, cmd, dst, 1);
+}
+
+/**
+ * Execute a command that returns an uint16_t value.
+ * @param idx Command index
+ * @param cmd Command
+ * @param dst Destination for the value or NULL to discard
+ * @return    The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_read_uint16(uint8_t idx, uint8_t cmd, uint16_t *dst)
+{
+	ssize_t ret;
+	uint8_t data[2];
+
+	ret = bicker_send(idx, cmd, NULL, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+	ret = bicker_receive_known(idx, cmd, data, 2);
+	if (ret < 0) {
+		return ret;
+	}
+
+	if (dst != NULL) {
+		*dst = WORDLH(data[0], data[1]);
+	}
+
+	return ret;
+}
+
+/**
+ * Execute a command that returns an int16_t value.
+ * @param idx Command index
+ * @param cmd Command
+ * @param dst Destination for the value or NULL to discard
+ * @return    The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_read_int16(uint8_t idx, uint8_t cmd, int16_t *dst)
+{
+	return bicker_read_uint16(idx, cmd, (uint16_t *) dst);
+}
+
+/**
+ * Execute a command that returns a string.
+ * @param idx Command index
+ * @param cmd Command
+ * @param dst Destination for the string or NULL to discard
+ * @return    The size of the data field on success or -1 on errors.
+ *
+ * `dst`, if not NULL, must have at least BICKER_MAXDATA+1 bytes, the
+ * additional byte needed to accomodate the ending '\0'.
+ */
+static ssize_t bicker_read_string(uint8_t idx, uint8_t cmd, char *dst)
+{
+	ssize_t ret;
+
+	ret = bicker_send(idx, cmd, NULL, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+	ret = bicker_receive(idx, cmd, dst);
+	if (ret < 0) {
+		return ret;
+	}
+
+	dst[ret] = '\0';
+	return ret;
+}
+
+/**
+ * Create a read-write Bicker parameter.
+ * @param parameter Source information
+ * @param mapping   How that parameter is mapped to NUT
+ */
+static void bicker_new(const BickerParameter *parameter, const BickerMapping *mapping)
+{
+	const char *varname;
+
+	varname = mapping->nut_name;
+	if (parameter->enabled) {
+		dstate_setinfo(varname, "%u", (unsigned)parameter->value);
+	} else {
+		/* dstate_setinfo(varname, "") triggers a GCC warning */
+		dstate_setinfo(varname, "%s", "");
+	}
+
+	/* Using ST_FLAG_STRING so an empty string can be used
+	 * to identify a disabled parameter */
+	dstate_setflags(varname, ST_FLAG_RW | ST_FLAG_STRING);
+
+	/* Just tested it: setting a range does not hinder setting
+	 * an empty string with `dstate_setinfo(varname, "")` */
+	if (parameter->min == BICKER_MAXVAL) {
+		/* The device here is likely corrupt:
+		 * apply a standard range to try using it anyway */
+		upslogx(LOG_WARNING, "Parameter %s is corrupt", varname);
+		dstate_addrange(varname, 0, BICKER_MAXVAL);
+	} else {
+		dstate_addrange(varname, parameter->min, parameter->max);
+	}
+
+	/* Maximum value for an uint16_t is 65535, i.e. 5 digits */
+	dstate_setaux(varname, 5);
+}
+
+/**
+ * Get a Bicker parameter.
+ * @param id  Id of the parameter
+ * @param dst Where to store the response or NULL to discard
+ * @return The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_get(uint8_t id, BickerParameter *dst)
+{
+	ssize_t ret;
+
+	if (!bicker_valid_id(id, "bicker_get")) {
+		return -1;
+	}
+
+	ret = bicker_send(0x07, id, NULL, 0);
+	if (ret < 0) {
+		return ret;
+	}
+
+	return bicker_receive_parameter(id, dst);
+}
+
+/**
+ * Set a Bicker parameter.
+ * @param id      Id of the parameter
+ * @param enabled 0 to disable, 1 to enable
+ * @param value   What to set in the value field
+ * @param dst     Where to store the response or NULL to discard
+ * @return The size of the data field on success or -1 on errors.
+ */
+static ssize_t bicker_set(uint8_t id, uint8_t enabled, uint16_t value, BickerParameter *dst)
+{
+	ssize_t ret;
+	uint8_t data[3];
+
+	if (!bicker_valid_id(id, "bicker_set")) {
+		return -1;
+	} else if (enabled > 1) {
+		upslogx(LOG_ERR, "bicker_set(0x%02X, %d, %u): enabled must be 0 or 1",
+			(unsigned)id, enabled, (unsigned)value);
+		return -1;
+	}
+
+	/* Format of `data` is "[EE] [ffFF]"
+	 * where:
+	 *   [EE]   = enabled (Bool)
+	 *   [FFff] = value (UInt16)
+	 */
+	data[0] = enabled;
+	data[1] = LOWBYTE(value);
+	data[2] = HIGHBYTE(value);
+	ret = bicker_send(0x07, id, data, 3);
+	if (ret < 0) {
+		return ret;
+	}
+
+	return bicker_receive_parameter(id, dst);
+}
+
+/**
+ * Write to a Bicker parameter.
+ * @param id  Id of the parameter
+ * @param val A string with the value to write
+ * @param dst Where to store the response or NULL to discard
+ * @return The size of the data field on success or -1 on errors.
+ *
+ * This function is similar to bicker_set() but accepts string values.
+ * If `val` is NULL or empty, the underlying Bicker parameter is
+ * disabled and reset to its standard value.
+ */
+static int bicker_write(uint8_t id, const char *val, BickerParameter *dst)
+{
+	ssize_t ret;
+	BickerParameter parameter;
+	uint8_t enabled;
+	uint16_t value;
+
+	if (val == NULL || val[0] == '\0') {
+		ret = bicker_get(id, &parameter);
+		if (ret < 0) {
+			return ret;
+		}
+		enabled = 0;
+		value = parameter.std;
+	} else {
+		enabled = 1;
+		value = atoi(val);
+	}
+
+	ret = bicker_set(id, enabled, value, &parameter);
+	if (ret < 0) {
+		return ret;
+	}
+
+	if (dst != NULL) {
+		memcpy(dst, &parameter, sizeof(parameter));
+	}
+
+	return ret;
+}
+
+/* For some reason the `seconds` delay (at least on my UPSIC-2403D)
+ * is not honored: the shutdown is always delayed by 2 seconds. This
+ * fixed delay seems to be independent from the state of the UPS (on
+ * line or on battery) and from the DIP switches setting.
+ *
+ * As response I get the same command with `0xE0` in the data field.
+ */
+static ssize_t bicker_delayed_shutdown(uint8_t seconds)
+{
+	ssize_t ret;
+	uint8_t response;
+
+	ret = bicker_send(0x03, 0x32, &seconds, 1);
+	if (ret < 0) {
+		return ret;
+	}
+
+	ret = bicker_receive_known(0x03, 0x32, &response, 1);
+	if (ret >= 0) {
+		upslogx(LOG_INFO, "Shutting down in %d seconds: response = 0x%02X",
+			seconds, (unsigned)response);
+	}
+
+	return ret;
+}
+
+static ssize_t bicker_shutdown(void)
+{
+	const char *str;
+	int delay;
+
+	str = dstate_getinfo("ups.delay.shutdown");
+	delay = str != NULL ? atoi(str) : 0;
+	if (delay > 255) {
+		upslogx(LOG_WARNING, "Shutdown delay too big: %d > 255",
+			delay);
+		delay = 255;
+	}
+
+	return bicker_delayed_shutdown(delay);
+}
+
+static int bicker_instcmd(const char *cmdname, const char *extra)
+{
+	NUT_UNUSED_VARIABLE(extra);
+
+	if (!strcasecmp(cmdname, "shutdown.return")) {
+		bicker_shutdown();
+	}
+
+	upslogx(LOG_NOTICE, "instcmd: unknown command [%s]", cmdname);
+	return STAT_INSTCMD_UNKNOWN;
+}
+
+static int bicker_setvar(const char *varname, const char *val)
+{
+	const BickerMapping *mapping;
+	unsigned i;
+	BickerParameter parameter;
+
+	/* This should not be needed because when `bicker_write()` is
+	 * successful the `parameter` struct is populated but gcc seems
+	 * not to be smart enough to realize that and errors out with
+	 * "error: ‘parameter...’ may be used uninitialized in this function"
+	 */
+	parameter.id = 0;
+	parameter.min = 0;
+	parameter.max = BICKER_MAXVAL;
+	parameter.std = 0;
+	parameter.enabled = 0;
+	parameter.value = 0;
+
+	/* Handle mapped parameters */
+	for (i = 0; i < SIZEOF_ARRAY(bicker_mappings); ++i) {
+		mapping = &bicker_mappings[i];
+		if (!strcasecmp(varname, mapping->nut_name)) {
+			if (bicker_write(mapping->bicker_id, val, &parameter) < 0) {
+				return STAT_SET_FAILED;
+			}
+
+			if (parameter.enabled) {
+				dstate_setinfo(varname, "%u",
+					       (unsigned)parameter.value);
+			} else {
+				/* Disabled parameters are removed from NUT */
+				dstate_delinfo(varname);
+			}
+			return STAT_SET_HANDLED;
+		}
+	}
+
+	upslogx(LOG_NOTICE, "setvar: unknown variable [%s]", varname);
+	return STAT_SET_UNKNOWN;
+}
+
+void upsdrv_initinfo(void)
+{
+	char string[BICKER_MAXDATA + 1];
+
+	dstate_setinfo("device.type", "ups");
+
+	if (bicker_read_string(0x01, 0x60, string) >= 0) {
+		dstate_setinfo("device.mfr", "%s", string);
+	}
+
+	if (bicker_read_string(0x01, 0x61, string) >= 0) {
+		dstate_setinfo("device.serial", "%s", string);
+	}
+
+	if (bicker_read_string(0x01, 0x62, string) >= 0) {
+		dstate_setinfo("device.model", "%s", string);
+	}
+
+	dstate_addcmd("shutdown.return");
+
+	upsh.instcmd = bicker_instcmd;
+	upsh.setvar = bicker_setvar;
+}
+
+void upsdrv_updateinfo(void)
+{
+	uint8_t u8;
+	uint16_t u16;
+	int16_t i16;
+	ssize_t ret;
+
+	ret = bicker_read_uint16(0x01, 0x41, &u16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("input.voltage", "%.1f", (double) u16 / 1000);
+
+	ret = bicker_read_uint16(0x01, 0x42, &u16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("input.current", "%.3f", (double) u16 / 1000);
+
+	ret = bicker_read_uint16(0x01, 0x43, &u16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("output.voltage", "%.3f", (double) u16 / 1000);
+
+	ret = bicker_read_uint16(0x01, 0x44, &u16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("output.current", "%.3f", (double) u16 / 1000);
+
+	/* This is a supercap UPS so, in this context,
+	 * the "battery" is the supercap stack */
+	ret = bicker_read_uint16(0x01, 0x45, &u16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("battery.voltage", "%.3f", (double) u16 / 1000);
+
+	ret = bicker_read_int16(0x01, 0x46, &i16);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("battery.current", "%.3f", (double) i16 / 1000);
+
+	/* Not implemented for all energy packs: failure acceptable */
+	if (bicker_read_uint16(0x01, 0x4A, &u16) >= 0) {
+		dstate_setinfo("battery.temperature", "%.1f", (double) u16 - 273.16);
+	}
+
+	/* Not implemented for all energy packs: failure acceptable */
+	if (bicker_read_uint8(0x01, 0x48, &u8) >= 0) {
+		dstate_setinfo("battery.status", "%d%%", u8);
+	}
+
+	ret = bicker_read_uint8(0x01, 0x47, &u8);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+	dstate_setinfo("battery.charge", "%d", u8);
+
+	status_init();
+
+	/* In `u8` we already have the battery charge */
+	if (u8 < atoi(dstate_getinfo("battery.charge.low"))) {
+		status_set("LB");
+	}
+
+	/* StatusFlags() returns an 8 bit register:
+	 * 0. Charging
+	 * 1. Discharging
+	 * 2. Power present
+	 * 3. Battery present
+	 * 4. Shutdown received
+	 * 5. Overcurrent
+	 * 6. ---
+	 * 7. ---
+	 */
+	ret = bicker_read_uint8(0x01, 0x40, &u8);
+	if (ret < 0) {
+		dstate_datastale();
+		return;
+	}
+
+	if ((u8 & 0x01) > 0) {
+		status_set("CHRG");
+	}
+	if ((u8 & 0x02) > 0) {
+		status_set("DISCHRG");
+	}
+	dstate_setinfo("battery.charger.status",
+		       (u8 & 0x01) > 0 ? "charging" :
+		       (u8 & 0x02) > 0 ? "discharging" :
+		       "resting");
+
+	status_set((u8 & 0x04) > 0 ? "OL" : "OB");
+	if ((u8 & 0x20) > 0) {
+		status_set("OVER");
+	}
+
+	status_commit();
+
+	dstate_dataok();
+}
+
+void upsdrv_shutdown(void)
+{
+	int retry;
+
+	for (retry = 1; retry <= BICKER_RETRIES; retry++) {
+		if (bicker_shutdown() > 0) {
+			set_exit_flag(-2);	/* EXIT_SUCCESS */
+			return;
+		}
+	}
+
+	upslogx(LOG_ERR, "Shutdown failed!");
+	set_exit_flag(-1);
+}
+
+void upsdrv_help(void)
+{
+}
+
+void upsdrv_makevartable(void)
+{
+}
+
+void upsdrv_initups(void)
+{
+	char string[BICKER_MAXDATA + 1];
+	BickerParameter parameter;
+	const BickerMapping *mapping;
+	unsigned i;
+
+	upsfd = ser_open(device_path);
+	ser_set_speed(upsfd, device_path, B38400);
+	ser_set_dtr(upsfd, 1);
+
+	if (bicker_read_string(0x01, 0x63, string) >= 0) {
+		dstate_setinfo("ups.firmware", "%s", string);
+	}
+
+	if (bicker_read_string(0x01, 0x64, string) >= 0) {
+		dstate_setinfo("battery.type", "%s", string);
+	}
+
+	/* Not implemented on all UPSes */
+	if (bicker_read_string(0x01, 0x65, string) >= 0) {
+		dstate_setinfo("ups.firmware.aux", "%s", string);
+	}
+
+	/* Initialize mapped parameters */
+	for (i = 0; i < SIZEOF_ARRAY(bicker_mappings); ++i) {
+		mapping = &bicker_mappings[i];
+		if (bicker_get(mapping->bicker_id, &parameter) >= 0) {
+			bicker_new(&parameter, mapping);
+		}
+	}
+
+	/* Ensure "battery.charge.low" variable is defined */
+	if (dstate_getinfo("battery.charge.low") == NULL) {
+		dstate_setinfo("battery.charge.low", "%d", 20);
+	}
+}
+
+void upsdrv_cleanup(void)
+{
+	ser_close(upsfd, device_path);
+}
diff --git a/drivers/blazer.c b/drivers/blazer.c
index 230cd9a89e..af224fb5bb 100644
--- a/drivers/blazer.c
+++ b/drivers/blazer.c
@@ -554,7 +554,7 @@ void blazer_makevartable(void)
 	addvar(VAR_FLAG, "norating", "Skip reading rating information from UPS");
 	addvar(VAR_FLAG, "novendor", "Skip reading vendor information from UPS");
 
-	addvar(VAR_FLAG, "protocol", "Preselect communication protocol (skip autodetection)");
+	addvar(VAR_VALUE, "protocol", "Preselect communication protocol (skip autodetection)");
 }
 
 
diff --git a/drivers/blazer_ser.c b/drivers/blazer_ser.c
index f0cd90e4e8..5f830e3e6a 100644
--- a/drivers/blazer_ser.c
+++ b/drivers/blazer_ser.c
@@ -31,7 +31,7 @@
 #include "blazer.h"
 
 #define DRIVER_NAME	"Megatec/Q1 protocol serial driver"
-#define DRIVER_VERSION	"1.60"
+#define DRIVER_VERSION	"1.62"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/blazer_usb.c b/drivers/blazer_usb.c
index 27c5ceecbf..fb0f75a2d5 100644
--- a/drivers/blazer_usb.c
+++ b/drivers/blazer_usb.c
@@ -37,7 +37,7 @@
 #endif
 
 #define DRIVER_NAME	"Megatec/Q1 protocol USB driver"
-#define DRIVER_VERSION	"0.17"
+#define DRIVER_VERSION	"0.20"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -138,6 +138,9 @@ static int phoenix_command(const char *cmd, char *buf, size_t buflen)
 
 		case LIBUSB_ERROR_TIMEOUT: /** Operation or Connection timed out */
 			break;
+
+		default:
+			break;
 		}
 
 		if (ret < 0) {
diff --git a/drivers/clone-outlet.c b/drivers/clone-outlet.c
index 62f3cd186d..791a9648c9 100644
--- a/drivers/clone-outlet.c
+++ b/drivers/clone-outlet.c
@@ -1,7 +1,9 @@
 /*
-* clone-outlet.c: clone outlet UPS driver
+* clone-outlet.c: clone an UPS, treating its outlet as if it were an UPS
+*                 (monitoring only)
 *
 * Copyright (C) 2009 - Arjen de Korte <adkorte-guest@alioth.debian.org>
+* Copyright (C) 2024 - Jim Klimov <jimklimov+nut@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@@ -28,8 +30,8 @@
 #include <sys/un.h>
 #endif
 
-#define DRIVER_NAME	"clone outlet UPS Driver"
-#define DRIVER_VERSION	"0.03"
+#define DRIVER_NAME	"Clone outlet UPS driver"
+#define DRIVER_VERSION	"0.06"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -67,20 +69,20 @@ static struct {
 static int	dumpdone = 0;
 
 static PCONF_CTX_t	sock_ctx;
-static time_t	last_heard = 0, last_ping = 0;
+static time_t	last_poll = 0, last_heard = 0, last_ping = 0;
 
-#ifdef WIN32
-static char     	read_buf[SMALLBUF];
-static OVERLAPPED	read_overlapped;
-#else
+#ifndef WIN32
 /* TODO: Why not built in WIN32? */
 static time_t	last_connfail = 0;
+#else
+static char     	read_buf[SMALLBUF];
+static OVERLAPPED	read_overlapped;
 #endif
 
 static int parse_args(size_t numargs, char **arg)
 {
 	if (numargs < 1) {
-		return 0;
+		goto skip_out;
 	}
 
 	if (!strcasecmp(arg[0], "PONG")) {
@@ -105,7 +107,7 @@ static int parse_args(size_t numargs, char **arg)
 	}
 
 	if (numargs < 2) {
-		return 0;
+		goto skip_out;
 	}
 
 	/* DELINFO <var> */
@@ -115,7 +117,7 @@ static int parse_args(size_t numargs, char **arg)
 	}
 
 	if (numargs < 3) {
-		return 0;
+		goto skip_out;
 	}
 
 	/* SETINFO <varname> <value> */
@@ -147,6 +149,24 @@ static int parse_args(size_t numargs, char **arg)
 		return 1;
 	}
 
+skip_out:
+	if (nut_debug_level > 0) {
+		char	buf[LARGEBUF];
+		size_t	i;
+		int	len = -1;
+
+		memset(buf, 0, sizeof(buf));
+		for (i = 0; i < numargs; i++) {
+			len = snprintfcat(buf, sizeof(buf), "[%s] ", arg[i]);
+		}
+		if (len > 0) {
+			buf[len - 1] = '\0';
+		}
+
+		upsdebugx(3, "%s: ignored protocol line with %" PRIuSIZE " keyword(s): %s",
+			__func__, numargs, numargs < 1 ? "<empty>" : buf);
+	}
+
 	return 0;
 }
 
@@ -154,11 +174,11 @@ static int parse_args(size_t numargs, char **arg)
 static TYPE_FD sstate_connect(void)
 {
 	TYPE_FD	fd;
+	const char	*dumpcmd = "DUMPALL\n";
 
 #ifndef WIN32
 	ssize_t	ret;
 	int	len;
-	const char	*dumpcmd = "DUMPALL\n";
 	struct sockaddr_un	sa;
 
 	memset(&sa, '\0', sizeof(sa));
@@ -234,7 +254,6 @@ static TYPE_FD sstate_connect(void)
 	/* continued below... */
 #else /* WIN32 */
 	char		pipename[SMALLBUF];
-	const char	*dumpcmd = "DUMPALL\n";
 	BOOL		result = FALSE;
 
 	snprintf(pipename, sizeof(pipename), "\\\\.\\pipe\\%s/%s", dflt_statepath(), device_path);
@@ -324,12 +343,12 @@ static int sstate_sendline(const char *buf)
 	DWORD bytesWritten = 0;
 	BOOL  result = FALSE;
 
-	result = WriteFile (upsfd,buf,strlen(buf),&bytesWritten,NULL);
+	result = WriteFile (upsfd, buf, strlen(buf), &bytesWritten, NULL);
 
-	if( result == 0 ) {
+	if (result == 0) {
 		ret = 0;
 	}
-	else  {
+	else {
 		ret = (int)bytesWritten;
 	}
 #endif
@@ -449,6 +468,18 @@ void upsdrv_initinfo(void)
 
 void upsdrv_updateinfo(void)
 {
+	time_t	now = time(NULL);
+	double	d;
+
+	/* Throttle tight loops to avoid CPU burn, e.g. when the socket to driver
+	 * is not in fact connected, so a select() somewhere is not waiting much */
+	if (last_poll > 0 && (d = difftime(now, last_poll)) < 1.0) {
+		upsdebugx(5, "%s: too little time (%g sec) has passed since last cycle, throttling",
+			__func__, d);
+		usleep(500000);
+		now = time(NULL);
+	}
+
 	if (sstate_dead(15)) {
 		sstate_disconnect();
 		extrafd = upsfd = sstate_connect();
@@ -474,6 +505,8 @@ void upsdrv_updateinfo(void)
 
 	upsdebugx(3, "%s: power state not critical", getval("prefix"));
 	dstate_setinfo("ups.status", "%s", ups.status);
+
+	last_poll = now;
 }
 
 
diff --git a/drivers/clone.c b/drivers/clone.c
index 9f963b09a6..b15819eb78 100644
--- a/drivers/clone.c
+++ b/drivers/clone.c
@@ -1,7 +1,9 @@
 /*
-* clone.c: UPS driver clone
+* clone.c: clone an UPS, treating its outlet as if it were an UPS
+*          (with shutdown INSTCMD support)
 *
 * Copyright (C) 2009 - Arjen de Korte <adkorte-guest@alioth.debian.org>
+* Copyright (C) 2024 - Jim Klimov <jimklimov+nut@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
@@ -31,7 +33,7 @@
 #endif
 
 #define DRIVER_NAME	"Clone UPS driver"
-#define DRIVER_VERSION	"0.04"
+#define DRIVER_VERSION	"0.06"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -65,13 +67,14 @@ static int	dumpdone = 0, online = 1, outlet = 1;
 static long	offdelay = 120, ondelay = 30;
 
 static PCONF_CTX_t	sock_ctx;
-static time_t	last_poll = 0, last_heard = 0,
-		last_ping = 0;
+static time_t	last_poll = 0, last_heard = 0, last_ping = 0;
+
 #ifndef WIN32
-static time_t last_connfail = 0;
+/* TODO: Why not built in WIN32? */
+static time_t	last_connfail = 0;
 #else
-static char	read_buf[SMALLBUF];
-static OVERLAPPED read_overlapped;
+static char     	read_buf[SMALLBUF];
+static OVERLAPPED	read_overlapped;
 #endif
 
 static int instcmd(const char *cmdname, const char *extra);
@@ -80,7 +83,7 @@ static int instcmd(const char *cmdname, const char *extra);
 static int parse_args(size_t numargs, char **arg)
 {
 	if (numargs < 1) {
-		return 0;
+		goto skip_out;
 	}
 
 	if (!strcasecmp(arg[0], "PONG")) {
@@ -105,7 +108,7 @@ static int parse_args(size_t numargs, char **arg)
 	}
 
 	if (numargs < 2) {
-		return 0;
+		goto skip_out;
 	}
 
 	/* DELINFO <var> */
@@ -115,7 +118,7 @@ static int parse_args(size_t numargs, char **arg)
 	}
 
 	if (numargs < 3) {
-		return 0;
+		goto skip_out;
 	}
 
 	/* SETINFO <varname> <value> */
@@ -161,6 +164,24 @@ static int parse_args(size_t numargs, char **arg)
 		return 1;
 	}
 
+skip_out:
+	if (nut_debug_level > 0) {
+		char	buf[LARGEBUF];
+		size_t	i;
+		int	len = -1;
+
+		memset(buf, 0, sizeof(buf));
+		for (i = 0; i < numargs; i++) {
+			len = snprintfcat(buf, sizeof(buf), "[%s] ", arg[i]);
+		}
+		if (len > 0) {
+			buf[len - 1] = '\0';
+		}
+
+		upsdebugx(3, "%s: ignored protocol line with %" PRIuSIZE " keyword(s): %s",
+			__func__, numargs, numargs < 1 ? "<empty>" : buf);
+	}
+
 	return 0;
 }
 
@@ -168,11 +189,11 @@ static int parse_args(size_t numargs, char **arg)
 static TYPE_FD sstate_connect(void)
 {
 	TYPE_FD	fd;
+	const char	*dumpcmd = "DUMPALL\n";
 
 #ifndef WIN32
 	ssize_t	ret;
 	int	len;
-	const char	*dumpcmd = "DUMPALL\n";
 	struct sockaddr_un	sa;
 
 	memset(&sa, '\0', sizeof(sa));
@@ -248,7 +269,6 @@ static TYPE_FD sstate_connect(void)
 	/* continued below... */
 #else /* WIN32 */
 	char		pipename[SMALLBUF];
-	const char	*dumpcmd = "DUMPALL\n";
 	BOOL		result = FALSE;
 
 	snprintf(pipename, sizeof(pipename), "\\\\.\\pipe\\%s/%s", dflt_statepath(), device_path);
@@ -338,7 +358,7 @@ static int sstate_sendline(const char *buf)
 	DWORD bytesWritten = 0;
 	BOOL  result = FALSE;
 
-	result = WriteFile (upsfd,buf,strlen(buf),&bytesWritten,NULL);
+	result = WriteFile (upsfd, buf, strlen(buf), &bytesWritten, NULL);
 
 	if (result == 0) {
 		ret = 0;
@@ -373,13 +393,13 @@ static int sstate_readline(void)
 	if (ret < 0) {
 		switch(errno)
 		{
-		case EINTR:
-		case EAGAIN:
-			return 0;
+			case EINTR:
+			case EAGAIN:
+				return 0;
 
-		default:
-			upslog_with_errno(LOG_WARNING, "Read from UPS [%s] failed", device_path);
-			return -1;
+			default:
+				upslog_with_errno(LOG_WARNING, "Read from UPS [%s] failed", device_path);
+				return -1;
 		}
 	}
 #else
@@ -398,19 +418,19 @@ static int sstate_readline(void)
 
 		switch (pconf_char(&sock_ctx, buf[i]))
 		{
-		case 1:
-			if (parse_args(sock_ctx.numargs, sock_ctx.arglist)) {
-				time(&last_heard);
-			}
-			continue;
-
-		case 0:
-			continue;	/* haven't gotten a line yet */
-
-		default:
-			/* parse error */
-			upslogx(LOG_NOTICE, "Parse error on sock: %s", sock_ctx.errmsg);
-			return -1;
+			case 1:
+				if (parse_args(sock_ctx.numargs, sock_ctx.arglist)) {
+					time(&last_heard);
+				}
+				continue;
+
+			case 0:
+				continue;	/* haven't gotten a line yet */
+
+			default:
+				/* parse error */
+				upslogx(LOG_NOTICE, "Parse error on sock: %s", sock_ctx.errmsg);
+				return -1;
 		}
 	}
 
@@ -556,6 +576,16 @@ void upsdrv_initinfo(void)
 void upsdrv_updateinfo(void)
 {
 	time_t	now = time(NULL);
+	double	d;
+
+	/* Throttle tight loops to avoid CPU burn, e.g. when the socket to driver
+	 * is not in fact connected, so a select() somewhere is not waiting much */
+	if (last_poll > 0 && (d = difftime(now, last_poll)) < 1.0) {
+		upsdebugx(5, "%s: too little time (%g sec) has passed since last cycle, throttling",
+			__func__, d);
+		usleep(500000);
+		now = time(NULL);
+	}
 
 	if (sstate_dead(15)) {
 		sstate_disconnect();
diff --git a/drivers/cps-hid.c b/drivers/cps-hid.c
index cbe714e787..651807a454 100644
--- a/drivers/cps-hid.c
+++ b/drivers/cps-hid.c
@@ -4,6 +4,7 @@
  *  2003 - 2008 Arnaud Quette <arnaud.quette@free.fr>
  *  2005 - 2006 Peter Selinger <selinger@users.sourceforge.net>
  *  2020 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
+ *  2024        Alejandro González <me@alegon.dev>
  *
  *  Note: this subdriver was initially generated as a "stub" by the
  *  gen-usbhid-subdriver script. It must be customized.
@@ -31,7 +32,7 @@
 #include "cps-hid.h"
 #include "usb-common.h"
 
-#define CPS_HID_VERSION      "CyberPower HID 0.80"
+#define CPS_HID_VERSION      "CyberPower HID 0.81"
 
 /* Cyber Power Systems */
 #define CPS_VENDORID 0x0764
@@ -77,7 +78,7 @@ static usb_device_id_t cps_usb_device_table[] = {
 	{ USB_DEVICE(CPS_VENDORID, 0x0005), NULL },
 	/* Dynex DX-800U?, CP1200AVR/BC1200D, CP825AVR-G, CP1000AVRLCD, CP1000PFCLCD, CP1500C, CP550HG, etc. */
 	{ USB_DEVICE(CPS_VENDORID, 0x0501), &cps_battery_scale },
-	/* OR2200LCDRM2U, OR700LCDRM1U, PR6000LCDRTXL5U */
+	/* OR2200LCDRM2U, OR700LCDRM1U, PR6000LCDRTXL5U, CP1350EPFCLCD */
 	{ USB_DEVICE(CPS_VENDORID, 0x0601), NULL },
 
 	/* Cyber Energy branded devices by CPS */
@@ -154,12 +155,36 @@ static info_lkp_t cps_battcharge[] = {
 	{ 0, NULL, &cps_battcharge_fun, NULL }
 };
 
+static const char *cps_battstatus_fun(double value)
+{
+	static char	buf[8];
+
+	/* assumes `UPS.PowerSummary.FullChargeCapacity` is in %, which should be for */
+	/* UPSes that conform to the USB HID spec, given how we read `battery.charge` */
+	snprintf(buf, sizeof(buf), "%.0f%%", value);
+
+	return buf;
+}
+
+static info_lkp_t cps_battstatus[] = {
+	{ 0, NULL, &cps_battstatus_fun, NULL }
+};
+
+static info_lkp_t cps_sensitivity_info[] = {
+	{ 0, "low", NULL, NULL },
+	{ 1, "normal", NULL, NULL },
+	{ 2, "high", NULL, NULL },
+	{ 0, NULL, NULL, NULL }
+};
+
 /* --------------------------------------------------------------- */
 /*      Vendor-specific usage table */
 /* --------------------------------------------------------------- */
 
 /* CPS usage table */
 static usage_lkp_t cps_usage_lkp[] = {
+	{ "CPSFirmwareVersion", 0xff0100d0 },
+	{ "CPSInputSensitivity",    0xff010043 },
 	{  NULL, 0x0 }
 };
 
@@ -180,7 +205,6 @@ static hid_info_t cps_hid2nut[] = {
   { "unmapped.ups.powersummary.designcapacity", 0, 0, "UPS.PowerSummary.DesignCapacity", NULL, "%.0f", 0, NULL },
   { "unmapped.ups.powersummary.capacitygranularity1", 0, 0, "UPS.PowerSummary.CapacityGranularity1", NULL, "%.0f", 0, NULL },
   { "unmapped.ups.powersummary.capacitygranularity2", 0, 0, "UPS.PowerSummary.CapacityGranularity2", NULL, "%.0f", 0, NULL },
-  { "unmapped.ups.powersummary.fullchargecapacity", 0, 0, "UPS.PowerSummary.FullChargeCapacity", NULL, "%.0f", 0, NULL },
 #endif	/* if WITH_UNMAPPED_DATA_POINTS */
 
   /* Battery page */
@@ -194,17 +218,22 @@ static hid_info_t cps_hid2nut[] = {
   { "battery.runtime.low", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.PowerSummary.RemainingTimeLimit", NULL, "%.0f", HU_FLAG_SEMI_STATIC, NULL },
   { "battery.voltage.nominal", 0, 0, "UPS.PowerSummary.ConfigVoltage", NULL, "%.0f", 0, NULL },
   { "battery.voltage", 0, 0, "UPS.PowerSummary.Voltage", NULL, "%s", 0, cps_battvolt },
+  { "battery.status", 0, 0, "UPS.PowerSummary.FullChargeCapacity", NULL, "%s", 0, cps_battstatus },
 
   /* UPS page */
   { "ups.load", 0, 0, "UPS.Output.PercentLoad", NULL, "%.0f", 0, NULL },
   { "ups.beeper.status", 0, 0, "UPS.PowerSummary.AudibleAlarmControl", NULL, "%s", 0, beeper_info },
   { "ups.test.result", 0, 0, "UPS.Output.Test", NULL, "%s", 0, test_read_info },
+  { "ups.power", 0, 0, "UPS.Output.ApparentPower", NULL, "%.0f", 0, NULL },
+  { "ups.power.nominal", 0, 0, "UPS.Output.ConfigApparentPower", NULL, "%.0f", 0, NULL },
+  { "ups.realpower", 0, 0, "UPS.Output.ActivePower", NULL, "%.0f", 0, NULL },
   { "ups.realpower.nominal", 0, 0, "UPS.Output.ConfigActivePower", NULL, "%.0f", 0, NULL },
   { "ups.delay.start", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Output.DelayBeforeStartup", NULL, DEFAULT_ONDELAY, HU_FLAG_ABSENT, NULL},
   { "ups.delay.shutdown", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Output.DelayBeforeShutdown", NULL, DEFAULT_OFFDELAY, HU_FLAG_ABSENT, NULL},
   { "ups.timer.start", 0, 0, "UPS.Output.DelayBeforeStartup", NULL, "%.0f", HU_FLAG_QUICK_POLL, NULL},
   { "ups.timer.shutdown", 0, 0, "UPS.Output.DelayBeforeShutdown", NULL, "%.0f", HU_FLAG_QUICK_POLL, NULL},
   { "ups.timer.reboot", 0, 0, "UPS.Output.DelayBeforeReboot", NULL, "%.0f", HU_FLAG_QUICK_POLL, NULL},
+  { "ups.firmware", 0, 0, "UPS.PowerSummary.CPSFirmwareVersion", NULL, "%s", HU_FLAG_STATIC, stringid_conversion },
 
   /* Special case: ups.status & ups.alarm */
   { "BOOL", 0, 0, "UPS.PowerSummary.PresentStatus.ACPresent", NULL, NULL, HU_FLAG_QUICK_POLL, online_info },
@@ -222,6 +251,10 @@ static hid_info_t cps_hid2nut[] = {
   { "input.voltage", 0, 0, "UPS.Input.Voltage", NULL, "%.1f", 0, NULL },
   { "input.transfer.low", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Input.LowVoltageTransfer", NULL, "%.0f", HU_FLAG_SEMI_STATIC, NULL },
   { "input.transfer.high", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Input.HighVoltageTransfer", NULL, "%.0f", HU_FLAG_SEMI_STATIC, NULL },
+  /* used by CP1350EPFCLCD */
+  { "input.transfer.low", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Output.LowVoltageTransfer", NULL, "%.0f", HU_FLAG_SEMI_STATIC, NULL },
+  { "input.transfer.high", ST_FLAG_RW | ST_FLAG_STRING, 10, "UPS.Output.HighVoltageTransfer", NULL, "%.0f", HU_FLAG_SEMI_STATIC, NULL },
+  { "input.sensitivity", ST_FLAG_RW | ST_FLAG_STRING, 0, "UPS.Output.CPSInputSensitivity", NULL, "%s", HU_FLAG_SEMI_STATIC | HU_FLAG_ENUM, cps_sensitivity_info },
 
   /* Output page */
   { "output.frequency", 0, 0, "UPS.Output.Frequency", NULL, "%.1f", 0, NULL },
diff --git a/drivers/dstate.c b/drivers/dstate.c
index 43b48719d5..f6edaf616a 100644
--- a/drivers/dstate.c
+++ b/drivers/dstate.c
@@ -3,7 +3,8 @@
    Copyright (C)
 	2003		Russell Kroll <rkroll@exploits.org>
 	2008		Arjen de Korte <adkorte-guest@alioth.debian.org>
-	2012 - 2017	Arnaud Quette <arnaud.quette@free.fr>
+	2012-2017	Arnaud Quette <arnaud.quette@free.fr>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -24,15 +25,15 @@
 
 #include <stdio.h>
 #ifndef WIN32
-#include <stdarg.h>
-#include <sys/stat.h>
-#include <pwd.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/un.h>
+# include <stdarg.h>
+# include <sys/stat.h>
+# include <pwd.h>
+# include <sys/types.h>
+# include <sys/socket.h>
+# include <sys/un.h>
 #else
-#include <strings.h>
-#include "wincompat.h"
+# include <strings.h>
+# include "wincompat.h"
 #endif
 
 #include "common.h"
@@ -105,6 +106,9 @@ static void sock_fail(const char *fn)
 		printf(" - rm %s\n\n", dflt_statepath());
 		printf(" - mkdir %s\n", dflt_statepath());
 		break;
+
+	default:
+		break;
 	}
 
 	/*
@@ -202,6 +206,7 @@ static TYPE_FD sock_open(const char *fn)
 static void sock_disconnect(conn_t *conn)
 {
 #ifndef WIN32
+	upsdebugx(3, "%s: disconnecting socket %d", __func__, (int)conn->fd);
 	close(conn->fd);
 #else
 	/* FIXME not sure if this is the right way to close a connection */
@@ -209,11 +214,14 @@ static void sock_disconnect(conn_t *conn)
 		CloseHandle(conn->read_overlapped.hEvent);
 		conn->read_overlapped.hEvent = INVALID_HANDLE_VALUE;
 	}
+	upsdebugx(3, "%s: disconnecting named pipe handle %p", __func__, conn->fd);
 	DisconnectNamedPipe(conn->fd);
 #endif
 
+	upsdebugx(5, "%s: finishing parsing context", __func__);
 	pconf_finish(&conn->ctx);
 
+	upsdebugx(5, "%s: relinking the chain of connections", __func__);
 	if (conn->prev) {
 		conn->prev->next = conn->next;
 	} else {
@@ -226,6 +234,7 @@ static void sock_disconnect(conn_t *conn)
 		/* conntail = conn->prev; */
 	}
 
+	upsdebugx(5, "%s: freeing the conn object", __func__);
 	free(conn);
 }
 
@@ -281,7 +290,7 @@ static void send_to_all(const char *fmt, ...)
 
 		result = WriteFile (conn->fd, buf, buflen, &bytesWritten, NULL);
 		if( result == 0 ) {
-			upsdebugx(2, "write failed on handle %p, disconnecting", conn->fd);
+			upsdebugx(2, "%s: write failed on handle %p, disconnecting", __func__, conn->fd);
 			sock_disconnect(conn);
 			continue;
 		}
@@ -300,7 +309,7 @@ static void send_to_all(const char *fmt, ...)
 				"handle %p failed (ret=%" PRIiSIZE "), disconnecting: %s",
 				__func__, buflen, conn->fd, ret, strerror(errno));
 #endif
-			upsdebugx(6, "failed write: %s", buf);
+			upsdebugx(6, "%s: failed write: %s", __func__, buf);
 
 			sock_disconnect(conn);
 
@@ -426,7 +435,7 @@ static int send_to_one(conn_t *conn, const char *fmt, ...)
 			"handle %p failed (ret=%" PRIiSIZE "), disconnecting: %s",
 			__func__, buflen, conn->fd, ret, strerror(errno));
 #endif
-		upsdebugx(6, "failed write: %s", buf);
+		upsdebugx(6, "%s: failed write: %s", __func__, buf);
 		sock_disconnect(conn);
 
 		/* TOTHINK: Maybe fallback elsewhere in other cases? */
@@ -474,7 +483,7 @@ static void sock_connect(TYPE_FD sock)
 	fd = accept(sock, (struct sockaddr *) &sa, &salen);
 
 	if (INVALID_FD(fd)) {
-		upslog_with_errno(LOG_ERR, "accept on unix fd failed");
+		upslog_with_errno(LOG_ERR, "%s: accept on unix fd failed", __func__);
 		return;
 	}
 
@@ -490,7 +499,7 @@ static void sock_connect(TYPE_FD sock)
 		ret = fcntl(fd, F_GETFL, 0);
 
 		if (ret < 0) {
-			upslog_with_errno(LOG_ERR, "fcntl get on unix fd failed");
+			upslog_with_errno(LOG_ERR, "%s: fcntl get on unix fd failed", __func__);
 			close(fd);
 			return;
 		}
@@ -498,7 +507,7 @@ static void sock_connect(TYPE_FD sock)
 		ret = fcntl(fd, F_SETFL, ret | O_NDELAY);
 
 		if (ret < 0) {
-			upslog_with_errno(LOG_ERR, "fcntl set O_NDELAY on unix fd failed");
+			upslog_with_errno(LOG_ERR, "%s: fcntl set O_NDELAY on unix fd failed", __func__);
 			close(fd);
 			return;
 		}
@@ -507,7 +516,7 @@ static void sock_connect(TYPE_FD sock)
 		upsdebugx(0, "%s: keeping default synchronous mode", __func__);
 	}
 
-	conn = xcalloc(1, sizeof(*conn));
+	conn = (conn_t *)xcalloc(1, sizeof(*conn));
 	conn->fd = fd;
 
 #else /* WIN32 */
@@ -569,6 +578,8 @@ static void sock_connect(TYPE_FD sock)
 #endif
 
 	conn->nobroadcast = 0;
+	conn->readzero = 0;
+	conn->closing = 0;
 	pconf_init(&conn->ctx, NULL);
 
 	if (connhead) {
@@ -579,31 +590,18 @@ static void sock_connect(TYPE_FD sock)
 	connhead = conn;
 
 #ifndef WIN32
-	upsdebugx(3, "new connection on fd %d", fd);
+	upsdebugx(3, "%s: new connection on fd %d", __func__, fd);
 #else
-	upsdebugx(3, "new connection on handle %p", sock);
+	upsdebugx(3, "%s: new connection on handle %p", __func__, sock);
 #endif
 
 }
 
-static int st_tree_dump_conn(st_tree_t *node, conn_t *conn)
+static int st_tree_dump_conn_one_node(st_tree_t *node, conn_t *conn)
 {
-	int	ret;
 	enum_t	*etmp;
 	range_t	*rtmp;
 
-	if (!node) {
-		return 1;	/* not an error */
-	}
-
-	if (node->left) {
-		ret = st_tree_dump_conn(node->left, conn);
-
-		if (!ret) {
-			return 0;	/* write failed in the child */
-		}
-	}
-
 	if (!send_to_one(conn, "SETINFO %s \"%s\"\n", node->var, node->val)) {
 		return 0;	/* write failed, bail out */
 	}
@@ -651,6 +649,28 @@ static int st_tree_dump_conn(st_tree_t *node, conn_t *conn)
 		}
 	}
 
+	return 1;	/* everything's OK here ... */
+}
+
+static int st_tree_dump_conn(st_tree_t *node, conn_t *conn)
+{
+	int	ret;
+
+	if (!node) {
+		return 1;	/* not an error */
+	}
+
+	if (node->left) {
+		ret = st_tree_dump_conn(node->left, conn);
+
+		if (!ret) {
+			return 0;	/* write failed in the child */
+		}
+	}
+
+	if (!st_tree_dump_conn_one_node(node, conn))
+		return 0;	/* one of writes failed, bail out */
+
 	if (node->right) {
 		return st_tree_dump_conn(node->right, conn);
 	}
@@ -683,26 +703,60 @@ static int sock_arg(conn_t *conn, size_t numarg, char **arg)
 	char *sockfn = pipename;	/* Just for the report below; not a global var in WIN32 builds */
 #endif
 
-	upsdebugx(6, "Driver on %s is now handling %s with %" PRIuSIZE " args",
-		sockfn, numarg ? arg[0] : "<skipped: no command>", numarg);
+	upsdebugx(6, "%s: Driver on %s is now handling %s with %" PRIuSIZE " args",
+		__func__, sockfn, numarg ? arg[0] : "<skipped: no command>", numarg);
 
 	if (numarg < 1) {
 		return 0;
 	}
 
-	if (!strcasecmp(arg[0], "DUMPALL")) {
+	if (!strcasecmp(arg[0], "LOGOUT")) {
+		send_to_one(conn, "OK Goodbye\n");
+#ifndef WIN32
+		upsdebugx(2, "%s: received LOGOUT on socket %d, will be disconnecting", __func__, (int)conn->fd);
+#else
+		upsdebugx(2, "%s: received LOGOUT on handle %p, will be disconnecting", __func__, conn->fd);
+#endif
+		/* Let the system flush the reply somehow (or the other
+		 * side to just see it) before we drop the pipe */
+		usleep(1000000);
+		/* err on the safe side, and actually close/free conn separately */
+		conn->closing = 1;
+		upsdebugx(4, "%s: LOGOUT processing finished", __func__);
+		return 2;
+	}
+
+	if (!strcasecmp(arg[0], "GETPID")) {
+		send_to_one(conn, "PID %" PRIiMAX "\n", (intmax_t)getpid());
+		return 1;
+	}
 
+	if (!strcasecmp(arg[0], "DUMPALL") || !strcasecmp(arg[0], "DUMPSTATUS") || (!strcasecmp(arg[0], "DUMPVALUE") && numarg > 1)) {
 		/* first thing: the staleness flag (see also below) */
 		if ((stale == 1) && !send_to_one(conn, "DATASTALE\n")) {
 			return 1;
 		}
 
-		if (!st_tree_dump_conn(dtree_root, conn)) {
-			return 1;
-		}
+		if (!strcasecmp(arg[0], "DUMPALL")) {
+			if (!st_tree_dump_conn(dtree_root, conn)) {
+				return 1;
+			}
 
-		if (!cmd_dump_conn(conn)) {
-			return 1;
+			if (!cmd_dump_conn(conn)) {
+				return 1;
+			}
+		} else {
+			/* A cheaper version of the dump */
+			char	*varname = (!strcasecmp(arg[0], "DUMPSTATUS") ? "ups.status" : (numarg > 1 ? arg[1] : NULL));
+			st_tree_t	*sttmp = (varname ? state_tree_find(dtree_root, varname) : NULL);
+
+			if (!sttmp) {
+				upsdebugx(1, "%s: %s was requested but currently no %s is known",
+					__func__, arg[0], NUT_STRARG(varname));
+			} else {
+				if (!st_tree_dump_conn_one_node(sttmp, conn))
+					return 1;
+			}
 		}
 
 		if ((stale == 0) && !send_to_one(conn, "DATAOK\n")) {
@@ -872,6 +926,7 @@ static int sock_arg(conn_t *conn, size_t numarg, char **arg)
 static void sock_read(conn_t *conn)
 {
 	ssize_t	ret, i;
+	int	ret_arg = -1;
 
 #ifndef WIN32
 	char	buf[SMALLBUF];
@@ -890,6 +945,39 @@ static void sock_read(conn_t *conn)
 			return;
 		}
 	}
+
+	if (ret == 0) {
+		int	flags = fcntl(conn->fd, F_GETFL), is_closed = 0;
+		upsdebugx(2, "%s: read() returned 0; flags=%04X O_NDELAY=%04X", __func__, flags, O_NDELAY);
+		if (flags & O_NDELAY || O_NDELAY == 0) {
+			/* O_NDELAY with zero bytes means nothing to read but
+			 * since read() follows a successful select() with
+			 * ready file descriptor, ret shouldn't be 0.
+			 * This may also mean that the counterpart has exited
+			 * and the file descriptor should be reaped.
+			 * e.g. a `driver -c reload -a testups` fires its
+			 * message over Unix socket and disconnects.
+			 */
+			is_closed = 1;
+		} else {
+			/* assume we will soon have data waiting in the buffer */
+			conn->readzero++;
+			upsdebugx(1, "%s: got zero-sized reads %d times in a row", __func__, conn->readzero);
+			if (conn->readzero > DSTATE_CONN_READZERO_THROTTLE_MAX) {
+				is_closed = 2;
+			} else {
+				usleep(DSTATE_CONN_READZERO_THROTTLE_USEC);
+			}
+		}
+
+		if (is_closed) {
+			upsdebugx(1, "%s: it seems the other side has closed the connection", __func__);
+			sock_disconnect(conn);
+			return;
+		}
+	} else {
+		conn->readzero = 0;
+	}
 #else
 	char *buf = conn->buf;
 	DWORD bytesRead;
@@ -917,7 +1005,8 @@ static void sock_read(conn_t *conn)
 			continue;
 
 		case 1: /* try to use it, and complain about unknown commands */
-			if (!sock_arg(conn, conn->ctx.numargs, conn->ctx.arglist)) {
+			ret_arg = sock_arg(conn, conn->ctx.numargs, conn->ctx.arglist);
+			if (!ret_arg) {
 				size_t	arg;
 
 				upslogx(LOG_INFO, "Unknown command on socket: ");
@@ -925,7 +1014,13 @@ static void sock_read(conn_t *conn)
 				for (arg = 0; arg < conn->ctx.numargs && arg < INT_MAX; arg++) {
 					upslogx(LOG_INFO, "arg %d: %s", (int)arg, conn->ctx.arglist[arg]);
 				}
+			} else if (ret_arg == 2) {
+				/* closed by LOGOUT processing, conn is free()'d */
+				if (i < ret)
+					upsdebugx(1, "%s: returning early, socket may be not valid anymore", __func__);
+				return;
 			}
+
 			continue;
 
 		default: /* nothing parsed */
@@ -1002,9 +1097,9 @@ char * dstate_init(const char *prog, const char *devname)
 	sockfd = sock_open(sockname);
 
 #ifndef WIN32
-	upsdebugx(2, "dstate_init: sock %s open on fd %d", sockname, sockfd);
+	upsdebugx(2, "%s: sock %s open on fd %d", __func__, sockname, sockfd);
 #else
-	upsdebugx(2, "dstate_init: sock %s open on handle %p", sockname, sockfd);
+	upsdebugx(2, "%s: sock %s open on handle %p", __func__, sockname, sockfd);
 #endif
 
 	/* NOTE: Caller must free this string */
@@ -1016,13 +1111,12 @@ int dstate_poll_fds(struct timeval timeout, TYPE_FD arg_extrafd)
 {
 	int	maxfd = 0; /* Unidiomatic use vs. "sockfd" below, which is "int" on non-WIN32 */
 	int	overrun = 0;
-	conn_t	*conn;
+	conn_t	*conn, *cnext;
 	struct timeval	now;
 
 #ifndef WIN32
 	int	ret;
 	fd_set	rfds;
-	conn_t	*cnext;
 
 	FD_ZERO(&rfds);
 	FD_SET(sockfd, &rfds);
@@ -1077,7 +1171,7 @@ int dstate_poll_fds(struct timeval timeout, TYPE_FD arg_extrafd)
 			break;
 
 		default:
-			upslog_with_errno(LOG_ERR, "select unix sockets failed");
+			upslog_with_errno(LOG_ERR, "%s: select unix sockets failed", __func__);
 		}
 
 		return overrun;
@@ -1095,6 +1189,14 @@ int dstate_poll_fds(struct timeval timeout, TYPE_FD arg_extrafd)
 		}
 	}
 
+	for (conn = connhead; conn; conn = cnext) {
+		cnext = conn->next;
+
+		if (conn->closing) {
+			sock_disconnect(conn);
+		}
+	}
+
 	/* tell the caller if that fd woke up */
 	if (VALID_FD(arg_extrafd) && (FD_ISSET(arg_extrafd, &rfds))) {
 		return 1;
@@ -1154,7 +1256,7 @@ int dstate_poll_fds(struct timeval timeout, TYPE_FD arg_extrafd)
 	}
 
 	if (ret == WAIT_FAILED) {
-		upslog_with_errno(LOG_ERR, "waitfor failed");
+		upslog_with_errno(LOG_ERR, "%s: waitfor failed", __func__);
 		return overrun;
 	}
 
@@ -1176,6 +1278,14 @@ int dstate_poll_fds(struct timeval timeout, TYPE_FD arg_extrafd)
 		}
 	}
 
+	for (conn = connhead; conn; conn = cnext) {
+		cnext = conn->next;
+
+		if (conn->closing) {
+			sock_disconnect(conn);
+		}
+	}
+
 	/* tell the caller if that fd woke up */
 /*
 	if (VALID_FD(arg_extrafd) && (ret == arg_extrafd)) {
@@ -1355,7 +1465,7 @@ void dstate_setaux(const char *var, long aux)
 	sttmp = state_tree_find(dtree_root, var);
 
 	if (!sttmp) {
-		upslogx(LOG_ERR, "dstate_setaux: base variable (%s) does not exist", var);
+		upslogx(LOG_ERR, "%s: base variable (%s) does not exist", __func__, var);
 		return;
 	}
 
@@ -1510,6 +1620,36 @@ void status_init(void)
 	memset(status_buf, 0, sizeof(status_buf));
 }
 
+/* check if a status element has been set, return 0 if not, 1 if yes
+ * (considering a whole-word token in temporary status_buf) */
+int status_get(const char *buf)
+{
+	char	*s = NULL;
+	size_t	offset = 0, buflen = 0;
+
+	if (!buf || !*buf || !*status_buf)
+		return 0;
+
+	s = strstr(status_buf, buf);
+	buflen = strlen(buf);
+
+	/* not found */
+	if (!s)
+		return 0;
+
+	offset = status_buf - s;
+	if (offset == 0 || status_buf[offset - 1] == ' ') {
+		/* We have hit the start of token */
+		if (s[buflen] == '\0' || s[buflen] == ' ') {
+			/* And we have hit the end of token */
+			return 1;
+		}
+	}
+
+	/* buf was a substring of some other token */
+	return 0;
+}
+
 /* add a status element */
 void status_set(const char *buf)
 {
@@ -1518,6 +1658,11 @@ void status_set(const char *buf)
 		return;
 	}
 
+	if (status_get(buf)) {
+		upsdebugx(2, "%s: status was already set: %s", __func__, buf);
+		return;
+	}
+
 	/* separate with a space if multiple elements are present */
 	if (strlen(status_buf) > 0) {
 		snprintfcat(status_buf, sizeof(status_buf), " %s", buf);
@@ -1675,9 +1820,15 @@ void alarm_set(const char *buf)
 # pragma GCC diagnostic pop
 #endif
 
-/* write the status_buf into the info array */
+/* write the status_buf into the info array for "ups.alarm" */
 void alarm_commit(void)
 {
+	/* Note this is a bit different from `device_alarm_commit(0);`
+	 * because here we also increase AND zero out the alarm count.
+	 *		alarm_active = 0; device_alarm_commit(0);
+	 * would be equivalent, but too intimate for later maintenance.
+	 */
+
 	if (strlen(alarm_buf) > 0) {
 		dstate_setinfo("ups.alarm", "%s", alarm_buf);
 		alarm_active = 1;
@@ -1694,6 +1845,8 @@ void device_alarm_init(void)
 }
 
 /* same as above, but writes to "device.X.ups.alarm" or "ups.alarm" */
+/* Note that 20 chars below just allow for a 2-digit "X" */
+/* FIXME? Shouldn't this be changed to be a LARGEBUF aka sizeof(alarm_buf) ? */
 void device_alarm_commit(const int device_number)
 {
 	char info_name[20];
diff --git a/drivers/dstate.h b/drivers/dstate.h
index 2fa754defa..bb578f61aa 100644
--- a/drivers/dstate.h
+++ b/drivers/dstate.h
@@ -3,6 +3,7 @@
    Copyright (C)
 	2003	Russell Kroll <rkroll@exploits.org>
 	2012-2017	Arnaud Quette <arnaud.quette@free.fr>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -52,8 +53,16 @@ typedef struct conn_s {
 	struct conn_s	*prev;
 	struct conn_s	*next;
 	int	nobroadcast;	/* connections can request to ignore send_to_all() updates */
+	int	readzero;	/* how many times in a row we had zero bytes read; see DSTATE_CONN_READZERO_THROTTLE_USEC and DSTATE_CONN_READZERO_THROTTLE_MAX */
+	int	closing;	/* raised during LOGOUT processing, to close the socket when time is right */
 } conn_t;
 
+/* sleep after read()ing zero bytes */
+#define DSTATE_CONN_READZERO_THROTTLE_USEC	500
+
+/* close socket after read()ing zero bytes this many times in a row */
+#define DSTATE_CONN_READZERO_THROTTLE_MAX	5
+
 #include "main.h"	/* for set_exit_flag(); uses conn_t itself */
 
 	extern	struct	ups_handler	upsh;
@@ -92,6 +101,10 @@ int dstate_is_stale(void);
 /* clean out the temp space for a new pass */
 void status_init(void);
 
+/* check if a status element has been set, return 0 if not, 1 if yes
+ * (considering a whole-word token in temporary status_buf) */
+int status_get(const char *buf);
+
 /* add a status element */
 void status_set(const char *buf);
 
diff --git a/drivers/dummy-ups.c b/drivers/dummy-ups.c
index 7c3a435f38..939bf16b1b 100644
--- a/drivers/dummy-ups.c
+++ b/drivers/dummy-ups.c
@@ -48,7 +48,7 @@
 #include "dummy-ups.h"
 
 #define DRIVER_NAME	"Device simulation and repeater driver"
-#define DRIVER_VERSION	"0.18"
+#define DRIVER_VERSION	"0.19"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info =
diff --git a/drivers/etapro.c b/drivers/etapro.c
index 2e5fa812ef..6e4f593fe8 100644
--- a/drivers/etapro.c
+++ b/drivers/etapro.c
@@ -55,7 +55,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"ETA PRO driver"
-#define DRIVER_VERSION	"0.06"
+#define DRIVER_VERSION	"0.07"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -106,6 +106,8 @@ etapro_get_response(const char *resp_type)
 	case 'T':
 		dstate_setinfo("ups.mfr.date", "%s", cp + 2);
 		return 0;
+	default:
+		break;
 	}
 	/* Handle all other responses as hexadecimal numbers.  */
 	val = 0;
diff --git a/drivers/everups.c b/drivers/everups.c
index dc032b0fec..6a3b09d57f 100644
--- a/drivers/everups.c
+++ b/drivers/everups.c
@@ -21,7 +21,7 @@
 #include "serial.h"
 
 #define DRIVER_NAME	"Ever UPS driver (serial)"
-#define DRIVER_VERSION	"0.05"
+#define DRIVER_VERSION	"0.06"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/gamatronic.c b/drivers/gamatronic.c
index bf0c6ad333..9c1b6fa6eb 100644
--- a/drivers/gamatronic.c
+++ b/drivers/gamatronic.c
@@ -33,7 +33,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Gamatronic UPS driver"
-#define DRIVER_VERSION	"0.04"
+#define DRIVER_VERSION	"0.06"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -53,13 +53,23 @@ upsdrv_info_t upsdrv_info = {
 #define SER_WAIT_SEC	1	/* allow 3.0 sec for ser_get calls */
 #define SER_WAIT_USEC	0
 
+/* Reasons for this number are lost in history; protocol docs at
+ * https://networkupstools.org/protocols/sec-protocol.html and
+ * https://networkupstools.org/protocols/us9003.html specify 128
+ * bytes as the max data length in a message; +5 chars for meta
+ * data and +1 for `\0` termination yields maybe 134 as the limit.
+ */
+/* FIXME: Some methods get a buffer and assume its length.
+ * This should normally be a parameter! */
+#define GAMATRONIC_BUF_LEN	140
+
 static int sec_upsrecv (char *buf)
 {
 	char lenbuf[4];
 	int ret;
 
-	ser_get_line(upsfd, buf, 140, ENDCHAR, IGNCHARS,SER_WAIT_SEC, SER_WAIT_USEC);
-	if (buf[0] ==  SEC_MSG_STARTCHAR) {
+	ser_get_line(upsfd, buf, GAMATRONIC_BUF_LEN, ENDCHAR, IGNCHARS, SER_WAIT_SEC, SER_WAIT_USEC);
+	if (buf[0] == SEC_MSG_STARTCHAR) {
 		switch (buf[1]) {
 			case SEC_NAK:
 				return(-1);
@@ -69,11 +79,24 @@ static int sec_upsrecv (char *buf)
 				strncpy(lenbuf, buf+2, 3);
 				lenbuf[3] = '\0';
 				ret = atoi(lenbuf);
+				if (ret > GAMATRONIC_BUF_LEN) {
+					upslogx(1, "%s: got a longer response message "
+						"than expected for protocol: %d (%s) > %d",
+						__func__, ret, lenbuf, GAMATRONIC_BUF_LEN);
+					ret = GAMATRONIC_BUF_LEN;
+				}
 				if (ret > 0) {
-					strcpy(buf,buf+5);
+					/* Note: ser_get_line() returns a
+					 * safely zero-terminated string */
+					memmove(buf, buf+5, (GAMATRONIC_BUF_LEN - 5));
 					return(ret);
 				}
-				else return (-2);
+
+				/* else (ret <= 0) : */
+				upslogx(1, "%s: invalid response message length: %s",
+					__func__, lenbuf);
+				return (-2);
+
 			default:
 				return(-2);
 		}
@@ -84,7 +107,7 @@ static int sec_upsrecv (char *buf)
 
 static ssize_t sec_cmd(const char mode, const char *command, char *msgbuf, ssize_t *buflen)
 {
-	char msg[140];
+	char msg[GAMATRONIC_BUF_LEN];
 	ssize_t ret;
 
 	memset(msg, 0, sizeof(msg));
@@ -201,7 +224,7 @@ static void update_pseudovars( void )
 static void sec_poll ( int pollflag ) {
 	ssize_t msglen;
 	int f, q;
-	char retbuf[140], *n, *r;
+	char retbuf[GAMATRONIC_BUF_LEN], *n, *r;
 
 	for (q=0; q<SEC_QUERYLIST_LEN; q++) {
 		if (sec_querylist[q].command == NULL) break;
@@ -348,7 +371,7 @@ void upsdrv_makevartable(void)
 
 static void setup_serial(const char *port)
 {
-	char temp[140];
+	char temp[GAMATRONIC_BUF_LEN];
 	int i;
 	ssize_t ret;
 
diff --git a/drivers/generic_gpio_common.h b/drivers/generic_gpio_common.h
index 3b17a86c9a..5589fc7ec7 100644
--- a/drivers/generic_gpio_common.h
+++ b/drivers/generic_gpio_common.h
@@ -21,7 +21,7 @@
  */
 
 #ifndef GENERIC_GPIO_COMMON_H_SEEN
-#define GENERIC_GPIO_COMMON_H_SEEN
+#define GENERIC_GPIO_COMMON_H_SEEN 1
 
 #include <stdlib.h>
 #include <regex.h>
diff --git a/drivers/generic_gpio_libgpiod.c b/drivers/generic_gpio_libgpiod.c
index dded983b85..ab88271cfc 100644
--- a/drivers/generic_gpio_libgpiod.c
+++ b/drivers/generic_gpio_libgpiod.c
@@ -27,7 +27,7 @@
 #include "generic_gpio_libgpiod.h"
 
 #define DRIVER_NAME	"GPIO UPS driver"
-#define DRIVER_VERSION	"1.01"
+#define DRIVER_VERSION	"1.02"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/generic_gpio_libgpiod.h b/drivers/generic_gpio_libgpiod.h
index 66f13b4511..77deacefb8 100644
--- a/drivers/generic_gpio_libgpiod.h
+++ b/drivers/generic_gpio_libgpiod.h
@@ -21,7 +21,7 @@
  */
 
 #ifndef GENERIC_GPIO_LIBGPIOD_H_SEEN
-#define GENERIC_GPIO_LIBGPIOD_H_SEEN
+#define GENERIC_GPIO_LIBGPIOD_H_SEEN 1
 
 #include <gpiod.h>
 
diff --git a/drivers/generic_modbus.c b/drivers/generic_modbus.c
index b242c5a6a5..c5a9fd5090 100644
--- a/drivers/generic_modbus.c
+++ b/drivers/generic_modbus.c
@@ -27,7 +27,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME "NUT Generic Modbus driver"
-#define DRIVER_VERSION  "0.04"
+#define DRIVER_VERSION  "0.05"
 
 /* variables */
 static modbus_t *mbctx = NULL;                             /* modbus memory context */
diff --git a/drivers/genericups.c b/drivers/genericups.c
index acd2e3f6d6..fe9f1dbc9b 100644
--- a/drivers/genericups.c
+++ b/drivers/genericups.c
@@ -31,7 +31,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Generic contact-closure UPS driver"
-#define DRIVER_VERSION	"1.39"
+#define DRIVER_VERSION	"1.40"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/hidparser.c b/drivers/hidparser.c
index fd52fb3208..a7fb05ec4c 100644
--- a/drivers/hidparser.c
+++ b/drivers/hidparser.c
@@ -350,6 +350,9 @@ static int HIDParse(HIDParser_t *pParser, HIDData_t *pData)
 			/* can't handle long items, but should at least skip them */
 			pParser->Pos += (uint8_t)(pParser->Value & 0xff);
 			break;
+
+		default:
+			break;
 		}
 	} /* while ((Found < 0) && (pParser->Pos < pParser->ReportDescSize)) */
 
diff --git a/drivers/hidparser.h b/drivers/hidparser.h
index 07b9f267aa..6d82927bd5 100644
--- a/drivers/hidparser.h
+++ b/drivers/hidparser.h
@@ -23,7 +23,7 @@
  * -------------------------------------------------------------------------- */
 
 #ifndef NUT_HID_PARSER_H_SEEN
-#define NUT_HID_PARSER_H_SEEN
+#define NUT_HID_PARSER_H_SEEN 1
 
 
 #ifdef __cplusplus
@@ -32,7 +32,14 @@ extern "C" {
 /* *INDENT-ON* */
 #endif /* __cplusplus */
 
-#include "config.h"
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
+
 #include "hidtypes.h"
 
 /* Include "usb-common.h" or "libshut.h" as appropriate, to define the 
diff --git a/drivers/huawei-ups2000.c b/drivers/huawei-ups2000.c
index 9ebf86ff28..403eb1bdcd 100644
--- a/drivers/huawei-ups2000.c
+++ b/drivers/huawei-ups2000.c
@@ -51,7 +51,7 @@
 #include "timehead.h"   /* fallback gmtime_r() variants if needed (e.g. some WIN32) */
 
 #define DRIVER_NAME	"NUT Huawei UPS2000 (1kVA-3kVA) RS-232 Modbus driver"
-#define DRIVER_VERSION	"0.05"
+#define DRIVER_VERSION	"0.07"
 
 #define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
 #define MODBUS_SLAVE_ID 1
@@ -1035,6 +1035,9 @@ static int ups2000_update_alarm(void)
 				case ALARM_CLEAR_DEPENDING:
 					upslogx(loglevel, "This alarm is auto or manual cleared "
 							  "depending on the specific problem.");
+					break;
+				default:
+					break;
 				}
 
 				ups2000_alarm[i].active = 1;
@@ -1858,7 +1861,7 @@ static time_t time_seek(time_t t, int seconds)
 	if (!t)
 		fatalx(EXIT_FAILURE, "time_seek() failed!");
 
-	if (!gmtime_r(&t, &time_tm))
+	if (gmtime_r(&t, &time_tm) == NULL)
 		fatalx(EXIT_FAILURE, "time_seek() failed!");
 
 	time_tm.tm_sec += seconds;
diff --git a/drivers/hwmon_ina219.c b/drivers/hwmon_ina219.c
new file mode 100644
index 0000000000..988208a2a1
--- /dev/null
+++ b/drivers/hwmon_ina219.c
@@ -0,0 +1,476 @@
+/* hwmon.c Driver for INA219 hwmon-based power monitors.
+
+	Copyright (C) 2024 Jan Viktorin <jan.viktorin@gmail.com>
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation; either version 2 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the Free Software
+	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "main.h"
+#include "nut_float.h"
+#include "nut_stdint.h"
+
+#include <dirent.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+
+#ifndef STRFY0
+#	define STRFY0(x) #x
+#endif
+#ifndef STRFY
+#	define STRFY(x) STRFY0(x)
+#endif
+
+#define SYSFS_HWMON_DIR                     "/sys/class/hwmon"
+#define BATTERY_CHARGE_LOW                  15
+#define DRIVER_NAME                         "hwmon-INA219 UPS driver"
+#define DRIVER_VERSION                      "0.01"
+
+upsdrv_info_t upsdrv_info = {
+	DRIVER_NAME,
+	DRIVER_VERSION,
+	"Jan Viktorin <jan.viktorin@gmail.com>",
+	DRV_EXPERIMENTAL,
+	{ NULL },
+};
+
+/**
+ * @brief Path usually pointing to /sys/class/hwmon/hwmonX.
+ */
+static char ina219_base_path[PATH_MAX];
+
+/**
+ * @brief Threshold for detection of LB status.
+ */
+static unsigned int battery_charge_low = BATTERY_CHARGE_LOW;
+
+/**
+ * @brief Battery voltage (mV) when it is considered depleted.
+ */
+static unsigned int battery_voltage_min;
+
+/**
+ * @brief Battery voltage (mV) when it is considered fully charged.
+ */
+static unsigned int battery_voltage_max;
+
+/**
+ * @brief Voltage value as recently read from in1_input (mV).
+ * @see https://docs.kernel.org/hwmon/ina2xx.html
+ */
+static int voltage = 0;
+
+/**
+ * @brief Current value as recently read from curr1_input (mA).
+ * @see https://docs.kernel.org/hwmon/ina2xx.html
+ */
+static int current = 0;
+
+static int file_contains(const char *path, const char *text)
+{
+	FILE *f;
+	char buf[128];
+	size_t len;
+
+	if ((f = fopen(path, "r")) == NULL) {
+		upslog_with_errno(LOG_ERR, "unable to open %s", path);
+		return 0;
+	}
+
+	len = fread(buf, 1, sizeof(buf), f);
+	fclose(f);
+	upsdebugx(4, "read %" PRIuSIZE " bytes", len);
+
+	if (strlen(text) != len)
+		return 0;
+
+	if (memcmp(buf, text, len))
+		return 0;
+
+	return 1;
+}
+
+static int file_read_number(const char *path, int *value)
+{
+	char buf[128];
+	ssize_t ret;
+	int fd;
+
+	if ((fd = open(path, O_RDONLY)) < 0)
+		return -errno;
+
+	if ((ret = pread(fd, buf, sizeof(buf), 0)) < 0) {
+		const int _e = -errno;
+		close(fd);
+		return _e;
+	}
+	else {
+		close(fd);
+
+		buf[ret] = '\0';
+		*value = atoi(buf);
+		return 0;
+	}
+}
+
+static int detect_ina219(const char *ina219_dir)
+{
+	char namepath[PATH_MAX];
+
+	upsdebugx(3, "checking %s", ina219_dir);
+
+	snprintf(namepath, sizeof(namepath), "%s/name", ina219_dir);
+
+	if (!file_contains(namepath, "ina219\n"))
+		return -ENODEV;
+
+	upsdebugx(3, "detected ina219 at %s", ina219_dir);
+	return 0;
+}
+
+static int scan_hwmon_ina219(const char *sysfs_hwmon_dir)
+{
+	DIR *sysfs;
+	struct dirent *entry;
+	int ret;
+
+	if (strcmp(device_path, "auto")) {
+		if ((ret = detect_ina219(device_path)) < 0) {
+			fatal_with_errno(EXIT_FAILURE,
+					"not a valid hwmon ina219 dir: '%s'\n", device_path);
+		}
+
+		snprintf(ina219_base_path, sizeof(ina219_base_path), "%s", device_path);
+		return 0;
+	}
+
+	upslogx(LOG_NOTICE, "scanning %s for ina219", sysfs_hwmon_dir);
+
+	if ((sysfs = opendir(sysfs_hwmon_dir)) == NULL) {
+		const int _e = -errno;
+		upslog_with_errno(LOG_ERR, "unable to open %s", sysfs_hwmon_dir);
+		return _e;
+	}
+
+	while ((entry = readdir(sysfs)) != NULL) {
+		char hwmon_dir[PATH_MAX];
+
+		if (entry->d_type != DT_DIR && entry->d_type != DT_LNK) {
+			upsdebugx(3, "path %s/%s is not directory/symlink", sysfs_hwmon_dir,
+					entry->d_name);
+			continue;
+		}
+
+		if (!strcmp(entry->d_name, ".") || !strcmp(entry->d_name, "..")) {
+			upsdebugx(3, "skipping path %s/%s", sysfs_hwmon_dir, entry->d_name);
+			continue;
+		}
+
+		snprintf(hwmon_dir, sizeof(hwmon_dir), "%s/%s",
+					sysfs_hwmon_dir, entry->d_name);
+		if (detect_ina219(hwmon_dir) < 0) {
+			/* Log this one only if really troubleshooting,
+			 * this is quite an anticipated and noisy situation,
+			 * to disregard most of the directories in sysfs :)
+			 */
+			upsdebugx(6, "skipping path %s: not the expected subsystem", hwmon_dir);
+			continue;
+		}
+
+		snprintf(ina219_base_path, sizeof(ina219_base_path), "%s", hwmon_dir);
+		closedir(sysfs);
+		return 0;
+	}
+
+	closedir(sysfs);
+	return -ENODEV;
+}
+
+static int update_intvar(
+	const char *base_path,
+	const char *name,
+	int *value)
+{
+	char path[PATH_MAX];
+	int ret;
+
+	if (snprintf(path, sizeof(path), "%s/%s", base_path, name) >= PATH_MAX) {
+		errno = ENAMETOOLONG;
+		upslog_with_errno(LOG_ERR, "snprintf(%s/%s) has failed", base_path, name);
+		return -ENAMETOOLONG;
+	}
+
+	if ((ret = file_read_number(path, value)) < 0) {
+		errno = -ret;
+		upslog_with_errno(LOG_ERR, "file_read_number(%s) has failed", path);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int update_voltage(void)
+{
+	return update_intvar(ina219_base_path, "in1_input", &voltage);
+}
+
+static int update_current(void)
+{
+	return update_intvar(ina219_base_path, "curr1_input", &current);
+}
+
+void upsdrv_makevartable(void)
+{
+	addvar(VAR_VALUE, "sysfs_dir",
+			"Path to sysfs dir of hwmon if port=auto (" SYSFS_HWMON_DIR ")");
+}
+
+static int parse_voltage(const char *s, double *v)
+{
+	errno = 0;
+	*v = strtod(s, NULL);
+
+	if (errno)
+		return -errno;
+
+	if (!isnormal(*v) || !isfinite(*v))
+		return -EDOM;
+
+	return 0;
+}
+
+static void battery_voltage_params_init(void)
+{
+	/* Note: with this device, we do not really expect these values
+	 * to be reported by hardware or change over time, so this is
+	 * only parsed (from built-in or user-provided defaults) into
+	 * C variables once.
+	 */
+	const char *d_min = dstate_getinfo("battery.voltage.low");
+	const char *d_max = dstate_getinfo("battery.voltage.high");
+	double volt_nominal;
+	int ret;
+
+	if (!d_min || !d_max) {
+		const char *d_nom;
+
+		d_nom = dstate_getinfo("battery.voltage.nominal");
+		upsdebugx(4, "battery.voltage.nominal = '%s'\n", d_nom);
+
+		if (d_nom == NULL) {
+			volt_nominal = 3.6;
+		}
+		else {
+			if ((ret = parse_voltage(d_nom, &volt_nominal)) < 0) {
+				errno = -ret;
+				fatal_with_errno(EXIT_FAILURE,
+						"battery.voltage.nominal is invalid: '%s'\n", d_nom);
+			}
+		}
+
+		upslogx(LOG_NOTICE,
+				"guess battery params from battery.voltage.nominal = %.1lf V\n",
+				volt_nominal);
+
+		if (d_equal(volt_nominal, 3.6)) {
+			battery_voltage_min = 3000;
+			battery_voltage_max = 4250;
+		}
+		else if (d_equal(volt_nominal, 3.7)) {
+			battery_voltage_min = 3000;
+			battery_voltage_max = 4250;
+		}
+		else if (d_equal(volt_nominal, 3.8)) {
+			battery_voltage_min = 3000;
+			battery_voltage_max = 4350;
+		}
+		else if (d_equal(volt_nominal, 3.85)) {
+			battery_voltage_min = 3000;
+			battery_voltage_max = 4400;
+		}
+		else {
+			fatalx(EXIT_FAILURE, "unsupported battery.voltage.nominal: %lf\n",
+					volt_nominal);
+		}
+	}
+	else {
+		double tmp;
+
+		if ((ret = parse_voltage(d_min, &tmp)) < 0) {
+			errno = -ret;
+			fatal_with_errno(EXIT_FAILURE,
+					"invalid battery.voltage.low: '%s'\n", d_min);
+		}
+		else {
+			battery_voltage_min = (unsigned int) (tmp * 1000.0);
+		}
+
+		if ((ret = parse_voltage(d_max, &tmp)) < 0) {
+			errno = -ret;
+			fatal_with_errno(EXIT_FAILURE,
+					"invalid battery.voltage.high: '%s'\n", d_max);
+		}
+		else {
+			battery_voltage_max = (unsigned int) (tmp * 1000.0);
+		}
+	}
+
+	upslogx(LOG_NOTICE, "battery.voltage.low = %u mV\n", battery_voltage_min);
+	upslogx(LOG_NOTICE, "battery.voltage.high = %u mV\n", battery_voltage_max);
+}
+
+static int parse_charge(const char *s, unsigned int *v)
+{
+	long tmp;
+
+	errno = 0;
+	tmp = strtol(s, NULL, 0);
+
+	if (errno)
+		return -errno;
+
+	if (tmp < 1 || tmp > 100)
+		return -ERANGE;
+
+	*v = (int) tmp;
+	return 0;
+}
+
+static void battery_charge_params_init(void)
+{
+	const char *v_lb = dstate_getinfo("battery.charge.low");
+	int ret;
+
+	if (v_lb) {
+		if ((ret = parse_charge(v_lb, &battery_charge_low)) < 0) {
+			errno = -ret;
+			fatal_with_errno(EXIT_FAILURE,
+					"battery.charge.low is invalid: '%s'", v_lb);
+		}
+	}
+
+	upslogx(LOG_NOTICE, "battery.charge.low = %u\n", battery_charge_low);
+}
+
+void upsdrv_initups(void)
+{
+	const char *hwmon_dir = SYSFS_HWMON_DIR;
+	int ret;
+
+	if (getval("sysfs_dir"))
+		hwmon_dir = getval("sysfs_dir");
+
+	if ((ret = scan_hwmon_ina219(hwmon_dir)) < 0) {
+		errno = -ret;
+		fatal_with_errno(EXIT_FAILURE, "scan_hwmon_ina219(%s) has failed",
+				hwmon_dir);
+	}
+
+	battery_voltage_params_init();
+	battery_charge_params_init();
+}
+
+void upsdrv_initinfo(void)
+{
+	dstate_setinfo("ups.mfr", "%s", "Texas Instruments");
+	dstate_setinfo("ups.model", "%s", "INA219");
+	dstate_setinfo("ups.type", "%s", "ups");
+	dstate_setinfo("device.mfr", "%s", "Texas Instruments");
+	dstate_setinfo("device.model", "%s", "INA219");
+	dstate_setinfo("device.type", "%s", "ups");
+	dstate_setinfo("device.description", "%s",
+			"Bidirectional Current/Power Monitor With I2C Interface");
+
+	dstate_setinfo("battery.charge.low", "%d", battery_charge_low);
+}
+
+static unsigned int battery_charge_compute(void)
+{
+	const double divisor = (battery_voltage_max - battery_voltage_min) / 100.0;
+	double charge;
+
+	if (voltage < 0)
+		return 0;
+
+	if (((unsigned int) voltage) > battery_voltage_min)
+		charge = voltage - battery_voltage_min;
+	else
+		charge = 0;
+
+	charge /= divisor;
+	charge = charge > 100 ? 100 : charge;
+
+	return (unsigned int) charge;
+}
+
+void upsdrv_updateinfo(void)
+{
+	unsigned int charge = 0;
+	int stale = 0;
+
+	if (update_voltage() < 0)
+		stale = 1;
+
+	upsdebugx(3, "Battery voltage: %.3fV", voltage / 1000.0);
+
+	if (update_current() < 0)
+		stale = 1;
+
+	upsdebugx(3, "Battery current: %.3fA", current / 1000.0);
+
+	if (stale) {
+		dstate_datastale();
+		return;
+	}
+
+	status_init();
+
+	charge = battery_charge_compute();
+
+	status_set(current <= 0 ? "OL" : "OB");
+
+	if (current < 0)
+		status_set("CHRG");
+	else if (current > 0)
+		status_set("DISCHRG");
+
+	if (charge <= battery_charge_low)
+		status_set("LB");
+
+	dstate_setinfo("battery.voltage", "%.3f", voltage / 1000.0);
+	dstate_setinfo("battery.current", "%.3f", current / 1000.0);
+	dstate_setinfo("battery.charge", "%d", charge);
+
+	if (charge <= battery_charge_low && current > 0)
+		dstate_setinfo("battery.runtime", "%d", 60); // 1 minute
+
+	status_commit();
+	dstate_dataok();
+}
+
+void upsdrv_shutdown(void)
+{
+	upslogx(LOG_ERR, "shutdown not supported");
+	set_exit_flag(-1);
+}
+
+void upsdrv_help(void)
+{
+	/* No special options in this driver (vars/flags are auto-documented) */
+}
+
+void upsdrv_cleanup(void)
+{
+}
diff --git a/drivers/isbmex.c b/drivers/isbmex.c
index 923b46f7ee..eff64b12f1 100644
--- a/drivers/isbmex.c
+++ b/drivers/isbmex.c
@@ -22,12 +22,12 @@
 
 #include "main.h"
 #include "serial.h"
+#include "nut_float.h"	/* For sqrt() */
 
-#include <math.h>		/* for sqrt */
 #include <string.h>
 
 #define DRIVER_NAME	"ISBMEX UPS driver"
-#define DRIVER_VERSION	"0.08"
+#define DRIVER_VERSION	"0.10"
 
 /* driver description structure */
 upsdrv_info_t	upsdrv_info = {
diff --git a/drivers/ivtscd.c b/drivers/ivtscd.c
index 3a07c72281..318e09c241 100644
--- a/drivers/ivtscd.c
+++ b/drivers/ivtscd.c
@@ -25,7 +25,7 @@
 #include "attribute.h"
 
 #define DRIVER_NAME	"IVT Solar Controller driver"
-#define DRIVER_VERSION	"0.04"
+#define DRIVER_VERSION	"0.05"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/libhid.c b/drivers/libhid.c
index 74b9991973..5ba17b1f0f 100644
--- a/drivers/libhid.c
+++ b/drivers/libhid.c
@@ -1,6 +1,6 @@
 /*!
  * @file libhid.c
- * @brief HID Library - User API (Generic HID Access using MGE HIDParser)
+ * @brief NUT HID Library - User API (Generic HID Access using MGE HIDParser)
  *
  * @author Copyright (C) 2003 - 2007
  *	Arnaud Quette <arnaud.quette@free.fr> && <arnaud.quette@mgeups.com>
@@ -39,7 +39,7 @@
 #ifdef HAVE_STRINGS_H
 # include <strings.h>
 #endif
-/* #include <math.h> */
+/* #include "nut_float.h" */
 #include "libhid.h"
 #include "hidparser.h"
 #include "common.h" /* for xmalloc, upsdebugx prototypes */
@@ -47,10 +47,10 @@
 
 /* Communication layers and drivers (USB and MGE SHUT) */
 #if (defined SHUT_MODE) && SHUT_MODE
-	#include "libshut.h"
+#	include "libshut.h"
 	communication_subdriver_t *comm_driver = &shut_subdriver;
 #else	/* !SHUT_MODE => USB */
-	#include "nut_libusb.h"
+#	include "nut_libusb.h"
 	communication_subdriver_t *comm_driver = &usb_subdriver;
 #endif	/* SHUT_MODE / USB */
 
@@ -239,7 +239,7 @@ static int refresh_report_buffer(reportbuf_t *rbuf, hid_dev_handle_t udev, HIDDa
 	r = (size_t)ret;
 
 	if (rbuf->len[id] != r) {
-		/* e.g. if maxreportsize flag was set */
+		/* e.g. if max_report_size flag was set */
 		upsdebugx(2,
 			"%s: expected %" PRIuSIZE " bytes, but got %" PRIuSIZE " instead",
 			__func__, rbuf->len[id], r);
diff --git a/drivers/libhid.h b/drivers/libhid.h
index 613fda9aae..4a916a6fb4 100644
--- a/drivers/libhid.h
+++ b/drivers/libhid.h
@@ -1,6 +1,6 @@
 /*!
  * @file libhid.h
- * @brief HID Library - User API
+ * @brief NUT HID Library - User API
  *
  * @author Copyright (C) 2003 - 2007
  *      Arnaud Quette <arnaud.quette@free.fr> && <arnaud.quette@mgeups.com>
@@ -27,9 +27,15 @@
  * -------------------------------------------------------------------------- */
 
 #ifndef NUT_LIBHID_H_SEEN
-#define NUT_LIBHID_H_SEEN
-
-#include "config.h"
+#define NUT_LIBHID_H_SEEN 1
+
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #include <sys/types.h>
 #include "nut_stdint.h"
@@ -38,19 +44,19 @@
 #include "timehead.h"
 
 #if (defined SHUT_MODE) && SHUT_MODE
-	#include "libshut.h"
+#	include "libshut.h"
 	typedef SHUTDevice_t                   HIDDevice_t;
 	typedef char                           HIDDeviceMatcher_t;
 	typedef usb_dev_handle                 hid_dev_handle_t;
 	typedef shut_communication_subdriver_t communication_subdriver_t;
-	#define HID_DEV_HANDLE_CLOSED          (hid_dev_handle_t)(ERROR_FD_SER)
+#	define HID_DEV_HANDLE_CLOSED          (hid_dev_handle_t)(ERROR_FD_SER)
 #else	/* !SHUT_MODE => USB */
-	#include "nut_libusb.h" /* includes usb-common.h */
+#	include "nut_libusb.h" /* includes usb-common.h */
 	typedef USBDevice_t                   HIDDevice_t;
 	typedef USBDeviceMatcher_t            HIDDeviceMatcher_t;
 	typedef usb_dev_handle *              hid_dev_handle_t;
 	typedef usb_communication_subdriver_t communication_subdriver_t;
-	#define HID_DEV_HANDLE_CLOSED          (hid_dev_handle_t)(NULL)
+#	define HID_DEV_HANDLE_CLOSED          (hid_dev_handle_t)(NULL)
 #endif	/* SHUT_MODE / USB */
 
 /* use explicit booleans */
diff --git a/drivers/libshut.c b/drivers/libshut.c
index 3601c0c344..7a9f78bd34 100644
--- a/drivers/libshut.c
+++ b/drivers/libshut.c
@@ -43,7 +43,7 @@
 #include "common.h" /* for xmalloc, upsdebugx prototypes */
 
 #define SHUT_DRIVER_NAME	"SHUT communication driver"
-#define SHUT_DRIVER_VERSION	"0.88"
+#define SHUT_DRIVER_VERSION	"0.89"
 
 /* communication driver description structure */
 upsdrv_info_t comm_upsdrv_info = {
@@ -376,15 +376,10 @@ static int libshut_open(
 		            usb_ctrl_charbuf rdbuf, usb_ctrl_charbufsize rdlen))
 {
 	int ret, res;
-	/* Below we cast this buffer as sometimes containing entried of type
-	 * "struct device_descriptor_s" or "struct my_hid_descriptor".
-	 * Currently both of these are sized "2", and I don't see a way
-	 * to require a "max()" of such sizes to align for generally.
-	 */
 	usb_ctrl_char buf[20] __attribute__((aligned(4)));
 	char string[MAX_STRING_SIZE];
-	struct my_hid_descriptor *desc;
-	struct device_descriptor_s *dev_descriptor;
+	struct my_hid_descriptor	desc_buf, *desc = &desc_buf;
+	struct device_descriptor_s	dev_descriptor_buf, *dev_descriptor = &dev_descriptor_buf;
 
 	/* report descriptor */
 	usb_ctrl_char	rdbuf[MAX_REPORT_SIZE];
@@ -394,6 +389,50 @@ static int libshut_open(
 	 * version is at index 1 (in which case, bcdDevice == 0x0202) */
 	usb_ctrl_descindex	hid_desc_index = 0;
 
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-type-limit-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#pragma clang diagnostic ignored "-Wtautological-compare"
+#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+	static int usb_hid_number_opts_parsed = 0;
+	if (!usb_hid_number_opts_parsed) {
+		const char *s;
+		unsigned short us = 0;
+		if ((s = getval("usb_hid_desc_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_DESCINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_desc_index", __func__);
+			}
+			hid_desc_index = (usb_ctrl_descindex)us;
+		}
+		usb_hid_number_opts_parsed = 1;
+	}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic pop
+#endif
+
 	if (!arg_device_path) {
 		fatalx(EXIT_FAILURE, "%s: arg_device_path=null", __func__);
 	}
@@ -426,21 +465,7 @@ static int libshut_open(
 	}
 
 	/* Get DEVICE descriptor */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-#ifdef __clang__
-# pragma clang diagnostic push
-# pragma clang diagnostic ignored "-Wcast-align"
-#endif
-	dev_descriptor = (struct device_descriptor_s *)buf;
-#ifdef __clang__
-# pragma clang diagnostic pop
-#endif
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+	memcpy(dev_descriptor, buf, sizeof(struct device_descriptor_s));
 	res = shut_get_descriptor(*arg_upsfd, USB_DT_DEVICE, 0, buf, USB_DT_DEVICE_SIZE);
 	/* res = shut_control_msg(devp, USB_ENDPOINT_IN+1, USB_REQ_GET_DESCRIPTOR,
 	(USB_DT_DEVICE << 8) + 0, 0, buf, 0x9, SHUT_TIMEOUT); */
@@ -537,26 +562,13 @@ static int libshut_open(
 	upsdebugx(2, "Device matches");
 
 	if ((curDevice->VendorID == 0x463) && (curDevice->bcdDevice == 0x0202)) {
-			upsdebugx(1, "Eaton device v2.02. Using full report descriptor");
+		upsdebugx(1, "Eaton device v2.02. Using full report descriptor");
+		if (!getval("usb_hid_desc_index"))
 			hid_desc_index = 1;
 	}
 
 	/* Get HID descriptor */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-#ifdef __clang__
-# pragma clang diagnostic push
-# pragma clang diagnostic ignored "-Wcast-align"
-#endif
-	desc = (struct my_hid_descriptor *)buf;
-#ifdef __clang__
-# pragma clang diagnostic pop
-#endif
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+	memcpy(desc, buf, sizeof(struct my_hid_descriptor));
 	res = shut_get_descriptor(*arg_upsfd, USB_DT_HID, hid_desc_index, buf, 0x9);
 	/* res = shut_control_msg(devp, USB_ENDPOINT_IN+1, USB_REQ_GET_DESCRIPTOR,
 			(USB_DT_HID << 8) + 0, 0, buf, 0x9, SHUT_TIMEOUT); */
@@ -1271,7 +1283,7 @@ static int shut_control_msg(
 				__func__, data_size);
 			return -1;
 		}
-		if (data_size > 0x0F) {
+		if (data_size > 0x0F || data_size > sizeof(shut_pkt) - 2) {
 			upsdebugx(1, "%s: WARNING: data_size %" PRI_NUT_USB_CTRL_CHARBUFSIZE
 				" may be too large for SHUT packet?",
 				__func__, data_size);
@@ -1281,7 +1293,7 @@ static int shut_control_msg(
 		}
 		shut_pkt[1] = (unsigned char)(data_size<<4) + (unsigned char)data_size;
 		if ( (requesttype == REQUEST_TYPE_SET_REPORT) && (remaining_size < 8) )
-			memcpy(&shut_pkt[2], bytes, data_size); /* we need to send ctrl.data  */
+			memcpy(&shut_pkt[2], bytes, data_size > sizeof(shut_pkt) - 2 ? sizeof(shut_pkt) - 2 : data_size); /* we need to send ctrl.data  */
 		else
 			memcpy(&shut_pkt[2], &ctrl, 8);
 		shut_pkt[(data_size+3) - 1] = shut_checksum(&shut_pkt[2], (unsigned char)data_size);
diff --git a/drivers/libusb0.c b/drivers/libusb0.c
index c713450ba0..1f86740848 100644
--- a/drivers/libusb0.c
+++ b/drivers/libusb0.c
@@ -5,6 +5,7 @@
  * @author Copyright (C)
  *  2003 - 2007 Arnaud Quette <aquette.dev@gmail.com>
  *  2005 - 2007 Peter Selinger <selinger@users.sourceforge.net>
+ *  2021 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  * This program is sponsored by MGE UPS SYSTEMS - opensource.mgeups.com
  *
@@ -37,7 +38,7 @@
 #endif
 
 #define USB_DRIVER_NAME		"USB communication driver (libusb 0.1)"
-#define USB_DRIVER_VERSION	"0.45"
+#define USB_DRIVER_VERSION	"0.48"
 
 /* driver description structure */
 upsdrv_info_t comm_upsdrv_info = {
@@ -49,7 +50,6 @@ upsdrv_info_t comm_upsdrv_info = {
 };
 
 #define MAX_REPORT_SIZE         0x1800
-#define MAX_RETRY               3
 
 #if (!HAVE_STRCASESTR) && (HAVE_STRSTR && HAVE_STRLWR && HAVE_STRDUP)
 /* Only used in this file of all NUT codebase, so not in str.{c,h}
@@ -59,7 +59,7 @@ upsdrv_info_t comm_upsdrv_info = {
 static char *strcasestr(const char *haystack, const char *needle);
 #endif
 
-static void libusb_close(usb_dev_handle *udev);
+static void nut_libusb_close(usb_dev_handle *udev);
 
 /*! Add USB-related driver variables with addvar() and dstate_setinfo().
  * This removes some code duplication across the USB drivers.
@@ -94,6 +94,12 @@ void nut_usb_addvars(void)
 
 	addvar(VAR_VALUE, "usb_set_altinterface", "Force redundant call to usb_set_altinterface() (value=bAlternateSetting; default=0)");
 
+	addvar(VAR_VALUE, "usb_config_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_rep_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_desc_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_ep_in",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_ep_out",	"Deeper tuning of USB communications for complex devices");
+
 	dstate_setinfo("driver.version.usb", "libusb-0.1 (or compat)");
 
 	upsdebugx(1, "Using USB implementation: %s", dstate_getinfo("driver.version.usb"));
@@ -148,7 +154,7 @@ static inline int matches(USBDeviceMatcher_t *matcher, USBDevice_t *device) {
  * devices from working on Mac OS X (presumably the OS is already setting
  * altinterface to 0).
  */
-static int nut_usb_set_altinterface(usb_dev_handle *udev)
+static int nut_libusb_set_altinterface(usb_dev_handle *udev)
 {
 	int altinterface = 0, ret = 0;
 	char *alt_string, *endp = NULL;
@@ -180,6 +186,20 @@ static int nut_usb_set_altinterface(usb_dev_handle *udev)
 	return ret;
 }
 
+static void nut_libusb_subdriver_defaults(usb_communication_subdriver_t *subdriver)
+{
+	if (!getval("usb_config_index"))
+		subdriver->usb_config_index = LIBUSB_DEFAULT_CONF_INDEX;
+	if (!getval("usb_hid_rep_index"))
+		subdriver->hid_rep_index = LIBUSB_DEFAULT_INTERFACE;
+	if (!getval("usb_hid_desc_index"))
+		subdriver->hid_desc_index = LIBUSB_DEFAULT_DESC_INDEX;
+	if (!getval("usb_hid_ep_in"))
+		subdriver->hid_ep_in = LIBUSB_DEFAULT_HID_EP_IN;
+	if (!getval("usb_hid_ep_out"))
+		subdriver->hid_ep_out = LIBUSB_DEFAULT_HID_EP_OUT;
+}
+
 #define usb_control_msg         typesafe_control_msg
 
 /* On success, fill in the curDevice structure and return the report
@@ -190,13 +210,15 @@ static int nut_usb_set_altinterface(usb_dev_handle *udev)
  * is accepted, or < 1 if not. If it isn't accepted, the next device
  * (if any) will be tried, until there are no more devices left.
  */
-static int libusb_open(usb_dev_handle **udevp,
+static int nut_libusb_open(usb_dev_handle **udevp,
 	USBDevice_t *curDevice, USBDeviceMatcher_t *matcher,
 	int (*callback)(usb_dev_handle *udev,
 		USBDevice_t *hd, usb_ctrl_charbuf rdbuf, usb_ctrl_charbufsize rdlen)
 	)
 {
+#ifdef HAVE_USB_DETACH_KERNEL_DRIVER_NP
 	int retries;
+#endif
 	usb_ctrl_charbufsize rdlen1, rdlen2; /* report descriptor length, method 1+2 */
 	USBDeviceMatcher_t *m;
 	struct usb_device *dev;
@@ -219,6 +241,76 @@ static int libusb_open(usb_dev_handle **udevp,
 
 	struct usb_bus *busses;
 
+	static int usb_hid_number_opts_parsed = 0;
+	if (!usb_hid_number_opts_parsed) {
+		const char *s;
+		unsigned short us = 0;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-type-limit-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#pragma clang diagnostic ignored "-Wtautological-compare"
+#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+		if ((s = getval("usb_config_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_CFGINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_config_index", __func__);
+			}
+			usb_subdriver.usb_config_index = (usb_ctrl_cfgindex)us;
+		}
+		if ((s = getval("usb_hid_rep_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_REPINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_rep_index", __func__);
+			}
+			usb_subdriver.hid_rep_index = (usb_ctrl_repindex)us;
+		}
+		if ((s = getval("usb_hid_desc_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_DESCINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_desc_index", __func__);
+			}
+			usb_subdriver.hid_desc_index = (usb_ctrl_descindex)us;
+		}
+		if ((s = getval("usb_hid_ep_in"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_ENDPOINT_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_ep_in", __func__);
+			}
+			usb_subdriver.hid_ep_in = (usb_ctrl_endpoint)us;
+		}
+		if ((s = getval("usb_hid_ep_out"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_ENDPOINT_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_ep_out", __func__);
+			}
+			usb_subdriver.hid_ep_out = (usb_ctrl_endpoint)us;
+		}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic pop
+#endif
+
+		usb_hid_number_opts_parsed = 1;
+	}
+
 	/* libusb base init */
 	usb_init();
 	usb_find_busses();
@@ -236,7 +328,7 @@ static int libusb_open(usb_dev_handle **udevp,
 
 #ifndef __linux__ /* SUN_LIBUSB (confirmed to work on Solaris and FreeBSD) */
 	/* Causes a double free corruption in linux if device is detached! */
-	libusb_close(*udevp);
+	nut_libusb_close(*udevp);
 #endif
 
 	upsdebugx(3, "usb_busses=%p", (void*)usb_busses);
@@ -319,44 +411,32 @@ static int libusb_open(usb_dev_handle **udevp,
 #endif
 
 			if (dev->descriptor.iManufacturer) {
-				retries = MAX_RETRY;
-				while (retries > 0) {
-					ret = usb_get_string_simple(udev, dev->descriptor.iManufacturer,
-						string, sizeof(string));
-					if (ret > 0) {
-						curDevice->Vendor = xstrdup(string);
-						break;
-					}
-					retries--;
-					upsdebugx(1, "%s get iManufacturer failed, retrying...", __func__);
+				ret = nut_usb_get_string(udev, dev->descriptor.iManufacturer,
+					string, sizeof(string));
+				if (ret > 0) {
+					curDevice->Vendor = xstrdup(string);
+				} else {
+					upsdebugx(1, "%s: get Manufacturer string failed", __func__);
 				}
 			}
 
 			if (dev->descriptor.iProduct) {
-				retries = MAX_RETRY;
-				while (retries > 0) {
-					ret = usb_get_string_simple(udev, dev->descriptor.iProduct,
-						string, sizeof(string));
-					if (ret > 0) {
-						curDevice->Product = xstrdup(string);
-						break;
-					}
-					retries--;
-					upsdebugx(1, "%s get iProduct failed, retrying...", __func__);
+				ret = nut_usb_get_string(udev, dev->descriptor.iProduct,
+					string, sizeof(string));
+				if (ret > 0) {
+					curDevice->Product = xstrdup(string);
+				} else {
+					upsdebugx(1, "%s: get Product string failed", __func__);
 				}
 			}
 
 			if (dev->descriptor.iSerialNumber) {
-				retries = MAX_RETRY;
-				while (retries > 0) {
-					ret = usb_get_string_simple(udev, dev->descriptor.iSerialNumber,
-						string, sizeof(string));
-					if (ret > 0) {
-						curDevice->Serial = xstrdup(string);
-						break;
-					}
-					retries--;
-					upsdebugx(1, "%s get iSerialNumber failed, retrying...", __func__);
+				ret = nut_usb_get_string(udev, dev->descriptor.iSerialNumber,
+					string, sizeof(string));
+				if (ret > 0) {
+					curDevice->Serial = xstrdup(string);
+				} else {
+					upsdebugx(1, "%s: get Serial Number string failed", __func__);
 				}
 			}
 
@@ -374,7 +454,8 @@ static int libusb_open(usb_dev_handle **udevp,
 
 			/* FIXME: extend to Eaton OEMs (HP, IBM, ...) */
 			if ((curDevice->VendorID == 0x463) && (curDevice->bcdDevice == 0x0202)) {
-				usb_subdriver.hid_desc_index = 1;
+				if (!getval("usb_hid_desc_index"))
+					usb_subdriver.hid_desc_index = 1;
 			}
 
 			upsdebugx(2, "Trying to match device");
@@ -411,11 +492,10 @@ static int libusb_open(usb_dev_handle **udevp,
 			/* this method requires at least libusb 0.1.8:
 			 * it force device claiming by unbinding
 			 * attached driver... From libhid */
-			retries = MAX_RETRY;
 #ifdef WIN32
 			usb_set_configuration(udev, 1);
 #endif
-
+			retries = 3;
 			while ((ret = usb_claim_interface(udev, usb_subdriver.hid_rep_index)) < 0) {
 				upsdebugx(2, "failed to claim USB device: %s",
 					usb_strerror());
@@ -462,8 +542,12 @@ static int libusb_open(usb_dev_handle **udevp,
 #endif
 			/* if_claimed = 1; */
 
-			nut_usb_set_altinterface(udev);
+			nut_libusb_set_altinterface(udev);
 
+			/* Did the driver provide a callback method for any further
+			 * device acceptance checks (e.g. when same ID is supported
+			 * by several sub-drivers, differing by vendor/model strings)?
+			 */
 			if (!callback) {
 				return 1;
 			}
@@ -618,6 +702,18 @@ static int libusb_open(usb_dev_handle **udevp,
 				"Report descriptor retrieved (Reportlen = %"
 				PRI_NUT_USB_CTRL_CHARBUFSIZE ")", rdlen);
 			upsdebugx(2, "Found HID device");
+
+			upsdebugx(3, "Using default, detected or customized USB HID numbers: "
+				"usb_config_index=%d usb_hid_rep_index=%d "
+				"usb_hid_desc_index=%d "
+				"usb_hid_ep_in=%d usb_hid_ep_out=%d",
+				usb_subdriver.usb_config_index,
+				usb_subdriver.hid_rep_index,
+				usb_subdriver.hid_desc_index,
+				usb_subdriver.hid_ep_in,
+				usb_subdriver.hid_ep_out
+				);
+
 			fflush(stdout);
 
 			return rdlen;
@@ -629,6 +725,8 @@ static int libusb_open(usb_dev_handle **udevp,
 			/* if (if_claimed)
 				usb_release_interface(udev, 0); */
 			usb_close(udev);
+			/* reset any parameters modified by unmatched drivers back to defaults */
+			nut_libusb_subdriver_defaults(&usb_subdriver);
 		}
 	}
 
@@ -657,7 +755,7 @@ static int libusb_open(usb_dev_handle **udevp,
  * Error handler for usb_get/set_* functions. Return value > 0 success,
  * 0 unknown or temporary failure (ignored), < 0 permanent failure (reconnect)
  */
-static int libusb_strerror(const int ret, const char *desc)
+static int nut_libusb_strerror(const int ret, const char *desc)
 {
 	if (ret > 0) {
 		return ret;
@@ -692,6 +790,7 @@ static int libusb_strerror(const int ret, const char *desc)
 		return 0;
 #endif	/* WIN32 */
 
+	case 0: 	/** TOTHINK: Should this (probably LIBUSB_SUCCESS) be quiet? */
 	default:	/* Undetermined, log only */
 		upslogx(LOG_DEBUG, "%s: %s", desc, usb_strerror());
 		return 0;
@@ -703,10 +802,10 @@ static int libusb_strerror(const int ret, const char *desc)
  */
 
 /* Expected evaluated types for the API:
- * static int libusb_get_report(usb_dev_handle *udev,
+ * static int nut_libusb_get_report(usb_dev_handle *udev,
  *	int ReportId, unsigned char *raw_buf, int ReportSize)
  */
-static int libusb_get_report(
+static int nut_libusb_get_report(
 	usb_dev_handle *udev,
 	usb_ctrl_repindex ReportId,
 	usb_ctrl_charbuf raw_buf,
@@ -714,7 +813,7 @@ static int libusb_get_report(
 {
 	int	ret;
 
-	upsdebugx(4, "Entering libusb_get_report");
+	upsdebugx(4, "Entering nut_libusb_get_report");
 
 	if (!udev) {
 		return 0;
@@ -736,14 +835,14 @@ static int libusb_get_report(
 		return 0;
 	}
 
-	return libusb_strerror(ret, __func__);
+	return nut_libusb_strerror(ret, __func__);
 }
 
 /* Expected evaluated types for the API:
- * static int libusb_set_report(usb_dev_handle *udev,
+ * static int nut_libusb_set_report(usb_dev_handle *udev,
  *	int ReportId, unsigned char *raw_buf, int ReportSize)
  */
-static int libusb_set_report(
+static int nut_libusb_set_report(
 	usb_dev_handle *udev,
 	usb_ctrl_repindex ReportId,
 	usb_ctrl_charbuf raw_buf,
@@ -771,14 +870,14 @@ static int libusb_set_report(
 		return 0;
 	}
 
-	return libusb_strerror(ret, __func__);
+	return nut_libusb_strerror(ret, __func__);
 }
 
 /* Expected evaluated types for the API:
- * static int libusb_get_string(usb_dev_handle *udev,
- *	int StringIdx, char *buf, size_t buflen)
+ * static int nut_libusb_get_string(usb_dev_handle *udev,
+ *	int StringIdx, char *buf, int buflen)
  */
-static int libusb_get_string(
+static int nut_libusb_get_string(
 	usb_dev_handle *udev,
 	usb_ctrl_strindex StringIdx,
 	char *buf,
@@ -786,46 +885,43 @@ static int libusb_get_string(
 {
 	int ret;
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic push
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
-# pragma GCC diagnostic ignored "-Wtype-limits"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
-#endif
 	/*
-	 * usb.h:int  usb_get_string_simple(usb_dev_handle *dev, int index,
+	 * usb.h:int  nut_usb_get_string(usb_dev_handle *dev, int index,
 	 * usb.h-         char *buf, size_t buflen);
 	 */
 	if (!udev
-	|| StringIdx < 0 || (uintmax_t)StringIdx > INT_MAX
-	|| buflen < 0 || (uintmax_t)buflen > (uintmax_t)SIZE_MAX
+	|| StringIdx < 1 || StringIdx > 255
+	|| buflen < 1
 	) {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic pop
-#endif
 		return -1;
 	}
 
-	ret = usb_get_string_simple(udev, StringIdx, buf, (size_t)buflen);
+	ret = nut_usb_get_string(udev, StringIdx, buf, (size_t)buflen);
 
 #ifdef WIN32
 	errno = -ret;
 #endif
 
-	return libusb_strerror(ret, __func__);
+	/** 0 can be seen as an empty string, or as a success for
+	 * logging below - also tends to happen */
+	if (ret == 0) {
+		size_t len = strlen(buf);
+		upsdebugx(2, "%s: nut_usb_get_string() returned "
+			"0 (might be just success code), "
+			"actual buf length is %" PRIuSIZE, __func__, len);
+		/* if (len) */
+			return len;
+		/* else may log "nut_libusb_get_string: Success" and return 0 below */
+	}
+
+	return nut_libusb_strerror(ret, __func__);
 }
 
 /* Expected evaluated types for the API:
- * static int libusb_get_interrupt(usb_dev_handle *udev,
+ * static int nut_libusb_get_interrupt(usb_dev_handle *udev,
  *	unsigned char *buf, int bufsize, int timeout)
  */
-static int libusb_get_interrupt(
+static int nut_libusb_get_interrupt(
 	usb_dev_handle *udev,
 	usb_ctrl_charbuf buf,
 	usb_ctrl_charbufsize bufsize,
@@ -849,10 +945,10 @@ static int libusb_get_interrupt(
 		ret = usb_clear_halt(udev, 0x81);
 	}
 
-	return libusb_strerror(ret, __func__);
+	return nut_libusb_strerror(ret, __func__);
 }
 
-static void libusb_close(usb_dev_handle *udev)
+static void nut_libusb_close(usb_dev_handle *udev)
 {
 	if (!udev) {
 		return;
@@ -899,12 +995,12 @@ static char *strcasestr(const char *haystack, const char *needle) {
 usb_communication_subdriver_t usb_subdriver = {
 	USB_DRIVER_NAME,
 	USB_DRIVER_VERSION,
-	libusb_open,
-	libusb_close,
-	libusb_get_report,
-	libusb_set_report,
-	libusb_get_string,
-	libusb_get_interrupt,
+	nut_libusb_open,
+	nut_libusb_close,
+	nut_libusb_get_report,
+	nut_libusb_set_report,
+	nut_libusb_get_string,
+	nut_libusb_get_interrupt,
 	LIBUSB_DEFAULT_CONF_INDEX,
 	LIBUSB_DEFAULT_INTERFACE,
 	LIBUSB_DEFAULT_DESC_INDEX,
diff --git a/drivers/libusb1.c b/drivers/libusb1.c
index c84a28218a..4eac05ca12 100644
--- a/drivers/libusb1.c
+++ b/drivers/libusb1.c
@@ -4,7 +4,7 @@
  *
  * @author Copyright (C) 2016 Eaton
  *         Copyright (C) 2016 Arnaud Quette <aquette.dev@gmail.com>
- *         Copyright (C) 2021 Jim Klimov <jimklimov+nut@gmail.com>
+ *         Copyright (C) 2021-2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  *      The logic of this file is ripped from mge-shut driver (also from
  *      Arnaud Quette), which is a "HID over serial link" UPS driver for
@@ -33,7 +33,7 @@
 #include "nut_stdint.h"
 
 #define USB_DRIVER_NAME		"USB communication driver (libusb 1.0)"
-#define USB_DRIVER_VERSION	"0.46"
+#define USB_DRIVER_VERSION	"0.49"
 
 /* driver description structure */
 upsdrv_info_t comm_upsdrv_info = {
@@ -45,7 +45,6 @@ upsdrv_info_t comm_upsdrv_info = {
 };
 
 #define MAX_REPORT_SIZE         0x1800
-#define MAX_RETRY               3
 
 static void nut_libusb_close(libusb_device_handle *udev);
 
@@ -88,6 +87,12 @@ void nut_usb_addvars(void)
 
 	addvar(VAR_VALUE, "usb_set_altinterface", "Force redundant call to usb_set_altinterface() (value=bAlternateSetting; default=0)");
 
+	addvar(VAR_VALUE, "usb_config_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_rep_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_desc_index",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_ep_in",	"Deeper tuning of USB communications for complex devices");
+	addvar(VAR_VALUE, "usb_hid_ep_out",	"Deeper tuning of USB communications for complex devices");
+
 #ifdef LIBUSB_API_VERSION
 	dstate_setinfo("driver.version.usb", "libusb-%u.%u.%u (API: 0x%x)", v->major, v->minor, v->micro, LIBUSB_API_VERSION);
 #else  /* no LIBUSB_API_VERSION */
@@ -114,7 +119,7 @@ static inline int matches(USBDeviceMatcher_t *matcher, USBDevice_t *device) {
  * devices from working on Mac OS X (presumably the OS is already setting
  * altinterface to 0).
  */
-static int nut_usb_set_altinterface(libusb_device_handle *udev)
+static int nut_libusb_set_altinterface(libusb_device_handle *udev)
 {
 	int altinterface = 0, ret = 0;
 	char *alt_string, *endp = NULL;
@@ -147,6 +152,20 @@ static int nut_usb_set_altinterface(libusb_device_handle *udev)
 	return ret;
 }
 
+static void nut_libusb_subdriver_defaults(usb_communication_subdriver_t *subdriver)
+{
+	if (!getval("usb_config_index"))
+		subdriver->usb_config_index = LIBUSB_DEFAULT_CONF_INDEX;
+	if (!getval("usb_hid_rep_index"))
+		subdriver->hid_rep_index = LIBUSB_DEFAULT_INTERFACE;
+	if (!getval("usb_hid_desc_index"))
+		subdriver->hid_desc_index = LIBUSB_DEFAULT_DESC_INDEX;
+	if (!getval("usb_hid_ep_in"))
+		subdriver->hid_ep_in = LIBUSB_DEFAULT_HID_EP_IN;
+	if (!getval("usb_hid_ep_out"))
+		subdriver->hid_ep_out = LIBUSB_DEFAULT_HID_EP_OUT;
+}
+
 /* On success, fill in the curDevice structure and return the report
  * descriptor length. On failure, return -1.
  * Note: When callback is not NULL, the report descriptor will be
@@ -161,7 +180,9 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 		USBDevice_t *hd, usb_ctrl_charbuf rdbuf, usb_ctrl_charbufsize rdlen)
 	)
 {
+#if (defined HAVE_LIBUSB_DETACH_KERNEL_DRIVER) || (defined HAVE_LIBUSB_DETACH_KERNEL_DRIVER_NP)
 	int retries;
+#endif
 	/* libusb-1.0 usb_ctrl_charbufsize is uint16_t and we
 	 * want the rdlen vars signed - so taking a wider type */
 	int32_t rdlen1, rdlen2; /* report descriptor length, method 1+2 */
@@ -189,6 +210,76 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 	unsigned char	rdbuf[MAX_REPORT_SIZE];
 	int32_t		rdlen;
 
+	static int	usb_hid_number_opts_parsed = 0;
+	if (!usb_hid_number_opts_parsed) {
+		const char	*s;
+		unsigned short	us = 0;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
+# pragma GCC diagnostic ignored "-Wtype-limits"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE
+# pragma GCC diagnostic ignored "-Wtautological-type-limit-compare"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#pragma clang diagnostic ignored "-Wtautological-compare"
+#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+		if ((s = getval("usb_config_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_CFGINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_config_index", __func__);
+			}
+			usb_subdriver.usb_config_index = (usb_ctrl_cfgindex)us;
+		}
+		if ((s = getval("usb_hid_rep_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_REPINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_rep_index", __func__);
+			}
+			usb_subdriver.hid_rep_index = (usb_ctrl_repindex)us;
+		}
+		if ((s = getval("usb_hid_desc_index"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_DESCINDEX_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_desc_index", __func__);
+			}
+			usb_subdriver.hid_desc_index = (usb_ctrl_descindex)us;
+		}
+		if ((s = getval("usb_hid_ep_in"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_ENDPOINT_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_ep_in", __func__);
+			}
+			usb_subdriver.hid_ep_in = (usb_ctrl_endpoint)us;
+		}
+		if ((s = getval("usb_hid_ep_out"))) {
+			if (!str_to_ushort(s, &us, 16) || (us > USB_CTRL_ENDPOINT_MAX)) {
+				fatalx(EXIT_FAILURE, "%s: could not parse usb_hid_ep_out", __func__);
+			}
+			usb_subdriver.hid_ep_out = (usb_ctrl_endpoint)us;
+		}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_TYPE_LIMIT_COMPARE) )
+# pragma GCC diagnostic pop
+#endif
+
+		usb_hid_number_opts_parsed = 1;
+	}
+
 	/* libusb base init */
 	if (libusb_init(NULL) < 0) {
 		libusb_exit(NULL);
@@ -314,56 +405,44 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 		curDevice->bcdDevice = dev_desc.bcdDevice;
 
 		if (dev_desc.iManufacturer) {
-			retries = MAX_RETRY;
-			while (retries > 0) {
-				ret = libusb_get_string_descriptor_ascii(udev, dev_desc.iManufacturer,
-					(unsigned char*)string, sizeof(string));
-				if (ret > 0) {
-					curDevice->Vendor = strdup(string);
-					if (curDevice->Vendor == NULL) {
-						libusb_free_device_list(devlist, 1);
-						fatal_with_errno(EXIT_FAILURE, "Out of memory");
-					}
-					break;
+			ret = nut_usb_get_string(udev, dev_desc.iManufacturer,
+				string, sizeof(string));
+			if (ret > 0) {
+				curDevice->Vendor = strdup(string);
+				if (curDevice->Vendor == NULL) {
+					libusb_free_device_list(devlist, 1);
+					fatal_with_errno(EXIT_FAILURE, "Out of memory");
 				}
-				retries--;
-				upsdebugx(1, "%s get iManufacturer failed, retrying...", __func__);
+			} else {
+				upsdebugx(1, "%s: get Manufacturer string failed", __func__);
 			}
 		}
 
 		if (dev_desc.iProduct) {
-			retries = MAX_RETRY;
-			while (retries > 0) {
-				ret = libusb_get_string_descriptor_ascii(udev, dev_desc.iProduct,
-					(unsigned char*)string, sizeof(string));
-				if (ret > 0) {
-					curDevice->Product = strdup(string);
-					if (curDevice->Product == NULL) {
-						libusb_free_device_list(devlist, 1);
-						fatal_with_errno(EXIT_FAILURE, "Out of memory");
-					}
-					break;
+			ret = nut_usb_get_string(udev, dev_desc.iProduct,
+				string, sizeof(string));
+			if (ret > 0) {
+				curDevice->Product = strdup(string);
+				if (curDevice->Product == NULL) {
+					libusb_free_device_list(devlist, 1);
+					fatal_with_errno(EXIT_FAILURE, "Out of memory");
 				}
-				retries--;
-				upsdebugx(1, "%s get iProduct failed, retrying...", __func__);
+			} else {
+				upsdebugx(1, "%s: get Product string failed", __func__);
 			}
 		}
 
 		if (dev_desc.iSerialNumber) {
-			retries = MAX_RETRY;
-			while (retries > 0) {
-				ret = libusb_get_string_descriptor_ascii(udev, dev_desc.iSerialNumber,
-					(unsigned char*)string, sizeof(string));
-				if (ret > 0) {
-					curDevice->Serial = strdup(string);
-					if (curDevice->Serial == NULL) {
-						libusb_free_device_list(devlist, 1);
-						fatal_with_errno(EXIT_FAILURE, "Out of memory");
-					}
-					break;
+			ret = nut_usb_get_string(udev, dev_desc.iSerialNumber,
+				string, sizeof(string));
+			if (ret > 0) {
+				curDevice->Serial = strdup(string);
+				if (curDevice->Serial == NULL) {
+					libusb_free_device_list(devlist, 1);
+					fatal_with_errno(EXIT_FAILURE, "Out of memory");
 				}
-				retries--;
-				upsdebugx(1, "%s get iSerialNumber failed, retrying...", __func__);
+			} else {
+				upsdebugx(1, "%s: get Serial Number string failed", __func__);
 			}
 		}
 
@@ -381,6 +460,7 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 
 		/* FIXME: extend to Eaton OEMs (HP, IBM, ...) */
 		if ((curDevice->VendorID == 0x463) && (curDevice->bcdDevice == 0x0202)) {
+			if (!getval("usb_hid_desc_index"))
 				usb_subdriver.hid_desc_index = 1;
 		}
 
@@ -455,12 +535,12 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 #if (defined HAVE_LIBUSB_DETACH_KERNEL_DRIVER) || (defined HAVE_LIBUSB_DETACH_KERNEL_DRIVER_NP)
 		/* Then, try the explicit detach method.
 		 * This function is available on FreeBSD 10.1-10.3 */
-		retries = MAX_RETRY;
 #ifdef WIN32
 		/* TODO: Align with libusb1 - initially from Windows branch made against libusb0 */
 		libusb_set_configuration(udev, 1);
 #endif
 
+		retries = 3;
 		while ((ret = libusb_claim_interface(udev, usb_subdriver.hid_rep_index)) != LIBUSB_SUCCESS) {
 			upsdebugx(2, "failed to claim USB device: %s",
 				libusb_strerror((enum libusb_error)ret));
@@ -522,8 +602,12 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 		upsdebugx(2, "Claimed interface %d successfully",
 			usb_subdriver.hid_rep_index);
 
-		nut_usb_set_altinterface(udev);
+		nut_libusb_set_altinterface(udev);
 
+		/* Did the driver provide a callback method for any further
+		 * device acceptance checks (e.g. when same ID is supported
+		 * by several sub-drivers, differing by vendor/model strings)?
+		 */
 		if (!callback) {
 			libusb_free_config_descriptor(conf_desc);
 			libusb_free_device_list(devlist, 1);
@@ -702,6 +786,18 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 
 		upsdebugx(2, "Report descriptor retrieved (Reportlen = %d)", rdlen);
 		upsdebugx(2, "Found HID device");
+
+		upsdebugx(3, "Using default, detected or customized USB HID numbers: "
+			"usb_config_index=%d usb_hid_rep_index=%d "
+			"usb_hid_desc_index=%d "
+			"usb_hid_ep_in=%d usb_hid_ep_out=%d",
+			usb_subdriver.usb_config_index,
+			usb_subdriver.hid_rep_index,
+			usb_subdriver.hid_desc_index,
+			usb_subdriver.hid_ep_in,
+			usb_subdriver.hid_ep_out
+			);
+
 		fflush(stdout);
 		libusb_free_device_list(devlist, 1);
 
@@ -713,6 +809,8 @@ static int nut_libusb_open(libusb_device_handle **udevp,
 			/* if (if_claimed)
 				libusb_release_interface(udev, usb_subdriver.hid_rep_index); */
 			libusb_close(udev);
+			/* reset any parameters modified by unmatched drivers back to defaults */
+			nut_libusb_subdriver_defaults(&usb_subdriver);
 	}
 
 	*udevp = NULL;
@@ -783,6 +881,7 @@ static int nut_libusb_strerror(const int ret, const char *desc)
 		return 0;
 #endif /* WIN32 */
 
+	case LIBUSB_SUCCESS:         /** TOTHINK: Should this be quiet? */
 	case LIBUSB_ERROR_OTHER:     /** Other error */
 	default:                     /** Undetermined, log only */
 		upslogx(LOG_DEBUG, "%s: %s", desc, libusb_strerror((enum libusb_error)ret));
@@ -898,7 +997,7 @@ static int nut_libusb_set_report(
 
 /* Expected evaluated types for the API:
  * static int nut_libusb_get_string(libusb_device_handle *udev,
- *	int StringIdx, char *buf, int buflen)
+ *	uint8_t StringIdx, unsigned char *buf, uint16_t buflen)
  */
 static int nut_libusb_get_string(
 	libusb_device_handle *udev,
@@ -908,30 +1007,24 @@ static int nut_libusb_get_string(
 {
 	int ret;
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic push
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS
-# pragma GCC diagnostic ignored "-Wtype-limits"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-constant-out-of-range-compare"
-#endif
-#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE
-# pragma GCC diagnostic ignored "-Wtautological-unsigned-zero-compare"
-#endif
-	if (!udev
-	|| StringIdx < 0 || (uintmax_t)StringIdx > UINT8_MAX
-	|| buflen < 0 || (uintmax_t)buflen > (uintmax_t)INT_MAX
-	) {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_UNSIGNED_ZERO_COMPARE) )
-# pragma GCC diagnostic pop
-#endif
+	if (!udev || StringIdx < 1 || buflen < 1) {
 		return -1;
 	}
 
-	ret = libusb_get_string_descriptor_ascii(udev, (uint8_t)StringIdx,
-		(unsigned char*)buf, (int)buflen);
+	ret = nut_usb_get_string(udev, (uint8_t)StringIdx,
+		buf, (int)buflen);
+
+	/** 0 can be seen as an empty string, or as LIBUSB_SUCCESS for
+	 * logging below - also tends to happen */
+	if (ret == 0) {
+		size_t len = strlen(buf);
+		upsdebugx(2, "%s: nut_usb_get_string() returned "
+			"0 (might be just LIBUSB_SUCCESS code), "
+			"actual buf length is %" PRIuSIZE, __func__, len);
+		/* if (len) */
+			return len;
+		/* else may log "nut_libusb_get_string: Success" and return 0 below */
+	}
 
 	return nut_libusb_strerror(ret, __func__);
 }
diff --git a/drivers/liebert-esp2.c b/drivers/liebert-esp2.c
index ef27cc871a..10b67b789e 100644
--- a/drivers/liebert-esp2.c
+++ b/drivers/liebert-esp2.c
@@ -28,7 +28,7 @@
 #define IsBitSet(val, bit) ((val) & (1 << (bit)))
 
 #define DRIVER_NAME	"Liebert ESP-II serial UPS driver"
-#define DRIVER_VERSION	"0.06"
+#define DRIVER_VERSION	"0.07"
 
 #define UPS_SHUTDOWN_DELAY 12 /* it means UPS will be shutdown 120 sec */
 #define SHUTDOWN_CMD_LEN  8
diff --git a/drivers/liebert.c b/drivers/liebert.c
index 1c21e6e0da..0c1bc176cc 100644
--- a/drivers/liebert.c
+++ b/drivers/liebert.c
@@ -27,7 +27,7 @@
 #include "attribute.h"
 
 #define DRIVER_NAME	"Liebert MultiLink UPS driver"
-#define DRIVER_VERSION	"1.04"
+#define DRIVER_VERSION	"1.05"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/macosx-ups.c b/drivers/macosx-ups.c
index 1740320c29..b35585ef93 100644
--- a/drivers/macosx-ups.c
+++ b/drivers/macosx-ups.c
@@ -29,7 +29,7 @@
 #include "IOKit/ps/IOPSKeys.h"
 
 #define DRIVER_NAME	"Mac OS X UPS meta-driver"
-#define DRIVER_VERSION	"1.40"
+#define DRIVER_VERSION	"1.41"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/main.c b/drivers/main.c
index 8eb7b08b5c..5c4753a116 100644
--- a/drivers/main.c
+++ b/drivers/main.c
@@ -4,7 +4,7 @@
    1999			Russell Kroll <rkroll@exploits.org>
    2005 - 2017	Arnaud Quette <arnaud.quette@free.fr>
    2017 		Eaton (author: Emilien Kia <EmilienKia@Eaton.com>)
-   2017 - 2022	Jim Klimov <jimklimov+nut@gmail.com>
+   2017 - 2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -139,7 +139,9 @@ void upsdrv_banner (void)
 {
 	int i;
 
-	printf("Network UPS Tools - %s %s (%s)\n", upsdrv_info.name, upsdrv_info.version, UPS_VERSION);
+	printf("Network UPS Tools driver %s - %s %s\n",
+		describe_NUT_VERSION_once(),
+		upsdrv_info.name, upsdrv_info.version);
 
 	/* process sub driver(s) information */
 	for (i = 0; upsdrv_info.subdrv_info[i]; i++) {
@@ -155,6 +157,8 @@ void upsdrv_banner (void)
 		printf("%s %s\n", upsdrv_info.subdrv_info[i]->name,
 			upsdrv_info.subdrv_info[i]->version);
 	}
+
+	fflush(stdout);
 }
 
 #ifndef DRIVERS_MAIN_WITHOUT_MAIN
@@ -178,6 +182,11 @@ static void help_msg(void)
 {
 	vartab_t	*tmp;
 
+	if (banner_is_disabled()) {
+		/* Was not printed at start of main() */
+		upsdrv_banner();
+	}
+
 	nut_report_config_flags();
 
 	printf("\nusage: %s (-a <id>|-s <id>) [OPTIONS]\n", progname);
@@ -227,6 +236,9 @@ static void help_msg(void)
 	printf("                   - reload-or-exit: re-read configuration files (exit the old\n");
 	printf("                     driver instance if needed, so an external caller like the\n");
 	printf("                     systemd or SMF frameworks would start another copy)\n");
+	printf("                   - exit: tell the currently running driver instance to just exit\n");
+	printf("                     (so an external caller like the new driver instance, or the\n");
+	printf("                     systemd or SMF frameworks would start another copy)\n");
 	/* NOTE for FIXME above: PID-signalling is non-WIN32-only for us */
 	printf("  -P <pid>       - send the signal above to specified PID (bypassing PID file)\n");
 # endif	/* WIN32 */
@@ -264,7 +276,9 @@ void dparam_setinfo(const char *var, const char *val)
 {
 	char	vtmp[SMALLBUF];
 
-	/* store these in dstate for debugging and other help */
+	/* store these in dstate for debugging and other help
+	 * note these are not immutable since we can reload
+	 */
 	if (val) {
 		snprintf(vtmp, sizeof(vtmp), "driver.parameter.%s", var);
 		dstate_setinfo(vtmp, "%s", val);
@@ -299,6 +313,10 @@ void storeval(const char *var, char *val)
 		/* NOTE: No regard for VAR_SENSITIVE here */
 		dstate_setinfo(var+9, "%s", val);
 		dstate_setflags(var+9, ST_FLAG_IMMUTABLE);
+
+		/* note these are not immutable since we can reload
+		 * although the effect of this is questionable (FIXME)
+		 */
 		dparam_setinfo(var, val);
 		return;
 	}
@@ -364,6 +382,11 @@ void storeval(const char *var, char *val)
 		||  !strcmp(var, "device")
 		||  !strcmp(var, "busport")
 		||  !strcmp(var, "usb_set_altinterface")
+		||  !strcmp(var, "usb_config_index")
+		||  !strcmp(var, "usb_hid_rep_index")
+		||  !strcmp(var, "usb_hid_desc_index")
+		||  !strcmp(var, "usb_hid_ep_in")
+		||  !strcmp(var, "usb_hid_ep_out")
 		||  !strcmp(var, "allow_duplicates")
 		||  !strcmp(var, "langid_fix")
 		||  !strcmp(var, "noscanlangid")
@@ -532,6 +555,9 @@ int testvar_reloadable(const char *var, const char *val, int vartype)
 
 		case  0:	/* value may not be (re-)applied, but it may not have been required */
 			break;
+
+		default:
+			break;
 	}
 
 	upsdebugx(6, "%s: verdict for (re)loading var=%s value: %d",
@@ -625,6 +651,9 @@ int testval_reloadable(const char *var, const char *oldval, const char *newval,
 
 		case  0:	/* value may not be (re-)applied, but it may not have been required */
 			break;
+
+		default:
+			break;
 	}
 
 	upsdebugx(6, "%s: verdict for (re)loading var=%s value: %d",
@@ -741,6 +770,11 @@ int main_instcmd(const char *cmdname, const char *extra, conn_t *conn) {
 		}
 	}
 
+	if (!strcmp(cmdname, "driver.exit")) {
+		set_reload_flag(SIGCMD_EXIT);
+		return STAT_INSTCMD_HANDLED;
+	}
+
 #ifndef WIN32
 /* TODO: Equivalent for WIN32 - see SIGCMD_RELOAD in upd and upsmon */
 	if (!strcmp(cmdname, "driver.reload")) {
@@ -1544,6 +1578,15 @@ static void set_reload_flag(
 			break;
 #endif
 
+		case SIGCMD_EXIT:	/* Not even a signal, but a socket protocol action,
+			* and not a reload either - just applied here for consistency */
+/*
+			reload_flag = 15;
+			break;
+*/
+			set_exit_flag(-2);
+			return;
+
 		case SIGCMD_RELOAD:	/* SIGHUP */
 		case SIGCMD_RELOAD_OR_ERROR:	/* Not even a signal, but a socket protocol action */
 		default:
@@ -1557,10 +1600,13 @@ static void set_reload_flag(
 	if (sig && !strcmp(sig, SIGCMD_RELOAD_OR_ERROR)) {
 		/* reload what we can, log what needs a restart so skipped */
 		reload_flag = 1;
+	} else if (sig && !strcmp(sig, SIGCMD_EXIT)) {
+		set_exit_flag(-2);
+		return;
 	} else {
 		/* non-fatal reload as a fallback */
 		reload_flag = 1;
-        }
+	}
 
 	upsdebugx(1, "%s: raising reload flag due to command %s => reload_flag=%d",
 		__func__, sig, reload_flag);
@@ -1658,6 +1704,11 @@ int main(int argc, char **argv)
 				nut_debug_level++;
 				nut_debug_level_args++;
 				break;
+			case 'd':
+				dump_data = atoi(optarg);
+				break;
+			default:
+				break;
 		}
 	}
 	/* Reset the index, read argv[1] next time (loop below)
@@ -1730,7 +1781,9 @@ int main(int argc, char **argv)
 
 	open_syslog(progname);
 
-	upsdrv_banner();
+	if (!banner_is_disabled()) {
+		upsdrv_banner();
+	}
 
 	if (upsdrv_info.status == DRV_EXPERIMENTAL) {
 		printf("Warning: This is an experimental driver.\n");
@@ -1778,7 +1831,7 @@ int main(int argc, char **argv)
 				/* Processed above */
 				break;
 			case 'd':
-				dump_data = atoi(optarg);
+				/* Processed above */
 				break;
 			case 'i': { /* scope */
 					int ipv = atoi(optarg);
@@ -1806,6 +1859,10 @@ int main(int argc, char **argv)
 				if (!strncmp(optarg, "reload-or-error", strlen(optarg))) {
 					cmd = SIGCMD_RELOAD_OR_ERROR;
 				}
+				else
+				if (!strncmp(optarg, "exit", strlen(optarg))) {
+					cmd = SIGCMD_EXIT;
+				}
 #ifndef WIN32
 				else
 				if (!strncmp(optarg, "reload", strlen(optarg))) {
@@ -1828,9 +1885,14 @@ int main(int argc, char **argv)
 						"Error: unknown argument to option -%c. Try -h for help.", i);
 				}
 #ifndef WIN32
-				upsdebugx(1, "Will send signal %d (%s) for command '%s' "
-					"to already-running driver %s-%s (if any) and exit",
-					cmd, strsignal(cmd), optarg, progname, upsname);
+				if (cmd > 0)
+					upsdebugx(1, "Will send signal %d (%s) for command '%s' "
+						"to already-running driver %s-%s (if any) and exit",
+						cmd, strsignal(cmd), optarg, progname, upsname);
+				else
+					upsdebugx(1, "Will send request for command '%s' (internal code %d) "
+						"to already-running driver %s-%s (if any) and exit",
+						optarg, cmd, progname, upsname);
 #else
 				upsdebugx(1, "Will send request '%s' for command '%s' "
 					"to already-running driver %s-%s (if any) and exit",
@@ -1887,7 +1949,20 @@ int main(int argc, char **argv)
 				group_from_cmdline = 1;
 				break;
 			case 'V':
-				/* already printed the banner for program name */
+				/* Avoid the verbose message about
+				 * driver daemon state integration
+				 * with a service management framework
+				 * like systemd, as not too relevant
+				 * to program version reporting here
+				 * (only seen with non-zero debug) */
+				setenv("NUT_QUIET_INIT_UPSNOTIFY", "yes", 0);
+
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				if (banner_is_disabled()) {
+					/* Was not printed at start of main() */
+					upsdrv_banner();
+				}
 				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
 			case 'x':
@@ -1898,7 +1973,8 @@ int main(int argc, char **argv)
 				exit(EXIT_SUCCESS);
 			default:
 				fatalx(EXIT_FAILURE,
-					"Error: unknown option -%c. Try -h for help.", i);
+					"Error: unknown option -%c. Try -h for help.",
+					(char)i);
 		}
 	}
 
@@ -2001,40 +2077,181 @@ int main(int argc, char **argv)
 	/* Handle reload-or-error over socket protocol with
 	 * the running older driver instance */
 #ifndef WIN32
-	if (cmd == SIGCMD_RELOAD_OR_ERROR)
+	if (cmd == SIGCMD_RELOAD_OR_ERROR || cmd == SIGCMD_EXIT)
 #else
-	if (cmd && !strcmp(cmd, SIGCMD_RELOAD_OR_ERROR))
+	if (cmd && (!strcmp(cmd, SIGCMD_RELOAD_OR_ERROR) || !strcmp(cmd, SIGCMD_EXIT)))
 #endif  /* WIN32 */
 	{	/* Not a signal, but a socket protocol action */
 		ssize_t	cmdret = -1;
-		char	buf[LARGEBUF];
+		char	buf[LARGEBUF], cmdbuf[LARGEBUF];
 		struct timeval	tv;
+		char *cmdname = NULL;
+
+#ifndef WIN32
+		if (cmd == SIGCMD_RELOAD_OR_ERROR)
+#else
+		if (!strcmp(cmd, SIGCMD_RELOAD_OR_ERROR))
+#endif
+			cmdname = "reload-or-error";
+		else
+#ifndef WIN32
+		if (cmd == SIGCMD_EXIT)
+#else
+		if (!strcmp(cmd, SIGCMD_EXIT))
+#endif
+			cmdname = "exit";
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_FORMAT_OVERFLOW || defined HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_TRUNCATION)
+# pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_FORMAT_OVERFLOW
+#  pragma GCC diagnostic ignored "-Wformat-overflow"
+# endif
+# ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_TRUNCATION
+#  pragma GCC diagnostic ignored "-Wformat-truncation"
+# endif
+#endif
+		/* Some compilers do detect a chance of cmdname=NULL with
+		 * NUT builds on systems where libc does not care and prints
+		 * the right thing anyway (so NUT_STRARG macro is trivial).
+		 * In this weird case gotta silence the static checks.
+		 */
+		upsdebugx(1, "Signalling UPS [%s]: driver.%s",
+			upsname, NUT_STRARG(cmdname));
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_FORMAT_OVERFLOW || defined HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_TRUNCATION)
+# pragma GCC diagnostic pop
+#endif
+
+		if (!cmdname)
+			fatalx(EXIT_FAILURE, "Command not recognized");
 
 		/* Post the query and wait for reply */
 		/* FIXME: coordinate with pollfreq? */
 		tv.tv_sec = 15;
 		tv.tv_usec = 0;
+		snprintf(cmdbuf, sizeof(cmdbuf), "INSTCMD driver.%s\n", cmdname);
 		cmdret = upsdrvquery_oneshot(progname, upsname,
-			"INSTCMD driver.reload-or-error\n",
-			buf, sizeof(buf), &tv);
+			cmdbuf, buf, sizeof(buf), &tv);
 
 		if (cmdret < 0) {
 			upslog_with_errno(LOG_ERR, "Socket dialog with the other driver instance");
 		} else {
 			/* TODO: handle buf reply contents */
-			upslogx(LOG_INFO, "Request to reload-or-error returned code %" PRIiSIZE, cmdret);
+			upslogx(LOG_INFO, "Request for driver to %s returned code %" PRIiSIZE,
+				cmdname, cmdret);
 		}
 
 		/* exit((cmdret == 0) ? EXIT_SUCCESS : EXIT_FAILURE); */
 		exit(((cmdret < 0) || (((uintmax_t)cmdret) > ((uintmax_t)INT_MAX))) ? 255 : (int)cmdret);
 	}
 
+	/* If we would be starting as a driver (not to command a sibling),
+	 * any earlier instances should be turned off - to release access
+	 * to hardware connections and to generally avoid any confusion.
+	 * Further below we would try to use a PID file (if at all used
+	 * and still present) to terminate an earlier instance, but first
+	 * we would try to use the Unix socket protocol to tell that
+	 * earlier instance to exit cleanly. After all, this socket file
+	 * should exist for the driver to talk to the NUT data server...
+	 */
+
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
+
+	if (!cmd && (!do_forceshutdown)) {
+		ssize_t	cmdret = -1;
+		char	buf[LARGEBUF];
+		struct timeval	tv;
+
+		upsdebugx(1, "Signalling UPS [%s]: driver.exit (quietly, no fuss if no driver is running or responding)", upsname);
+
+		/* Post the query and wait for reply */
+		/* FIXME: coordinate with pollfreq? */
+		tv.tv_sec = 15;
+		tv.tv_usec = 0;
+
+		/* Hush the messages about initial connection failure, but
+		 * let "real errors" from started communication be seen.
+		 * It is okay if no driver instance is running at this
+		 * point, but if it is running but not communicating -
+		 * that is another story.
+		 */
+		nut_upsdrvquery_debug_level = NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT - 1;
+		cmdret = upsdrvquery_oneshot(progname, upsname,
+			"INSTCMD driver.exit\n",
+			buf, sizeof(buf), &tv);
+
+		upsdebugx(1, "Request for other driver to exit returned code %" PRIiSIZE,
+			cmdret);
+		if (cmdret < 0) {
+			/* Failed to communicate, assume no other instance runs */
+			upsdebug_with_errno(1, "Socket dialog with the other driver instance "
+				"(may be absent) failed");
+		} else {
+			/* NOTE: Successful dialog does not mean the other
+			 * driver instance has stopped (just that it responded
+			 * "yes, sir!" - actual wind-down can take some time.
+			 */
+			upslogx(LOG_WARNING, "Duplicate driver instance detected (local %s exists)! "
+				"Asked the other driver nicely to self-terminate!",
+#ifndef WIN32
+				"Unix socket"
+#else
+				"pipe"
+#endif
+				);
+
+			for (i = 10; i > 0; i--) {
+				if (exit_flag)
+					fatalx(EXIT_FAILURE, "Got a break signal ourselves during attempt to terminate other driver");
+
+				/* Allow driver some time to quit, and
+				 * retry until it does not respond anymore */
+				sleep(5);
+
+				if (exit_flag)
+					fatalx(EXIT_FAILURE, "Got a break signal ourselves during attempt to terminate other driver");
+
+				tv.tv_sec = 3;
+				tv.tv_usec = 0;
+				cmdret = upsdrvquery_oneshot(progname, upsname,
+					"INSTCMD driver.exit\n",
+					buf, sizeof(buf), &tv);
+				upsdebugx(1, "Subsequent request for other driver to exit returned code %"
+					PRIiSIZE, cmdret);
+
+				if (cmdret < 0)
+					break;
+			}
+
+			if (i < 1) {
+				upslogx(LOG_WARNING, "Duplicate driver instance did not respond to termination requests! "
+					"Is it stuck or from an older NUT release? "
+					"Will retry via PID file and signals, if available.");
+				/* NOTE: We would try via PID in any case,
+				 * but as we report a fault here - let the
+				 * user know that not all is lost right now :)
+				 */
+
+				/* Restore the signal errors verbosity, so that
+				 * e.g. follow-up fopen() issues can be seen -
+				 * we did probably encounter a sibling driver
+				 * instance after all, so can talk about it.
+				 */
+				nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
+			}
+		}
+
+		/* Restore the socket protocol errors verbosity */
+		nut_upsdrvquery_debug_level = NUT_UPSDRVQUERY_DEBUG_LEVEL_DEFAULT;
+	}
+
 #ifndef WIN32
 	/* Setup PID file to receive signals to communicate with this driver
-	 * instance once backgrounded, and to stop a competing older instance.
-	 * Or to send it a signal deliberately.
+	 * instance once backgrounded (or staying foregrounded with `-FF`),
+	 * and to stop a competing older instance. Or to send it a signal
+	 * deliberately.
 	 */
-	if (cmd || ((foreground == 0) && (!do_forceshutdown))) {
+	if (cmd || ((foreground == 0 || foreground == 2) && (!do_forceshutdown))) {
 		char	pidfnbuf[SMALLBUF];
 
 		snprintf(pidfnbuf, sizeof(pidfnbuf), "%s/%s-%s.pid", altpidpath(), progname, upsname);
@@ -2043,9 +2260,9 @@ int main(int argc, char **argv)
 			int cmdret = -1;
 			/* Send a signal to older copy of the driver, if any */
 			if (oldpid < 0) {
-				cmdret = sendsignalfn(pidfnbuf, cmd);
+				cmdret = sendsignalfn(pidfnbuf, cmd, progname, 1);
 			} else {
-				cmdret = sendsignalpid(oldpid, cmd);
+				cmdret = sendsignalpid(oldpid, cmd, progname, 1);
 			}
 
 			switch (cmdret) {
@@ -2061,7 +2278,7 @@ int main(int argc, char **argv)
 				 */
 				upslogx(LOG_WARNING, "Could not %s PID file '%s' "
 					"to see if previous driver instance is "
-					"already running!",
+					"already running or not!",
 					(cmdret == -3 ? "find" : "parse"),
 					pidfnbuf);
 				break;
@@ -2072,21 +2289,21 @@ int main(int argc, char **argv)
 				/* if cmd was nontrivial - speak up below, else be quiet */
 				upsdebugx(1, "Just failed to send signal, no daemon was running");
 				break;
-			}
+			} /* switch (cmdret) */
 
-		/* We were signalling a daemon, successfully or not - exit now...
-		 * Modulo the possibility of a "reload-or-something" where we
-		 * effectively terminate the old driver and start a new one due
-		 * to configuration changes that were not reloadable. Such mode
-		 * is not implemented currently.
-		 */
-		if (cmdret != 0) {
-			/* sendsignal*() above might have logged more details
-			 * for troubleshooting, e.g. about lack of PID file
+			/* We were signalling a daemon, successfully or not - exit now...
+			 * Modulo the possibility of a "reload-or-something" where we
+			 * effectively terminate the old driver and start a new one due
+			 * to configuration changes that were not reloadable. Such mode
+			 * is not implemented currently.
 			 */
-			upslogx(LOG_NOTICE, "Failed to signal the currently running daemon (if any)");
+			if (cmdret != 0) {
+				/* sendsignal*() above might have logged more details
+				 * for troubleshooting, e.g. about lack of PID file
+				 */
+				upslogx(LOG_NOTICE, "Failed to signal the currently running daemon (if any)");
 # ifdef HAVE_SYSTEMD
-			switch (cmd) {
+				switch (cmd) {
 				case SIGCMD_RELOAD:
 					upslogx(LOG_NOTICE, "Try something like "
 						"'systemctl reload nut-driver@%s.service'%s",
@@ -2111,7 +2328,7 @@ int main(int argc, char **argv)
 						upsname,
 						(oldpid < 0 ? " or add '-P $PID' argument" : ""));
 					break;
-				}
+				} /* switch (cmd) */
 				/* ... or edit nut-server.service locally to start `upsd -FF`
 				 * and so save the PID file for ability to manage the daemon
 				 * beside the service framework, possibly confusing things...
@@ -2121,40 +2338,47 @@ int main(int argc, char **argv)
 					upslogx(LOG_NOTICE, "Try to add '-P $PID' argument");
 				}
 # endif	/* HAVE_SYSTEMD */
-			}
+			} /* if (cmdret != 0) */
 
 			exit((cmdret == 0) ? EXIT_SUCCESS : EXIT_FAILURE);
-		}
+		} /* if (cmd) */
 
 		/* Try to prevent that driver is started multiple times. If a PID file */
 		/* already exists, send a TERM signal to the process and try if it goes */
 		/* away. If not, retry a couple of times. */
 		for (i = 0; i < 3; i++) {
 			struct stat	st;
+			int	sigret;
 
-			if (stat(pidfnbuf, &st) != 0) {
-				/* PID file not found */
+			if ((sigret = stat(pidfnbuf, &st)) != 0) {
+				upsdebugx(1, "PID file %s not found; stat() returned %d (errno=%d): %s",
+					pidfnbuf, sigret, errno, strerror(errno));
 				break;
 			}
 
 			upslogx(LOG_WARNING, "Duplicate driver instance detected (PID file %s exists)! Terminating other driver!", pidfnbuf);
 
-			if (sendsignalfn(pidfnbuf, SIGTERM) != 0) {
-				/* Can't send signal to PID, assume invalid file */
+			if ((sigret = sendsignalfn(pidfnbuf, SIGTERM, progname, 1) != 0)) {
+				upsdebugx(1, "Can't send signal to PID, assume invalid PID file %s; "
+					"sendsignalfn() returned %d (errno=%d): %s",
+					pidfnbuf, sigret, errno, strerror(errno));
 				break;
 			}
 
-			/* Allow driver some time to quit */
+			upsdebugx(1, "Signal sent without errors, allow the other driver instance some time to quit");
 			sleep(5);
+
+			if (exit_flag)
+				fatalx(EXIT_FAILURE, "Got a break signal during attempt to terminate other driver");
 		}
 
 		if (i > 0) {
 			struct stat	st;
 			if (stat(pidfnbuf, &st) == 0) {
 				upslogx(LOG_WARNING, "Duplicate driver instance is still alive (PID file %s exists) after several termination attempts! Killing other driver!", pidfnbuf);
-				if (sendsignalfn(pidfnbuf, SIGKILL) == 0) {
+				if (sendsignalfn(pidfnbuf, SIGKILL, progname, 1) == 0) {
 					sleep(5);
-					if (sendsignalfn(pidfnbuf, 0) == 0) {
+					if (sendsignalfn(pidfnbuf, 0, progname, 1) == 0) {
 						upslogx(LOG_WARNING, "Duplicate driver instance is still alive (could signal the process)");
 						/* TODO: Should we writepid() below in this case?
 						 * Or if driver init fails, restore the old content
@@ -2198,7 +2422,7 @@ int main(int argc, char **argv)
 		upslogx(LOG_WARNING, "Duplicate driver instance detected! Terminating other driver!");
 		for(i=0;i<10;i++) {
 			DWORD res;
-			sendsignal(name, COMMAND_STOP);
+			sendsignal(name, COMMAND_STOP, 1);
 			if(mutex != NULL ) {
 				res = WaitForSingleObject(mutex,1000);
 				if(res==WAIT_OBJECT_0) {
@@ -2219,6 +2443,9 @@ int main(int argc, char **argv)
 	}
 #endif	/* WIN32 */
 
+	/* Restore the signal errors verbosity */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
+
 	/* clear out callback handler data */
 	memset(&upsh, '\0', sizeof(upsh));
 
@@ -2445,6 +2672,7 @@ int main(int argc, char **argv)
 				snprintf(pidfnbuf, sizeof(pidfnbuf), "%s/%s-%s.pid", altpidpath(), progname, upsname);
 				pidfn = xstrdup(pidfnbuf);
 			}
+			/* Probably was saved above already, but better safe than sorry */
 			upslogx(LOG_WARNING, "Running as foreground process, but saving a PID file anyway");
 			writepid(pidfn);
 			break;
@@ -2453,7 +2681,10 @@ int main(int argc, char **argv)
 			upslogx(LOG_WARNING, "Running as foreground process, not saving a PID file");
 	}
 
-	dstate_setinfo("driver.flag.allow_killpower", "0");
+	/* May already be set by parsed configuration flag, only set default if not: */
+	if (dstate_getinfo("driver.flag.allow_killpower") == NULL)
+		dstate_setinfo("driver.flag.allow_killpower", "0");
+
 	dstate_setflags("driver.flag.allow_killpower", ST_FLAG_RW | ST_FLAG_NUMBER);
 	dstate_addcmd("driver.killpower");
 
diff --git a/drivers/main.h b/drivers/main.h
index 1658ae3491..5276c98ece 100644
--- a/drivers/main.h
+++ b/drivers/main.h
@@ -1,5 +1,5 @@
 #ifndef NUT_MAIN_H_SEEN
-#define NUT_MAIN_H_SEEN
+#define NUT_MAIN_H_SEEN 1
 
 #include "common.h"
 #include "upsconf.h"
@@ -131,6 +131,7 @@ void setup_signals(void);
 #ifndef WIN32
 # define SIGCMD_RELOAD                  SIGHUP
 /* not a signal, so negative; relies on socket protocol */
+# define SIGCMD_EXIT                    -SIGTERM
 # define SIGCMD_RELOAD_OR_ERROR         -SIGCMD_RELOAD
 # define SIGCMD_RELOAD_OR_EXIT          SIGUSR1
 /* // FIXME: Implement this self-recycling in drivers (keeping the PID):
@@ -153,6 +154,7 @@ void setup_signals(void);
 # endif
 #else
 /* FIXME: handle WIN32 builds for other signals too */
+# define SIGCMD_EXIT                    "driver.exit"
 # define SIGCMD_RELOAD_OR_ERROR         "driver.reload-or-error"
 #endif	/* WIN32 */
 
diff --git a/drivers/masterguard.c b/drivers/masterguard.c
index 37cae77651..f5bbb397ce 100644
--- a/drivers/masterguard.c
+++ b/drivers/masterguard.c
@@ -29,7 +29,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"MASTERGUARD UPS driver"
-#define DRIVER_VERSION	"0.26"
+#define DRIVER_VERSION	"0.27"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -164,7 +164,7 @@ static void parseFlags( char *flags )
  ********************************************************************/
 static void query1( char *buf )
 {
-	#define WORDMAXLEN 255
+#	define WORDMAXLEN 255
 	char    value[WORDMAXLEN];
 	char    word[WORDMAXLEN];
 	char    *newPOS;
@@ -238,7 +238,7 @@ static void query1( char *buf )
  ********************************************************************/
 static void query3( char *buf )
 {
-	#define WORDMAXLEN 255
+#	define WORDMAXLEN 255
 	char    value[WORDMAXLEN];
 	char    word[WORDMAXLEN];
 	char    *newPOS;
diff --git a/drivers/metasys.c b/drivers/metasys.c
index e5003b116f..cae06a174b 100644
--- a/drivers/metasys.c
+++ b/drivers/metasys.c
@@ -28,7 +28,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Metasystem UPS driver"
-#define DRIVER_VERSION	"0.09"
+#define DRIVER_VERSION	"0.10"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/mge-hid.c b/drivers/mge-hid.c
index 81c3a1298b..b174ac4d6b 100644
--- a/drivers/mge-hid.c
+++ b/drivers/mge-hid.c
@@ -2,7 +2,7 @@
  *
  *  Copyright (C)
  *        2003 - 2015 Arnaud Quette <arnaud.quette@free.fr>
- *        2015 - 2016 Eaton / Arnaud Quette <ArnaudQuette@Eaton.com>
+ *        2015 - 2024 Eaton / Arnaud Quette <ArnaudQuette@Eaton.com>
  *
  *  Sponsored by MGE UPS SYSTEMS <http://www.mgeups.com>
  *
@@ -50,7 +50,7 @@
 # endif
 #endif
 
-#define MGE_HID_VERSION		"MGE HID 1.46"
+#define MGE_HID_VERSION		"MGE HID 1.48"
 
 /* (prev. MGE Office Protection Systems, prev. MGE UPS SYSTEMS) */
 /* Eaton */
@@ -63,18 +63,18 @@
 #define POWERWARE_VENDORID	0x0592
 
 /* Hewlett Packard */
-#define HP_VENDORID 0x03f0
+#define HP_VENDORID		0x03f0
 
 /* AEG */
-#define AEG_VENDORID 0x2b2d
+#define AEG_VENDORID		0x2b2d
 
 /* Note that normally this VID is handled by Liebert/Phoenixtec HID mapping,
  * here it is just for for AEG PROTECT NAS devices: */
 /* Phoenixtec Power Co., Ltd */
-#define PHOENIXTEC 0x06da
+#define PHOENIXTEC		0x06da
 
 /* IBM */
-#define IBM_VENDORID 0x04b3
+#define IBM_VENDORID		0x04b3
 
 #if !((defined SHUT_MODE) && SHUT_MODE)
 #include "usb-common.h"
@@ -131,7 +131,8 @@ typedef enum {
 		MGE_PULSAR_M_2200,
 		MGE_PULSAR_M_3000,
 		MGE_PULSAR_M_3000_XL,
-	EATON_5P = 0x500			/* Eaton 5P / 5PX series */
+	EATON_5P = 0x500,			/* Eaton 5P / 5PX / 5SC series */
+	EATON_9E = 0x900			/* Eaton 9E entry-level series */
 } models_type_t;
 
 /* Default to line-interactive or online (ie, not offline).
@@ -207,14 +208,14 @@ static long round (double value)
 static long round (LDOUBLE value)
 # endif
 {
-  long intpart;
+	long intpart;
 
-  intpart = (long)value;
-  value = value - intpart;
-  if (value >= 0.5)
-    intpart++;
+	intpart = (long)value;
+	value = value - intpart;
+	if (value >= 0.5)
+		intpart++;
 
-  return intpart;
+	return intpart;
 }
 #endif /* HAVE_DECL_ROUND */
 
@@ -489,6 +490,7 @@ static const char *mge_battery_voltage_nominal_fun(double value)
 
 	case MGE_PULSAR_M:
 	case EATON_5P:
+	case EATON_9E:	/* Presumably per https://github.com/networkupstools/nut/issues/1925#issuecomment-1562342854 */
 		break;
 
 	default:
@@ -514,6 +516,7 @@ static const char *mge_battery_voltage_fun(double value)
 	case MGE_EVOLUTION:
 	case MGE_PULSAR_M:
 	case EATON_5P:
+	case EATON_9E:	/* Presumably per https://github.com/networkupstools/nut/issues/1925#issuecomment-1562342854 */
 		break;
 
 	default:
@@ -1123,6 +1126,55 @@ static models_name_t mge_model_names [] =
 	{ "Eaton 5P", "1150", EATON_5P, "5P 1150" },
 	{ "Eaton 5P", "1550", EATON_5P, "5P 1550" },
 
+	/* Eaton 5PX, names assumed per VA numbers in
+	 * https://www.eaton.com/gb/en-gb/catalog/backup-power-ups-surge-it-power-distribution/eaton-5px-ups-emea.html#tab-2
+	 * and a user report in https://github.com/networkupstools/nut/issues/2380
+	 * Fixes for actual product/model names reported via USB are welcome
+	 */
+	{ "Eaton 5PX", "1500", EATON_5P, NULL },
+	{ "Eaton 5PX", "2200", EATON_5P, NULL },
+	{ "Eaton 5PX", "3000", EATON_5P, NULL },
+
+	/* Eaton 5SC, names assumed per VA numbers in
+	 * https://www.eaton.com/gb/en-gb/site-search.html.searchTerm$5sc.tabs$all.html
+	 * and a user report in https://github.com/networkupstools/nut/issues/2380
+	 * Fixes for actual product/model names reported via USB are welcome
+	 */
+	{ "Eaton 5SC", "500", EATON_5P, NULL },
+	{ "Eaton 5SC", "750", EATON_5P, NULL },
+	{ "Eaton 5SC", "1000", EATON_5P, NULL },
+	{ "Eaton 5SC", "1500", EATON_5P, NULL },
+	{ "Eaton 5SC", "2200", EATON_5P, NULL },
+	{ "Eaton 5SC", "3000", EATON_5P, NULL },
+
+	/* Eaton 9E entry-level series per discussions in
+	 * https://github.com/networkupstools/nut/issues/1925
+	 * https://github.com/networkupstools/nut/issues/2380
+	 * https://github.com/networkupstools/nut/issues/2492
+	 */
+	{ "Eaton 9E", "1000",  EATON_9E, "9E1000" },
+	{ "Eaton 9E", "1000i", EATON_9E, "9E1000i" },
+	{ "Eaton 9E", "1000iau", EATON_9E, "9E1000iau" },
+	{ "Eaton 9E", "1000ir", EATON_9E, "9E1000ir" },
+	{ "Eaton 9E", "2000",  EATON_9E, "9E2000" },
+	{ "Eaton 9E", "2000i", EATON_9E, "9E2000i" },
+	{ "Eaton 9E", "2000iau", EATON_9E, "9E2000iau" },
+	{ "Eaton 9E", "2000ir", EATON_9E, "9E2000ir" },
+	{ "Eaton 9E", "3000",  EATON_9E, "9E3000" },
+	{ "Eaton 9E", "3000i", EATON_9E, "9E3000i" },
+	{ "Eaton 9E", "3000iau", EATON_9E, "9E3000iau" },
+	{ "Eaton 9E", "3000ir", EATON_9E, "9E3000ir" },
+	{ "Eaton 9E", "3000ixl", EATON_9E, "9E3000ixl" },
+	{ "Eaton 9E", "3000ixlau", EATON_9E, "9E3000ixlau" },
+
+	/* https://github.com/networkupstools/nut/issues/1925#issuecomment-1609262963
+	 * if we failed to get iManufacturer, iProduct and iSerialNumber but saw
+	 * the UPS.Flow.[4].ConfigApparentPower (the "2000" or "3000" part here)
+	 */
+	{ "unknown",  "1000",  EATON_9E, "9E1000i (presumed)" },
+	{ "unknown",  "2000",  EATON_9E, "9E2000i (presumed)" },
+	{ "unknown",  "3000",  EATON_9E, "9E3000i (presumed)" },
+
 	/* Pulsar M models */
 	{ "PULSAR M", "2200", MGE_PULSAR_M_2200, NULL },
 	{ "PULSAR M", "3000", MGE_PULSAR_M_3000, NULL },
@@ -1648,6 +1700,9 @@ static int mge_claim(HIDDevice_t *hd) {
 
 				/* Let liebert-hid grab this */
 				return 0;
+
+			default:
+				break;
 		}
 
 		return 1;
diff --git a/drivers/mge-utalk.c b/drivers/mge-utalk.c
index 9e34954199..dca2a14fe6 100644
--- a/drivers/mge-utalk.c
+++ b/drivers/mge-utalk.c
@@ -69,7 +69,7 @@
 /* --------------------------------------------------------------- */
 
 #define DRIVER_NAME	"MGE UPS SYSTEMS/U-Talk driver"
-#define DRIVER_VERSION	"0.95"
+#define DRIVER_VERSION	"0.96"
 
 
 /* driver description structure */
diff --git a/drivers/mge-utalk.h b/drivers/mge-utalk.h
index 67b1135533..91efb054f1 100644
--- a/drivers/mge-utalk.h
+++ b/drivers/mge-utalk.h
@@ -173,10 +173,10 @@ static const double multiplier[4][8] = {
 
 /* use explicit booleans */
 #ifdef FALSE
-	#undef FALSE
+#	undef FALSE
 #endif /* FALSE */
 #ifdef TRUE
-	#undef TRUE
+#	undef TRUE
 #endif /* TRUE */
 typedef enum ebool { FALSE=0, TRUE } bool_t;
 
diff --git a/drivers/mge-xml.c b/drivers/mge-xml.c
index 42eab857c7..b7ec2c59c0 100644
--- a/drivers/mge-xml.c
+++ b/drivers/mge-xml.c
@@ -510,6 +510,8 @@ static const char *mge_beeper_info(const char *arg_val)
 		return "enabled";
 	case 3:
 		return "muted";
+	default:
+		break;
 	}
 	return NULL;
 }
@@ -528,6 +530,8 @@ static const char *mge_upstype_conversion(const char *arg_val)
 		return "online - parallel with hot standy";
 	case 5:
 		return "online - hot standby redundancy";
+	default:
+		break;
 	}
 	return NULL;
 }
@@ -542,6 +546,8 @@ static const char *mge_sensitivity_info(const char *arg_val)
 		return "high";
 	case 2:
 		return "low";
+	default:
+		break;
 	}
 	return NULL;
 }
@@ -566,6 +572,8 @@ static const char *mge_test_result_info(const char *arg_val)
 		return "no test initiated";
 	case 7:
 		return "test scheduled";
+	default:
+		break;
 	}
 	return NULL;
 }
@@ -1416,6 +1424,10 @@ static int mge_xml_startelm_cb(void *userdata, int parent, const char *nspace, c
 			state = XC_BROADCAST;
 			break;
 		}
+		break;
+
+	default:
+		break;
 	}
 
 	upsdebugx(3, "%s: name <%s> (parent = %d, state = %d)", __func__, name, parent, state);
@@ -1445,6 +1457,9 @@ static int mge_xml_cdata_cb(void *userdata, int state, const char *cdata, size_t
 	case GO_OBJECT:
 		snprintfcat(val, sizeof(val), "%.*s", (int)len, cdata);
 		break;
+
+	default:
+		break;
 	}
 
 	return 0;
@@ -1517,6 +1532,9 @@ static int mge_xml_endelm_cb(void *userdata, int state, const char *nspace, cons
 			&inited_phaseinfo_out, &num_outphases, 0);
 
 		break;
+
+	default:
+		break;
 	}
 
 	return 0;
diff --git a/drivers/microdowell.c b/drivers/microdowell.c
index 9b2637ea81..0d491b1c7e 100644
--- a/drivers/microdowell.c
+++ b/drivers/microdowell.c
@@ -44,7 +44,7 @@
 #define MAX_SHUTDOWN_DELAY_LEN 5
 
 #define DRIVER_NAME	"MICRODOWELL UPS driver"
-#define DRIVER_VERSION	"0.03"
+#define DRIVER_VERSION	"0.04"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -213,7 +213,7 @@ static void SendCmdToSerial(unsigned char *Buff, size_t Len)
 
 static unsigned char * CmdSerial(unsigned char *OutBuffer, size_t Len, unsigned char *RetBuffer)
 {
-	#define TMP_BUFF_LEN	1024
+#	define TMP_BUFF_LEN	1024
 	unsigned char InpBuff[TMP_BUFF_LEN+1] ;
 	unsigned char TmpBuff[3] ;
 	int i, ErrCode ;
diff --git a/drivers/microsol-apc.c b/drivers/microsol-apc.c
index 329263703f..c8979b67b1 100644
--- a/drivers/microsol-apc.c
+++ b/drivers/microsol-apc.c
@@ -35,7 +35,7 @@
 #include "microsol-apc.h"
 
 #define DRIVER_NAME	"APC Back-UPS BR series UPS driver"
-#define DRIVER_VERSION	"0.70"
+#define DRIVER_VERSION	"0.71"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/netxml-ups.c b/drivers/netxml-ups.c
index 7ebc30432f..cfdc31632c 100644
--- a/drivers/netxml-ups.c
+++ b/drivers/netxml-ups.c
@@ -42,7 +42,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"network XML UPS"
-#define DRIVER_VERSION	"0.45"
+#define DRIVER_VERSION	"0.46"
 
 /** *_OBJECT query multi-part body boundary */
 #define FORM_POST_BOUNDARY "NUT-NETXML-UPS-OBJECTS"
@@ -1149,13 +1149,36 @@ static void object_entry_destroy(object_query_t *handle, object_entry_t *entry)
 	switch (handle->type) {
 		case SET_OBJECT_REQUEST:
 			set_object_req_destroy(&entry->payld.req);
-
 			break;
 
 		case SET_OBJECT_RESPONSE:
 			set_object_resp_destroy(&entry->payld.resp);
+			break;
 
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
 			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
 	/* Destroy entry */
@@ -1809,13 +1832,36 @@ static object_query_t *set_object(object_query_t *req) {
 	switch (req->mode) {
 		case RAW_POST:
 			resp = set_object_raw(req);
-
 			break;
 
 		case FORM_POST:
 			resp = set_object_form(req);
+			break;
 
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
 			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
 	return resp;
diff --git a/drivers/nut-ipmipsu.c b/drivers/nut-ipmipsu.c
index 1ed5ea72ad..95845285a3 100644
--- a/drivers/nut-ipmipsu.c
+++ b/drivers/nut-ipmipsu.c
@@ -27,7 +27,7 @@
 #include "nut-ipmi.h"
 
 #define DRIVER_NAME	"IPMI PSU driver"
-#define DRIVER_VERSION	"0.32"
+#define DRIVER_VERSION	"0.33"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -183,7 +183,8 @@ void upsdrv_help(void)
 /* list flags and values that you want to receive via -x */
 void upsdrv_makevartable(void)
 {
-	/* FIXME: need more params.
+	/* FIXME: need more params. */
+/*
 	addvar(VAR_VALUE, "username", "Remote server username");
 	addvar(VAR_VALUE, "password", "Remote server password");
 	addvar(VAR_VALUE, "authtype",
@@ -192,7 +193,9 @@ void upsdrv_makevartable(void)
 		"Type of the device to match ('psu' for \"Power Supply\")");
 
 	addvar(VAR_VALUE, "serial", "Serial number to match a specific device");
-	addvar(VAR_VALUE, "fruid", "FRU identifier to match a specific device"); */
+	addvar(VAR_VALUE, "fruid", "FRU identifier to match a specific device");
+	addvar(VAR_VALUE, "sensorid", "Sensor identifier to match a specific device");
+*/
 }
 
 void upsdrv_initups(void)
diff --git a/drivers/nut-libfreeipmi.c b/drivers/nut-libfreeipmi.c
index cdf3d59fb4..02f87b090c 100644
--- a/drivers/nut-libfreeipmi.c
+++ b/drivers/nut-libfreeipmi.c
@@ -48,7 +48,7 @@
 #include <freeipmi/freeipmi.h>
 #include <ipmi_monitoring.h>
 #if HAVE_FREEIPMI_MONITORING
-#include <ipmi_monitoring_bitmasks.h>
+# include <ipmi_monitoring_bitmasks.h>
 #endif
 #include "nut-ipmi.h"
 #include "nut_stdint.h"
@@ -69,41 +69,41 @@ static ipmi_monitoring_ctx_t mon_ctx = NULL;
 #ifdef HAVE_FREEIPMI_11X_12X
   static ipmi_sdr_ctx_t sdr_ctx = NULL;
   static ipmi_fru_ctx_t fru_ctx = NULL;
-  #define SDR_PARSE_CTX sdr_ctx
-  #define NUT_IPMI_SDR_CACHE_DEFAULTS                              IPMI_SDR_CACHE_CREATE_FLAGS_DEFAULT
+#  define SDR_PARSE_CTX sdr_ctx
+#  define NUT_IPMI_SDR_CACHE_DEFAULTS                              IPMI_SDR_CACHE_CREATE_FLAGS_DEFAULT
 #else
   static ipmi_sdr_cache_ctx_t sdr_ctx = NULL;
   static ipmi_sdr_parse_ctx_t sdr_parse_ctx = NULL;
-  #define SDR_PARSE_CTX sdr_parse_ctx
+#  define SDR_PARSE_CTX sdr_parse_ctx
   static ipmi_fru_parse_ctx_t fru_ctx = NULL;
   /* Functions remapping */
-  #define ipmi_sdr_ctx_create                           ipmi_sdr_cache_ctx_create
-  #define ipmi_sdr_ctx_destroy                          ipmi_sdr_cache_ctx_destroy
-  #define ipmi_sdr_ctx_errnum                           ipmi_sdr_cache_ctx_errnum
-  #define ipmi_sdr_ctx_errormsg                         ipmi_sdr_cache_ctx_errormsg
-  #define ipmi_fru_ctx_create                           ipmi_fru_parse_ctx_create
-  #define ipmi_fru_ctx_destroy                          ipmi_fru_parse_ctx_destroy
-  #define ipmi_fru_ctx_set_flags                        ipmi_fru_parse_ctx_set_flags
-  #define ipmi_fru_ctx_strerror                         ipmi_fru_parse_ctx_strerror
-  #define ipmi_fru_ctx_errnum                           ipmi_fru_parse_ctx_errnum
-  #define ipmi_fru_open_device_id                       ipmi_fru_parse_open_device_id
-  #define ipmi_fru_close_device_id                      ipmi_fru_parse_close_device_id
-  #define ipmi_fru_ctx_errormsg                         ipmi_fru_parse_ctx_errormsg
-  #define ipmi_fru_read_data_area                       ipmi_fru_parse_read_data_area
-  #define ipmi_fru_next                                 ipmi_fru_parse_next
-  #define ipmi_fru_type_length_field_to_string          ipmi_fru_parse_type_length_field_to_string
-  #define ipmi_fru_multirecord_power_supply_information ipmi_fru_parse_multirecord_power_supply_information
-  #define ipmi_fru_board_info_area                      ipmi_fru_parse_board_info_area
-  #define ipmi_fru_field_t                              ipmi_fru_parse_field_t
+#  define ipmi_sdr_ctx_create                           ipmi_sdr_cache_ctx_create
+#  define ipmi_sdr_ctx_destroy                          ipmi_sdr_cache_ctx_destroy
+#  define ipmi_sdr_ctx_errnum                           ipmi_sdr_cache_ctx_errnum
+#  define ipmi_sdr_ctx_errormsg                         ipmi_sdr_cache_ctx_errormsg
+#  define ipmi_fru_ctx_create                           ipmi_fru_parse_ctx_create
+#  define ipmi_fru_ctx_destroy                          ipmi_fru_parse_ctx_destroy
+#  define ipmi_fru_ctx_set_flags                        ipmi_fru_parse_ctx_set_flags
+#  define ipmi_fru_ctx_strerror                         ipmi_fru_parse_ctx_strerror
+#  define ipmi_fru_ctx_errnum                           ipmi_fru_parse_ctx_errnum
+#  define ipmi_fru_open_device_id                       ipmi_fru_parse_open_device_id
+#  define ipmi_fru_close_device_id                      ipmi_fru_parse_close_device_id
+#  define ipmi_fru_ctx_errormsg                         ipmi_fru_parse_ctx_errormsg
+#  define ipmi_fru_read_data_area                       ipmi_fru_parse_read_data_area
+#  define ipmi_fru_next                                 ipmi_fru_parse_next
+#  define ipmi_fru_type_length_field_to_string          ipmi_fru_parse_type_length_field_to_string
+#  define ipmi_fru_multirecord_power_supply_information ipmi_fru_parse_multirecord_power_supply_information
+#  define ipmi_fru_board_info_area                      ipmi_fru_parse_board_info_area
+#  define ipmi_fru_field_t                              ipmi_fru_parse_field_t
   /* Constants */
-  #define IPMI_SDR_MAX_RECORD_LENGTH                               IPMI_SDR_CACHE_MAX_SDR_RECORD_LENGTH
-  #define IPMI_SDR_ERR_CACHE_READ_CACHE_DOES_NOT_EXIST             IPMI_SDR_CACHE_ERR_CACHE_READ_CACHE_DOES_NOT_EXIST
-  #define IPMI_FRU_AREA_SIZE_MAX                                   IPMI_FRU_PARSE_AREA_SIZE_MAX
-  #define IPMI_FRU_FLAGS_SKIP_CHECKSUM_CHECKS                      IPMI_FRU_PARSE_FLAGS_SKIP_CHECKSUM_CHECKS
-  #define IPMI_FRU_AREA_TYPE_BOARD_INFO_AREA                       IPMI_FRU_PARSE_AREA_TYPE_BOARD_INFO_AREA
-  #define IPMI_FRU_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION  IPMI_FRU_PARSE_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION
-  #define IPMI_FRU_AREA_STRING_MAX                                 IPMI_FRU_PARSE_AREA_STRING_MAX
-  #define NUT_IPMI_SDR_CACHE_DEFAULTS                              IPMI_SDR_CACHE_CREATE_FLAGS_DEFAULT, IPMI_SDR_CACHE_VALIDATION_FLAGS_DEFAULT
+#  define IPMI_SDR_MAX_RECORD_LENGTH                               IPMI_SDR_CACHE_MAX_SDR_RECORD_LENGTH
+#  define IPMI_SDR_ERR_CACHE_READ_CACHE_DOES_NOT_EXIST             IPMI_SDR_CACHE_ERR_CACHE_READ_CACHE_DOES_NOT_EXIST
+#  define IPMI_FRU_AREA_SIZE_MAX                                   IPMI_FRU_PARSE_AREA_SIZE_MAX
+#  define IPMI_FRU_FLAGS_SKIP_CHECKSUM_CHECKS                      IPMI_FRU_PARSE_FLAGS_SKIP_CHECKSUM_CHECKS
+#  define IPMI_FRU_AREA_TYPE_BOARD_INFO_AREA                       IPMI_FRU_PARSE_AREA_TYPE_BOARD_INFO_AREA
+#  define IPMI_FRU_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION  IPMI_FRU_PARSE_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION
+#  define IPMI_FRU_AREA_STRING_MAX                                 IPMI_FRU_PARSE_AREA_STRING_MAX
+#  define NUT_IPMI_SDR_CACHE_DEFAULTS                              IPMI_SDR_CACHE_CREATE_FLAGS_DEFAULT, IPMI_SDR_CACHE_VALIDATION_FLAGS_DEFAULT
 #endif /* HAVE_FREEIPMI_11X_12X */
 
 /* FIXME: freeipmi auto selects a cache based on the hostname you are
@@ -310,22 +310,23 @@ static const char* libfreeipmi_getfield (uint8_t language_code,
 	if (strbuflen)
 		return strbuf;
 
-  return NULL;
+	return NULL;
 }
 
 /* Get voltage value from the IPMI voltage code */
 static float libfreeipmi_get_voltage (uint8_t voltage_code)
 {
-  if (voltage_code == IPMI_FRU_VOLTAGE_12V)
-    return 12;
-  else if (voltage_code == IPMI_FRU_VOLTAGE_MINUS12V)
-    return -12;
-  else if (voltage_code == IPMI_FRU_VOLTAGE_5V)
-    return 5;
-  else if (voltage_code == IPMI_FRU_VOLTAGE_3_3V)
-    return 3.3;
-  else
-    return 0;
+	/* FIXME: switch/case? */
+	if (voltage_code == IPMI_FRU_VOLTAGE_12V)
+		return 12;
+	else if (voltage_code == IPMI_FRU_VOLTAGE_MINUS12V)
+		return -12;
+	else if (voltage_code == IPMI_FRU_VOLTAGE_5V)
+		return 5;
+	else if (voltage_code == IPMI_FRU_VOLTAGE_3_3V)
+		return 3.3;
+	else
+		return 0;
 }
 
 /* Cleanup IPMI contexts */
@@ -363,6 +364,11 @@ static int libfreeipmi_get_psu_info (const void *areabuf,
 										uint8_t area_length,
 										IPMIDevice_t *ipmi_dev)
 {
+	/* FIXME: libfreeipmi headers currently define the 4 voltage_range
+	 * values as "unsigned int". It seems earlier it was "int", but now
+	 * the compiler complains when it is in place - so changed to unsigned.
+	 * The proper fix might be to detect and influence this in configure. */
+
 	/* FIXME: directly use ipmi_dev fields */
 	unsigned int overall_capacity;
 	input_voltage_range_t low_end_input_voltage_range_1;
@@ -1063,6 +1069,8 @@ int nut_ipmi_get_sensors_status(IPMIDevice_t *ipmi_dev)
 					str_count++;
 				}
 				break;
+			default:
+				break;
 		}
 	}
 
@@ -1086,6 +1094,8 @@ int nut_ipmi_get_sensors_status(IPMIDevice_t *ipmi_dev)
 				status_set("OFF");
 				retval = 0;
 				break;
+			default:
+				break;
 		}
 
 		status_commit();
diff --git a/drivers/nutdrv_atcl_usb.c b/drivers/nutdrv_atcl_usb.c
index c8d1162e2e..5c52057a33 100644
--- a/drivers/nutdrv_atcl_usb.c
+++ b/drivers/nutdrv_atcl_usb.c
@@ -28,7 +28,7 @@
 
 /* driver version */
 #define DRIVER_NAME	"'ATCL FOR UPS' USB driver"
-#define DRIVER_VERSION	"1.17"
+#define DRIVER_VERSION	"1.18"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -440,6 +440,9 @@ static int usb_device_open(usb_dev_handle **handlep, USBDevice_t *device, USBDev
 				case -2:
 					upsdebugx(4, "matcher: unspecified error");
 					goto next_device;
+
+				default:
+					break;
 				}
 			}
 #ifdef HAVE_LIBUSB_SET_AUTO_DETACH_KERNEL_DRIVER
@@ -686,6 +689,7 @@ void upsdrv_makevartable(void)
 {
 	/* NOTE: This driver uses a very custom device matching method,
 	 * so does not involve nut_usb_addvars() method like others do.
+	 * When fixing, see also tools/nut-scanner/scan_usb.c "exceptions".
 	 */
 	addvar(VAR_VALUE, "vendor", "USB vendor string (or NULL if none)");
 }
diff --git a/drivers/nutdrv_qx.c b/drivers/nutdrv_qx.c
index 177a659d22..3bc1d8675a 100644
--- a/drivers/nutdrv_qx.c
+++ b/drivers/nutdrv_qx.c
@@ -47,22 +47,22 @@
 
 /* note: QX_USB/QX_SERIAL set through Makefile */
 #ifdef QX_USB
-	#include "nut_libusb.h" /* also includes "usb-common.h" */
+#	include "nut_libusb.h" /* also includes "usb-common.h" */
 
-	#ifdef QX_SERIAL
-		#define DRIVER_NAME	"Generic Q* USB/Serial driver"
-	#else
-		#define	DRIVER_NAME	"Generic Q* USB driver"
-	#endif	/* QX_SERIAL */
+#	ifdef QX_SERIAL
+#		define DRIVER_NAME	"Generic Q* USB/Serial driver"
+#	else
+#		define	DRIVER_NAME	"Generic Q* USB driver"
+#	endif	/* QX_SERIAL */
 #else
-	#define DRIVER_NAME	"Generic Q* Serial driver"
+#	define DRIVER_NAME	"Generic Q* Serial driver"
 #endif	/* QX_USB */
 
-#define DRIVER_VERSION	"0.36"
+#define DRIVER_VERSION	"0.37"
 
 #ifdef QX_SERIAL
-	#include "serial.h"
-	#define SER_WAIT_SEC	1	/* 3 seconds for Best UPS */
+#	include "serial.h"
+#	define SER_WAIT_SEC	1	/* 3 seconds for Best UPS */
 #endif	/* QX_SERIAL */
 
 #include "nutdrv_qx.h"
@@ -370,8 +370,7 @@ static void	qx_initbattery(void)
 		batt_packs_known = 1;
 	}
 
-	val = getval("battery_voltage_reports_one_pack");
-	if (val) {
+	if (testvar("battery_voltage_reports_one_pack")) {
 		battery_voltage_reports_one_pack = 1;
 		/* If we already have a battery.voltage reading from the device,
 		 * it is not yet "adjusted" to consider the multiplication for
@@ -758,6 +757,9 @@ static int	phoenix_command(const char *cmd, char *buf, size_t buflen)
 
 		case LIBUSB_ERROR_TIMEOUT:	/* Connection timed out */
 			break;
+
+		default:
+			break;
 		}
 
 		if (ret < 0) {
@@ -2257,7 +2259,7 @@ static qx_usb_device_id_t	qx_usb_id[] = {
 	{ USB_DEVICE(0x0001, 0x0000),	"ATCL FOR UPS",	"ATCL FOR UPS",		&fuji_subdriver },	/* Fuji UPSes */
 	{ USB_DEVICE(0x0001, 0x0000),	NULL,		NULL,			&krauler_subdriver },	/* Krauler UP-M500VA */
 	{ USB_DEVICE(0x0001, 0x0000),	NULL,		"MEC0003",		&snr_subdriver },	/* SNR-UPS-LID-XXXX UPSes */
-	{ USB_DEVICE(0x0925, 0x1234),	NULL,		NULL,					&armac_subdriver },	/* Armac UPS and maybe other richcomm-like or using old PowerManagerII software */
+	{ USB_DEVICE(0x0925, 0x1234),	NULL,		NULL,			&armac_subdriver },	/* Armac UPS and maybe other richcomm-like or using old PowerManagerII software */
 	/* End of list */
 	{ -1,	-1,	NULL,	NULL,	NULL }
 };
@@ -2872,7 +2874,7 @@ void	upsdrv_shutdown(void)
 }
 
 #ifdef QX_USB
-	#ifndef TESTING
+#	ifndef TESTING
 		static const struct {
 			const char	*name;
 			int		(*command)(const char *cmd, char *buf, size_t buflen);
@@ -2891,7 +2893,7 @@ void	upsdrv_shutdown(void)
 			{ "armac", &armac_command },
 			{ NULL, NULL }
 		};
-	#endif
+#	endif
 #endif
 
 
@@ -3194,13 +3196,13 @@ void	upsdrv_initups(void)
 /* Serial */
 #ifdef QX_SERIAL
 
-	#ifdef QX_USB
+#	ifdef QX_USB
 	if (!is_usb) {
-	#else
+#	else
 	{ /* scoping */
-	#endif	/* QX_USB */
+#	endif	/* QX_USB */
 
-	#ifndef TESTING
+#	ifndef TESTING
 
 		const struct {
 			const char	*val;
@@ -3261,13 +3263,13 @@ void	upsdrv_initups(void)
 		/* Allow some time to settle for the cablepower */
 		usleep(100000);
 
-	#endif	/* TESTING */
+#	endif	/* TESTING */
 
-	#ifdef QX_USB
+#	ifdef QX_USB
 	} else {	/* is_usb */
-	#else
+#	else
 	} /* end of scoping */
-	#endif	/* QX_USB */
+#	endif	/* QX_USB */
 
 #endif	/* QX_SERIAL */
 
@@ -3530,7 +3532,7 @@ static ssize_t	qx_command(const char *cmd, char *buf, size_t buflen)
 # endif
 #endif
 
-	#if WITH_LIBUSB_0_1			/* limit to libusb 0.1 implementation */
+#	if WITH_LIBUSB_0_1			/* limit to libusb 0.1 implementation */
 		case -EPERM:		/* Operation not permitted */
 			fatal_with_errno(EXIT_FAILURE, "Permissions problem");
 #ifndef HAVE___ATTRIBUTE__NORETURN
@@ -3543,7 +3545,7 @@ static ssize_t	qx_command(const char *cmd, char *buf, size_t buflen)
 #  pragma GCC diagnostic pop
 # endif
 #endif
-	#endif	/* WITH_LIBUSB_0_1 */
+#	endif	/* WITH_LIBUSB_0_1 */
 
 		case LIBUSB_ERROR_PIPE:	/* Broken pipe */
 			if (usb_clear_halt(udev, 0x81) == 0) {
diff --git a/drivers/nutdrv_qx.h b/drivers/nutdrv_qx.h
index 0c5f20688a..faffe717cc 100644
--- a/drivers/nutdrv_qx.h
+++ b/drivers/nutdrv_qx.h
@@ -26,11 +26,18 @@
 #ifndef NUTDRV_QX_H
 #define NUTDRV_QX_H
 
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include "config.h"
 
 /* For testing purposes */
 /*#define TESTING*/
diff --git a/drivers/nutdrv_qx_masterguard.c b/drivers/nutdrv_qx_masterguard.c
index 85a0cae0f6..f7e155b6a2 100644
--- a/drivers/nutdrv_qx_masterguard.c
+++ b/drivers/nutdrv_qx_masterguard.c
@@ -619,6 +619,8 @@ static int masterguard_setvar(item_t *item, char *value, const size_t valuelen)
 		case 's':
 			snprintf(value, valuelen, item->command, s);
 			break;
+		default:
+			break;
 	}
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_FORMAT_NONLITERAL
 #pragma GCC diagnostic pop
diff --git a/drivers/nutdrv_siemens_sitop.c b/drivers/nutdrv_siemens_sitop.c
index 1978f04022..f45bbc6dd4 100644
--- a/drivers/nutdrv_siemens_sitop.c
+++ b/drivers/nutdrv_siemens_sitop.c
@@ -56,7 +56,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Siemens SITOP UPS500 series driver"
-#define DRIVER_VERSION	"0.04"
+#define DRIVER_VERSION	"0.05"
 
 #define RX_BUFFER_SIZE 100
 
diff --git a/drivers/oneac.c b/drivers/oneac.c
index 0bb30d1f47..dcbac8e744 100644
--- a/drivers/oneac.c
+++ b/drivers/oneac.c
@@ -48,7 +48,7 @@ int setcmd(const char* varname, const char* setvalue);
 int instcmd(const char *cmdname, const char *extra);
 
 #define DRIVER_NAME	"Oneac EG/ON/OZ/OB UPS driver"
-#define DRIVER_VERSION	"0.82"
+#define DRIVER_VERSION	"0.83"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/openups-hid.c b/drivers/openups-hid.c
index 0a9eda9ad0..2e99c5440e 100644
--- a/drivers/openups-hid.c
+++ b/drivers/openups-hid.c
@@ -63,6 +63,8 @@ static void *get_voltage_multiplier(USBDevice_t *device)
 			ccharge_scale = 0.1; /* unverified */
 			cdischarge_scale = 0.1; /* unverified */
 			break;
+		default:
+			break;
 	}
 
 	upsdebugx(1, "vin_scale = %g; vout_scale = %g\n", vin_scale, vout_scale);
diff --git a/drivers/optiups.c b/drivers/optiups.c
index b3fe2634f2..9f4344d53c 100644
--- a/drivers/optiups.c
+++ b/drivers/optiups.c
@@ -28,7 +28,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Opti-UPS driver"
-#define DRIVER_VERSION "1.04"
+#define DRIVER_VERSION "1.05"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/phoenixcontact_modbus.c b/drivers/phoenixcontact_modbus.c
index 733989ef68..ab447e19af 100644
--- a/drivers/phoenixcontact_modbus.c
+++ b/drivers/phoenixcontact_modbus.c
@@ -24,7 +24,7 @@
 #include <modbus.h>
 
 #define DRIVER_NAME	"NUT PhoenixContact Modbus driver"
-#define DRIVER_VERSION	"0.03"
+#define DRIVER_VERSION	"0.04"
 
 #define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
 #define MODBUS_SLAVE_ID 192
diff --git a/drivers/pijuice.c b/drivers/pijuice.c
index 3e43bfdf89..09499f099a 100644
--- a/drivers/pijuice.c
+++ b/drivers/pijuice.c
@@ -22,6 +22,9 @@
 #include <sys/ioctl.h>
 #include "nut_stdint.h"
 
+#define DRIVER_NAME                         "PiJuice UPS driver"
+#define DRIVER_VERSION                      "0.12"
+
 /*
  * Linux I2C userland is a bit of a mess until distros refresh to
  * the i2c-tools 4.x release that profides i2c/smbus.h for userspace
@@ -217,9 +220,6 @@ static inline __u8* i2c_smbus_read_i2c_block_data(int file, __u8 command, __u8 l
 #define HIGH_BATTERY_THRESHOLD              75.0
 #define NOMINAL_BATTERY_VOLTAGE             4.18
 
-#define DRIVER_NAME                         "PiJuice UPS driver"
-#define DRIVER_VERSION                      "0.11"
-
 static uint8_t i2c_address    = 0x14;
 static uint8_t shutdown_delay = 30;
 
diff --git a/drivers/powercom-hid.c b/drivers/powercom-hid.c
index 5f838e1bc7..ebadc68841 100644
--- a/drivers/powercom-hid.c
+++ b/drivers/powercom-hid.c
@@ -4,7 +4,7 @@
  *  2003 - 2009	Arnaud Quette <ArnaudQuette@Eaton.com>
  *  2005 - 2006	Peter Selinger <selinger@users.sourceforge.net>
  *  2008 - 2009	Arjen de Korte <adkorte-guest@alioth.debian.org>
- *  2020 - 2022	Jim Klimov <jimklimov+nut@gmail.com>
+ *  2020 - 2024	Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -26,7 +26,7 @@
 #include "powercom-hid.h"
 #include "usb-common.h"
 
-#define POWERCOM_HID_VERSION	"PowerCOM HID 0.7"
+#define POWERCOM_HID_VERSION	"PowerCOM HID 0.71"
 /* FIXME: experimental flag to be put in upsdrv_info */
 
 /* PowerCOM */
@@ -54,6 +54,14 @@ static usb_device_id_t powercom_usb_device_table[] = {
 
 static char powercom_scratch_buf[32];
 
+/* Original subdriver code until version 0.7 sent shutdown commands
+ * in a wrong byte order than is needed by devices seen in the field
+ * in 2024. Just in case there are different firmwares, we provide
+ * a toggle to use old behavior. Maybe it was just a bug and nobody
+ * needs this fall-back...
+ */
+static char powercom_sdcmd_byte_order_fallback = 0;
+
 static const char *powercom_startup_fun(double value)
 {
 	uint16_t	i = value;
@@ -93,7 +101,14 @@ static const char *powercom_shutdown_fun(double value)
 {
 	uint16_t	i = value;
 
-	snprintf(powercom_scratch_buf, sizeof(powercom_scratch_buf), "%d", 60 * (i & 0x00FF) + (i >> 8));
+	if (powercom_sdcmd_byte_order_fallback) {
+		/* Legacy behavior */
+		snprintf(powercom_scratch_buf, sizeof(powercom_scratch_buf), "%d", 60 * (i & 0x00FF) + (i >> 8));
+	} else {
+		/* New default */
+		snprintf(powercom_scratch_buf, sizeof(powercom_scratch_buf), "%d", 60 * (i >> 8) + (i & 0x00FF));
+	}
+
 	upsdebugx(3, "%s: value = %.0f, buf = %s", __func__, value, powercom_scratch_buf);
 
 	return powercom_scratch_buf;
@@ -113,8 +128,16 @@ static double powercom_shutdown_nuf(const char *value)
 
 	val = (uint16_t)iv;
 	val = val ? val : 1;    /* 0 sets the maximum delay */
-	command = ((uint16_t)((val % 60) << 8)) + (uint16_t)(val / 60);
-	command |= 0x4000;	/* AC RESTART NORMAL ENABLE */
+	if (powercom_sdcmd_byte_order_fallback) {
+		/* Legacy behavior */
+		command = ((uint16_t)((val % 60) << 8)) + (uint16_t)(val / 60);
+		command |= 0x4000;	/* AC RESTART NORMAL ENABLE */
+	} else {
+		/* New default */
+		command = ((uint16_t)((val / 60) << 8)) + (uint16_t)(val % 60);
+		command |= 0x0040;	/* AC RESTART NORMAL ENABLE */
+	}
+
 	upsdebugx(3, "%s: value = %s, command = %04X", __func__, value, command);
 
 	return command;
@@ -138,8 +161,16 @@ static double powercom_stayoff_nuf(const char *value)
 
 	val = (uint16_t)iv;
 	val = val ? val : 1;    /* 0 sets the maximum delay */
-	command = ((uint16_t)((val % 60) << 8)) + (uint16_t)(val / 60);
-	command |= 0x8000;	/* AC RESTART NORMAL DISABLE */
+	if (powercom_sdcmd_byte_order_fallback) {
+		/* Legacy behavior */
+		command = ((uint16_t)((val % 60) << 8)) + (uint16_t)(val / 60);
+		command |= 0x8000;	/* AC RESTART NORMAL DISABLE */
+	} else {
+		/* New default */
+		command = ((uint16_t)((val / 60) << 8)) + (uint16_t)(val % 60);
+		command |= 0x0080;	/* AC RESTART NORMAL DISABLE */
+	}
+
 	upsdebugx(3, "%s: value = %s, command = %04X", __func__, value, command);
 
 	return command;
@@ -541,8 +572,9 @@ static int powercom_claim(HIDDevice_t *hd)
 		}
 		/* by default, reject, unless the productid option is given */
 		if (getval("productid")) {
-			return 1;
+			goto accept;
 		}
+		/* report and reject */
 		possibly_supported("PowerCOM", hd);
 		return 0;
 
@@ -551,12 +583,17 @@ static int powercom_claim(HIDDevice_t *hd)
 			interrupt_only = 1;
 			interrupt_size = 8;
 		}
-		return 1;
+		goto accept;
 
 	case NOT_SUPPORTED:
 	default:
 		return 0;
 	}
+
+accept:
+	powercom_sdcmd_byte_order_fallback = testvar("powercom_sdcmd_byte_order_fallback");
+
+	return 1;
 }
 
 subdriver_t powercom_subdriver = {
diff --git a/drivers/powercom.c b/drivers/powercom.c
index 8b22f74c84..d31e730b7c 100644
--- a/drivers/powercom.c
+++ b/drivers/powercom.c
@@ -83,10 +83,10 @@
 #include "main.h"
 #include "serial.h"
 #include "powercom.h"
-#include "math.h"
+#include "nut_float.h"
 
 #define DRIVER_NAME	"PowerCom protocol UPS driver"
-#define DRIVER_VERSION	"0.21"
+#define DRIVER_VERSION	"0.23"
 
 /* driver description structure */
 upsdrv_info_t	upsdrv_info = {
@@ -669,6 +669,7 @@ static float load_level(void)
 				case 1000:
 				case 1500:
 				case 2000: return raw_data[UPS_LOAD]*110.0/load1000i[voltage];
+				default: break;
 			}
 		}
 	} else if (!strcmp(types[type].name, "KIN")) {
diff --git a/drivers/powerman-pdu.c b/drivers/powerman-pdu.c
index 316950a47c..277bd4d347 100644
--- a/drivers/powerman-pdu.c
+++ b/drivers/powerman-pdu.c
@@ -23,7 +23,7 @@
 #include <libpowerman.h>	/* pm_err_t and other beasts */
 
 #define DRIVER_NAME	"Powerman PDU client driver"
-#define DRIVER_VERSION	"0.13"
+#define DRIVER_VERSION	"0.14"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/powerp-bin.c b/drivers/powerp-bin.c
index 0c7da014a0..3c6d74f00b 100644
--- a/drivers/powerp-bin.c
+++ b/drivers/powerp-bin.c
@@ -32,10 +32,9 @@
 
 #include "powerp-bin.h"
 #include "nut_stdint.h"
+#include "nut_float.h"
 
-#include <math.h>
-
-#define POWERPANEL_BIN_VERSION "Powerpanel-Binary 0.5"
+#define POWERPANEL_BIN_VERSION	"Powerpanel-Binary 0.60"
 
 typedef struct {
 	unsigned char	start;
diff --git a/drivers/powerp-txt.c b/drivers/powerp-txt.c
index 0390a7ca64..d13e8899a0 100644
--- a/drivers/powerp-txt.c
+++ b/drivers/powerp-txt.c
@@ -36,7 +36,7 @@
 
 #include <ctype.h>
 
-#define POWERPANEL_TEXT_VERSION "Powerpanel-Text 0.6"
+#define POWERPANEL_TEXT_VERSION	"Powerpanel-Text 0.60"
 
 typedef struct {
 	float          i_volt;
diff --git a/drivers/powerpanel.c b/drivers/powerpanel.c
index 9ec775784e..5600ad4f7c 100644
--- a/drivers/powerpanel.c
+++ b/drivers/powerpanel.c
@@ -36,7 +36,7 @@ static subdriver_t *subdriver[] = {
 };
 
 #define DRIVER_NAME	"CyberPower text/binary protocol UPS driver"
-#define DRIVER_VERSION	"0.29"
+#define DRIVER_VERSION	"0.30"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/powervar-hid.c b/drivers/powervar-hid.c
index a37978aa48..4821ca88c2 100644
--- a/drivers/powervar-hid.c
+++ b/drivers/powervar-hid.c
@@ -119,14 +119,16 @@ static int powervar_claim(HIDDevice_t *hd)
 	case POSSIBLY_SUPPORTED:
 		/* by default, reject, unless the productid option is given */
 		if (getval("productid")) {
-			usb->hid_rep_index = 1;
+			if (!getval("usb_hid_rep_index"))
+				usb->hid_rep_index = 1;
 			return 1;
 		}
 		possibly_supported("Powervar", hd);
 		return 0;
 
 	case SUPPORTED:
-		usb->hid_rep_index = 1;
+		if (!getval("usb_hid_rep_index"))
+			usb->hid_rep_index = 1;
 		return 1;
 
 	case NOT_SUPPORTED:
diff --git a/drivers/rhino.c b/drivers/rhino.c
index 6ceab04158..f312fab798 100644
--- a/drivers/rhino.c
+++ b/drivers/rhino.c
@@ -38,7 +38,7 @@
 #include "timehead.h"
 
 #define DRIVER_NAME	"Microsol Rhino UPS driver"
-#define DRIVER_VERSION	"0.53"
+#define DRIVER_VERSION	"0.54"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -464,6 +464,9 @@ CommReceive(const unsigned char *bufptr, ssize_t size)
 			break;
 		}
 
+		default:
+			break;
+
 	}
 
 	Waiting = 0;
diff --git a/drivers/richcomm_usb.c b/drivers/richcomm_usb.c
index 053144654b..766d3bba60 100644
--- a/drivers/richcomm_usb.c
+++ b/drivers/richcomm_usb.c
@@ -30,7 +30,7 @@
 
 /* driver version */
 #define DRIVER_NAME	"Richcomm dry-contact to USB driver"
-#define DRIVER_VERSION	"0.12"
+#define DRIVER_VERSION	"0.13"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -490,6 +490,9 @@ static int usb_device_open(usb_dev_handle **handlep, USBDevice_t *device, USBDev
 				case -2:
 					upsdebugx(4, "matcher: unspecified error");
 					goto next_device;
+
+				default:
+					break;
 				}
 			}
 #ifdef HAVE_LIBUSB_SET_AUTO_DETACH_KERNEL_DRIVER
@@ -743,6 +746,7 @@ void upsdrv_makevartable(void)
 {
 	/* allow -x vendor=X, vendorid=X, product=X, productid=X, serial=X */
 	/* TODO: Uncomment while addressing https://github.com/networkupstools/nut/issues/1768
-	nut_usb_addvars();
+	 * When fixing, see also tools/nut-scanner/scan_usb.c "exceptions".
+	 * nut_usb_addvars();
 	*/
 }
diff --git a/drivers/riello.c b/drivers/riello.c
index 28c992bfde..dc3a09796f 100644
--- a/drivers/riello.c
+++ b/drivers/riello.c
@@ -86,6 +86,8 @@ uint16_t riello_calc_CRC(uint8_t type, uint8_t *buff, uint16_t size, uint8_t che
 					CRC_Word += buff[i];
 			}
 			break;
+		default:
+			break;
 	}
 	return(CRC_Word);
 }
@@ -126,6 +128,8 @@ uint8_t riello_test_crc(uint8_t type, uint8_t *buff, uint16_t size, uint8_t chec
 			if (suma != CRC_Word)
 				return(1);
 			break;
+		default:
+			break;
 	}
 	return(0);
 }
@@ -944,6 +948,8 @@ uint8_t riello_header(uint8_t type, uint8_t a, uint8_t* length)
 			if ((buf_ptr_length==0) && (LAST_DATA[5]>0x20) && (LAST_DATA[4]==0x2))
 				return(1);
 			break;
+		default:
+			break;
 	}
 	return(0);
 }
@@ -963,6 +969,8 @@ uint8_t riello_tail(uint8_t type, uint8_t length)
 			if (LAST_DATA[5] == 0x03)
 				return(1);
 			break;
+		default:
+			break;
 	}
 	return(0);
 }
@@ -974,6 +982,8 @@ uint8_t riello_test_nak(uint8_t type, uint8_t* buffer)
 			if (buffer[3] == 0x15)
 				return(1);
 			break;
+		default:
+			break;
 	}
 	return(0);
 }
diff --git a/drivers/riello_ser.c b/drivers/riello_ser.c
index 6748fca83a..f15c785ef5 100644
--- a/drivers/riello_ser.c
+++ b/drivers/riello_ser.c
@@ -48,10 +48,10 @@
 #include "riello.h"
 
 #define DRIVER_NAME	"Riello serial driver"
-#define DRIVER_VERSION	"0.09"
+#define DRIVER_VERSION	"0.11"
 
-#define DEFAULT_OFFDELAY   5
-#define DEFAULT_BOOTDELAY  5
+#define DEFAULT_OFFDELAY   5  /*!< seconds (max 0xFF) */
+#define DEFAULT_BOOTDELAY  5  /*!< seconds (max 0xFF) */
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -76,6 +76,15 @@ static unsigned int bootdelay = DEFAULT_BOOTDELAY;
 
 static TRielloData DevData;
 
+/* Flag for estimation of battery.runtime and battery.charge */
+static int localcalculation = 0;
+static int localcalculation_logged = 0;
+/* NOTE: Do not change these default, they refer to battery.voltage.nominal=12.0
+ * and used in related maths later */
+static double batt_volt_nom = 12.0;
+static double batt_volt_low = 10.4;
+static double batt_volt_high = 13.0;
+
 /**********************************************************************
  * char_read (char *bytes, size_t size, int read_timeout)
  *
@@ -729,6 +738,7 @@ static int start_ups_comm(void)
 void upsdrv_initinfo(void)
 {
 	int ret;
+	const char *valN = NULL, *valL = NULL, *valH = NULL;
 
 	ret = start_ups_comm();
 
@@ -739,6 +749,15 @@ void upsdrv_initinfo(void)
 	else
 		upsdebugx(2, "Communication with UPS established");
 
+	if (testvar("localcalculation")) {
+		localcalculation = 1;
+		upsdebugx(1, "Will guesstimate battery charge and runtime "
+			"instead of trusting device readings (if any); "
+			"consider also setting default.battery.voltage.low "
+			"and default.battery.voltage.high for this device");
+	}
+	dstate_setinfo("driver.parameter.localcalculation", "%d", localcalculation);
+
 	if (typeRielloProtocol == DEV_RIELLOGPSER)
 		riello_parse_gi(&bufIn[0], &DevData);
 	else
@@ -770,13 +789,33 @@ void upsdrv_initinfo(void)
 	dstate_setinfo("ups.serial", "%s", (unsigned char*) DevData.Identification);
 	dstate_setinfo("ups.firmware", "%s", (unsigned char*) DevData.Version);
 
+	/* Is it set by user default/override configuration?
+	 * NOTE: "valN" is also used for a check just below.
+	 */
+	valN = dstate_getinfo("battery.voltage.nominal");
+	if (valN) {
+		batt_volt_nom = strtod(valN, NULL);
+		upsdebugx(1, "Using battery.voltage.nominal=%.1f "
+			"likely coming from user configuration",
+			batt_volt_nom);
+	}
+
 	if (typeRielloProtocol == DEV_RIELLOGPSER) {
 		if (get_ups_nominal() == 0) {
 			dstate_setinfo("ups.realpower.nominal", "%u", DevData.NomPowerKW);
 			dstate_setinfo("ups.power.nominal", "%u", DevData.NomPowerKVA);
 			dstate_setinfo("output.voltage.nominal", "%u", DevData.NominalUout);
 			dstate_setinfo("output.frequency.nominal", "%.1f", DevData.NomFout/10.0);
-			dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+
+			/* Is it set by user default/override configuration (see just above)? */
+			if (valN) {
+				upsdebugx(1, "...instead of battery.voltage.nominal=%u "
+					"reported by the device", DevData.NomUbat);
+			} else {
+				dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+				batt_volt_nom = (double)DevData.NomUbat;
+			}
+
 			dstate_setinfo("battery.capacity", "%u", DevData.NomBatCap);
 		}
 	}
@@ -786,11 +825,94 @@ void upsdrv_initinfo(void)
 			dstate_setinfo("ups.power.nominal", "%u", DevData.NomPowerKVA);
 			dstate_setinfo("output.voltage.nominal", "%u", DevData.NominalUout);
 			dstate_setinfo("output.frequency.nominal", "%.1f", DevData.NomFout/10.0);
-			dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+
+			/* Is it set by user default/override configuration (see just above)? */
+			if (valN) {
+				upsdebugx(1, "...instead of battery.voltage.nominal=%u "
+					"reported by the device", DevData.NomUbat);
+			} else {
+				dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+				batt_volt_nom = (double)DevData.NomUbat;
+			}
+
 			dstate_setinfo("battery.capacity", "%u", DevData.NomBatCap);
+		} else {
+			/* TOTHINK: Check the momentary reading of battery.voltage
+			 * or would it be too confusing (especially if it is above
+			 * 12V and might correspond to a discharged UPS when the
+			 * driver starts up after an outage?)
+			 * NOTE: DevData.Ubat would be scaled by 10!
+			 */
+			if (!valN) {
+				/* The nominal was not already set by user configuration... */
+				upsdebugx(1, "Using built-in default battery.voltage.nominal=%.1f",
+					batt_volt_nom);
+				dstate_setinfo("battery.voltage.nominal", "%.1f", batt_volt_nom);
+			}
+		}
+	}
+
+	/* We have a nominal voltage by now - either from user configuration
+	 * or from the device itself (or initial defaults for 12V). Do we have
+	 * any low/high range from HW/FW or defaults from ups.conf? */
+	valL = dstate_getinfo("battery.voltage.low");
+	valH = dstate_getinfo("battery.voltage.high");
+
+	{	/* scoping */
+		/* Pick a suitable low/high range (or keep built-in default).
+		 * The factor may be a count of battery packs in the UPS.
+		 */
+		int times12 = batt_volt_nom / 12;
+		if (times12 > 1) {
+			/* Scale up the range for 24V (X=2) etc. */
+			upsdebugx(3, "%s: Using %i times the voltage range of 12V PbAc battery",
+				__func__, times12);
+			batt_volt_low  *= times12;
+			batt_volt_high *= times12;
+		}
+	}
+
+	if (!valL && !valH) {
+		/* Both not set (NULL) => pick by nominal (X times 12V above). */
+		upsdebugx(3, "Neither battery.voltage.low=%.1f "
+			"nor battery.voltage.high=%.1f is set via "
+			"driver configuration or by device; keeping "
+			"at built-in default value (aligned "
+			"with battery.voltage.nominal=%.1f)",
+			batt_volt_low, batt_volt_high, batt_volt_nom);
+	} else {
+		if (valL) {
+			batt_volt_low = strtod(valL, NULL);
+			upsdebugx(2, "%s: Using battery.voltage.low=%.1f from device or settings",
+				__func__, batt_volt_low);
+		}
+
+		if (valH) {
+			batt_volt_high = strtod(valH, NULL);
+			upsdebugx(2, "%s: Using battery.voltage.high=%.1f from device or settings",
+				__func__, batt_volt_high);
+		}
+
+		/* If just one of those is set, then what? */
+		if (valL || valH) {
+			upsdebugx(1, "WARNING: Only one of battery.voltage.low=%.1f "
+				"or battery.voltage.high=%.1f is set via "
+				"driver configuration; keeping the other "
+				"at built-in default value (aligned "
+				"with battery.voltage.nominal=%.1f)",
+				batt_volt_low, batt_volt_high, batt_volt_nom);
+		} else {
+			upsdebugx(1, "Both of battery.voltage.low=%.1f "
+				"or battery.voltage.high=%.1f are set via "
+				"driver configuration; not aligning "
+				"with battery.voltage.nominal=%.1f",
+				batt_volt_low, batt_volt_high, batt_volt_nom);
 		}
 	}
 
+	/* Whatever the origin, make the values known via dstate */
+	dstate_setinfo("battery.voltage.low",  "%.1f", batt_volt_low);
+	dstate_setinfo("battery.voltage.high", "%.1f", batt_volt_high);
 
 	/* commands ----------------------------------------------- */
 	dstate_addcmd("load.off");
@@ -822,6 +944,12 @@ void upsdrv_updateinfo(void)
 	uint8_t getextendedOK;
 	static int countlost = 0;
 	int stat;
+	int battcharge;
+	float battruntime;
+	float upsloadfactor;
+#ifdef RIELLO_DYNAMIC_BATTVOLT_INFO
+	const char *val = NULL;
+#endif
 
 	upsdebugx(1, "countlost %d",countlost);
 
@@ -834,10 +962,13 @@ void upsdrv_updateinfo(void)
 		}
 	}
 
-	if (typeRielloProtocol == DEV_RIELLOGPSER)
+	if (typeRielloProtocol == DEV_RIELLOGPSER) {
 		stat = get_ups_status();
-	else
+		upsdebugx(1, "get_ups_status() %d", stat );
+	} else {
 		stat = get_ups_sentr();
+		upsdebugx(1, "get_ups_sentr() %d", stat );
+	}
 
 	if (stat < 0) {
 		if (countlost < COUNTLOST)
@@ -862,13 +993,75 @@ void upsdrv_updateinfo(void)
 	dstate_setinfo("output.frequency", "%.2f", DevData.Fout/10.0);
 	dstate_setinfo("battery.voltage", "%.1f", DevData.Ubat/10.0);
 
-	if ((DevData.BatCap < 0xFFFF) &&  (DevData.BatTime < 0xFFFF)) {
-		dstate_setinfo("battery.charge", "%u", DevData.BatCap);
-		dstate_setinfo("battery.runtime", "%u", DevData.BatTime*60);
+#ifdef RIELLO_DYNAMIC_BATTVOLT_INFO
+	/* Can be set via default.* or override.* driver options
+	 * if not served by the device HW/FW */
+	val = dstate_getinfo("battery.voltage.low");
+	if (val) {
+		batt_volt_low = strtod(val, NULL);
+	}
+
+	val = dstate_getinfo("battery.voltage.high");
+	if (val) {
+		batt_volt_high = strtod(val, NULL);
 	}
+#endif
+
+	if (localcalculation) {
+		/* NOTE: at this time "localcalculation" is a configuration toggle.
+		 * Maybe later it can be replaced by a common "runtimecal" setting. */
+		/* Considered "Ubat" physical range here (e.g. 10.7V to 12.9V) is
+		 * seen as "107" or "129" integers in the DevData properties: */
+		uint16_t	Ubat_low  = batt_volt_low  * 10;	/* e.g. 107 */
+		uint16_t	Ubat_high = batt_volt_high * 10;	/* e.g. 129 */
+		static int batt_volt_logged = 0;
+
+		if (!batt_volt_logged) {
+			upsdebugx(0, "\nUsing battery.voltage.low=%.1f and "
+				"battery.voltage.high=%.1f for \"localcalculation\" "
+				"guesstimates of battery.charge and battery.runtime",
+				batt_volt_low, batt_volt_high);
+			batt_volt_logged = 1;
+		}
 
-	if (DevData.Tsystem < 0xFF)
+		battcharge = ((DevData.Ubat <= Ubat_high) && (DevData.Ubat >= Ubat_low))
+			? (((DevData.Ubat - Ubat_low)*100) / (Ubat_high - Ubat_low))
+			: ((DevData.Ubat < Ubat_low) ? 0 : 100);
+		battruntime = (DevData.NomBatCap * DevData.NomUbat * 3600.0/DevData.NomPowerKW) * (battcharge/100.0);
+		upsloadfactor = (DevData.Pout1 > 0) ? (DevData.Pout1/100.0) : 1;
+
+		dstate_setinfo("battery.charge", "%u", battcharge);
+		dstate_setinfo("battery.runtime", "%.0f", battruntime/upsloadfactor);
+	}
+	else {
+		if (!localcalculation_logged) {
+			upsdebugx(0, "\nIf you don't see values for battery.charge and "
+				"battery.runtime or values are incorrect,"
+				"try setting \"localcalculation\" flag in \"ups.conf\" "
+				"options section for this driver!\n");
+			localcalculation_logged = 1;
+		}
+		if ((DevData.BatCap < 0xFFFF) && (DevData.BatTime < 0xFFFF)) {
+			/* Use values reported by the driver unless they are marked
+			 * invalid/unknown by HW/FW (all bits in the word are set).
+			 */
+			dstate_setinfo("battery.charge", "%u", DevData.BatCap);
+			dstate_setinfo("battery.runtime", "%u", DevData.BatTime*60);
+		}
+	}
+
+	if (DevData.Tsystem == 255) {
+		/* Use values reported by the driver unless they are marked
+		 * invalid/unknown by HW/FW (all bits in the word are set).
+		 */
+		/*dstate_setinfo("ups.temperature", "%u", 0);*/
+		upsdebugx(4, "Reported temperature value is 0xFF, "
+			"probably meaning \"-1\" for error or "
+			"missing sensor - ignored");
+	}
+	else if (DevData.Tsystem < 0xFF) {
 		dstate_setinfo("ups.temperature", "%u", DevData.Tsystem);
+	}
 
 	if (input_monophase) {
 		dstate_setinfo("input.voltage", "%u", DevData.Uinp1);
@@ -1032,6 +1225,8 @@ void upsdrv_makevartable(void)
 
 	/* allow '-x foo=<some value>' */
 	/* addvar(VAR_VALUE, "foo", "Override foo setting"); */
+
+	addvar(VAR_FLAG, "localcalculation", "Calculate battery charge and runtime locally");
 }
 
 void upsdrv_initups(void)
diff --git a/drivers/riello_usb.c b/drivers/riello_usb.c
index e965fd7830..fdc7de8246 100644
--- a/drivers/riello_usb.c
+++ b/drivers/riello_usb.c
@@ -8,6 +8,8 @@
  *
  * Copyright (C) 2012 - Elio Parisi <e.parisi@riello-ups.com>
  * Copyright (C) 2016   Eaton
+ * Copyright (C) 2022-2024 "amikot"
+ * Copyright (C) 2022-2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -34,7 +36,7 @@
 #include "riello.h"
 
 #define DRIVER_NAME	"Riello USB driver"
-#define DRIVER_VERSION	"0.11"
+#define DRIVER_VERSION	"0.13"
 
 #define DEFAULT_OFFDELAY   5  /*!< seconds (max 0xFF) */
 #define DEFAULT_BOOTDELAY  5  /*!< seconds (max 0xFF) */
@@ -68,6 +70,15 @@ static USBDevice_t usbdevice;
 static USBDeviceMatcher_t *reopen_matcher = NULL;
 static USBDeviceMatcher_t *regex_matcher = NULL;
 
+/* Flag for estimation of battery.runtime and battery.charge */
+static int localcalculation = 0;
+static int localcalculation_logged = 0;
+/* NOTE: Do not change these default, they refer to battery.voltage.nominal=12.0
+ * and used in related maths later */
+static double batt_volt_nom = 12.0;
+static double batt_volt_low = 10.4;
+static double batt_volt_high = 13.0;
+
 static int (*subdriver_command)(uint8_t *cmd, uint8_t *buf, uint16_t length, uint16_t buflen) = NULL;
 
 static void ussleep(useconds_t usec)
@@ -838,6 +849,8 @@ void upsdrv_makevartable(void)
 {
 	/* allow -x vendor=X, vendorid=X, product=X, productid=X, serial=X */
 	nut_usb_addvars();
+
+	addvar(VAR_FLAG, "localcalculation", "Calculate battery charge and runtime locally");
 }
 
 void upsdrv_initups(void)
@@ -940,6 +953,7 @@ void upsdrv_initups(void)
 void upsdrv_initinfo(void)
 {
 	int ret;
+	const char *valN = NULL, *valL = NULL, *valH = NULL;
 
 	ret = start_ups_comm();
 
@@ -950,6 +964,15 @@ void upsdrv_initinfo(void)
 	else
 		upsdebugx(2, "Communication with UPS established");
 
+	if (testvar("localcalculation")) {
+		localcalculation = 1;
+		upsdebugx(1, "Will guesstimate battery charge and runtime "
+			"instead of trusting device readings (if any); "
+			"consider also setting default.battery.voltage.low "
+			"and default.battery.voltage.high for this device");
+	}
+	dstate_setinfo("driver.parameter.localcalculation", "%d", localcalculation);
+
 	riello_parse_gi(&bufIn[0], &DevData);
 
 	gpser_error_control = DevData.Identif_bytes[4]-0x30;
@@ -978,15 +1001,110 @@ void upsdrv_initinfo(void)
 	dstate_setinfo("ups.serial", "%s", (unsigned char*) DevData.Identification);
 	dstate_setinfo("ups.firmware", "%s", (unsigned char*) DevData.Version);
 
+	/* Is it set by user default/override configuration?
+	 * NOTE: "valN" is also used for a check just below.
+	 */
+	valN = dstate_getinfo("battery.voltage.nominal");
+	if (valN) {
+		batt_volt_nom = strtod(valN, NULL);
+		upsdebugx(1, "Using battery.voltage.nominal=%.1f "
+			"likely coming from user configuration",
+			batt_volt_nom);
+	}
+
 	if (get_ups_nominal() == 0) {
 		dstate_setinfo("ups.realpower.nominal", "%u", DevData.NomPowerKW);
 		dstate_setinfo("ups.power.nominal", "%u", DevData.NomPowerKVA);
 		dstate_setinfo("output.voltage.nominal", "%u", DevData.NominalUout);
 		dstate_setinfo("output.frequency.nominal", "%.1f", DevData.NomFout/10.0);
-		dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+
+		/* Is it set by user default/override configuration (see just above)? */
+		if (valN) {
+			upsdebugx(1, "...instead of battery.voltage.nominal=%u "
+				"reported by the device", DevData.NomUbat);
+		} else {
+			dstate_setinfo("battery.voltage.nominal", "%u", DevData.NomUbat);
+			batt_volt_nom = (double)DevData.NomUbat;
+		}
+
 		dstate_setinfo("battery.capacity", "%u", DevData.NomBatCap);
+	} else {
+		/* TOTHINK: Check the momentary reading of battery.voltage
+		 * or would it be too confusing (especially if it is above
+		 * 12V and might correspond to a discharged UPS when the
+		 * driver starts up after an outage?)
+		 * NOTE: DevData.Ubat would be scaled by 10!
+		 */
+		if (!valN) {
+			/* The nominal was not already set by user configuration... */
+			upsdebugx(1, "Using built-in default battery.voltage.nominal=%.1f",
+				batt_volt_nom);
+			dstate_setinfo("battery.voltage.nominal", "%.1f", batt_volt_nom);
+		}
+	}
+
+	/* We have a nominal voltage by now - either from user configuration
+	 * or from the device itself (or initial defaults for 12V). Do we have
+	 * any low/high range from HW/FW or defaults from ups.conf? */
+	valL = dstate_getinfo("battery.voltage.low");
+	valH = dstate_getinfo("battery.voltage.high");
+
+	{	/* scoping */
+		/* Pick a suitable low/high range (or keep built-in default).
+		 * The factor may be a count of battery packs in the UPS.
+		 */
+		int times12 = batt_volt_nom / 12;
+		if (times12 > 1) {
+			/* Scale up the range for 24V (X=2) etc. */
+			upsdebugx(3, "%s: Using %i times the voltage range of 12V PbAc battery",
+				__func__, times12);
+			batt_volt_low  *= times12;
+			batt_volt_high *= times12;
+		}
 	}
 
+	if (!valL && !valH) {
+		/* Both not set (NULL) => pick by nominal (X times 12V above). */
+		upsdebugx(3, "Neither battery.voltage.low=%.1f "
+			"nor battery.voltage.high=%.1f is set via "
+			"driver configuration or by device; keeping "
+			"at built-in default value (aligned "
+			"with battery.voltage.nominal=%.1f)",
+			batt_volt_low, batt_volt_high, batt_volt_nom);
+	} else {
+		if (valL) {
+			batt_volt_low = strtod(valL, NULL);
+			upsdebugx(2, "%s: Using battery.voltage.low=%.1f from device or settings",
+				__func__, batt_volt_low);
+		}
+
+		if (valH) {
+			batt_volt_high = strtod(valH, NULL);
+			upsdebugx(2, "%s: Using battery.voltage.high=%.1f from device or settings",
+				__func__, batt_volt_high);
+		}
+
+		/* If just one of those is set, then what? */
+		if (valL || valH) {
+			upsdebugx(1, "WARNING: Only one of battery.voltage.low=%.1f "
+				"or battery.voltage.high=%.1f is set via "
+				"driver configuration; keeping the other "
+				"at built-in default value (aligned "
+				"with battery.voltage.nominal=%.1f)",
+				batt_volt_low, batt_volt_high, batt_volt_nom);
+		} else {
+			upsdebugx(1, "Both of battery.voltage.low=%.1f "
+				"or battery.voltage.high=%.1f are set via "
+				"driver configuration; not aligning "
+				"with battery.voltage.nominal=%.1f",
+				batt_volt_low, batt_volt_high, batt_volt_nom);
+		}
+	}
+
+	/* Whatever the origin, make the values known via dstate */
+	dstate_setinfo("battery.voltage.low",  "%.1f", batt_volt_low);
+	dstate_setinfo("battery.voltage.high", "%.1f", batt_volt_high);
+
 	/* commands ----------------------------------------------- */
 	dstate_addcmd("load.off");
 	dstate_addcmd("load.on");
@@ -1056,6 +1174,12 @@ void upsdrv_updateinfo(void)
 	uint8_t getextendedOK;
 	static int countlost = 0;
 	int stat;
+	int battcharge;
+	float battruntime;
+	float upsloadfactor;
+#ifdef RIELLO_DYNAMIC_BATTVOLT_INFO
+	const char *val = NULL;
+#endif
 
 	upsdebugx(1, "countlost %d",countlost);
 
@@ -1090,14 +1214,76 @@ void upsdrv_updateinfo(void)
 	dstate_setinfo("input.bypass.frequency", "%.2f", DevData.Fbypass/10.0);
 	dstate_setinfo("output.frequency", "%.2f", DevData.Fout/10.0);
 	dstate_setinfo("battery.voltage", "%.1f", DevData.Ubat/10.0);
-	if ((DevData.BatCap < 0xFFFF) &&  (DevData.BatTime < 0xFFFF)) {
-		dstate_setinfo("battery.charge", "%u", DevData.BatCap);
-		dstate_setinfo("battery.runtime", "%u", DevData.BatTime*60);
+
+#ifdef RIELLO_DYNAMIC_BATTVOLT_INFO
+	/* Can be set via default.* or override.* driver options
+	 * if not served by the device HW/FW */
+	val = dstate_getinfo("battery.voltage.low");
+	if (val) {
+		batt_volt_low = strtod(val, NULL);
 	}
 
-	if (DevData.Tsystem < 0xFF)
-		dstate_setinfo("ups.temperature", "%u", DevData.Tsystem);
+	val = dstate_getinfo("battery.voltage.high");
+	if (val) {
+		batt_volt_high = strtod(val, NULL);
+	}
+#endif
+
+	if (localcalculation) {
+		/* NOTE: at this time "localcalculation" is a configuration toggle.
+		 * Maybe later it can be replaced by a common "runtimecal" setting. */
+		/* Considered "Ubat" physical range here (e.g. 10.7V to 12.9V) is
+		 * seen as "107" or "129" integers in the DevData properties: */
+		uint16_t	Ubat_low  = batt_volt_low  * 10;	/* e.g. 107 */
+		uint16_t	Ubat_high = batt_volt_high * 10;	/* e.g. 129 */
+		static int batt_volt_logged = 0;
+
+		if (!batt_volt_logged) {
+			upsdebugx(0, "\nUsing battery.voltage.low=%.1f and "
+				"battery.voltage.high=%.1f for \"localcalculation\" "
+				"guesstimates of battery.charge and battery.runtime",
+				batt_volt_low, batt_volt_high);
+			batt_volt_logged = 1;
+		}
+
+		battcharge = ((DevData.Ubat <= Ubat_high) && (DevData.Ubat >= Ubat_low))
+			? (((DevData.Ubat - Ubat_low)*100) / (Ubat_high - Ubat_low))
+			: ((DevData.Ubat < Ubat_low) ? 0 : 100);
+		battruntime = (DevData.NomBatCap * DevData.NomUbat * 3600.0/DevData.NomPowerKW) * (battcharge/100.0);
+		upsloadfactor = (DevData.Pout1 > 0) ? (DevData.Pout1/100.0) : 1;
 
+		dstate_setinfo("battery.charge", "%u", battcharge);
+		dstate_setinfo("battery.runtime", "%.0f", battruntime/upsloadfactor);
+	}
+	else {
+		if (!localcalculation_logged) {
+			upsdebugx(0, "\nIf you don't see values for battery.charge and "
+				"battery.runtime or values are incorrect,"
+				"try setting \"localcalculation\" flag in \"ups.conf\" "
+				"options section for this driver!\n");
+			localcalculation_logged = 1;
+		}
+		if ((DevData.BatCap < 0xFFFF) && (DevData.BatTime < 0xFFFF)) {
+			/* Use values reported by the driver unless they are marked
+			 * invalid/unknown by HW/FW (all bits in the word are set).
+			 */
+			dstate_setinfo("battery.charge", "%u", DevData.BatCap);
+			dstate_setinfo("battery.runtime", "%u", DevData.BatTime*60);
+		}
+	}
+
+	if (DevData.Tsystem == 255) {
+		/* Use values reported by the driver unless they are marked
+		 * invalid/unknown by HW/FW (all bits in the word are set).
+		 */
+		/*dstate_setinfo("ups.temperature", "%u", 0);*/
+		upsdebugx(4, "Reported temperature value is 0xFF, "
+			"probably meaning \"-1\" for error or "
+			"missing sensor - ignored");
+	}
+	else if (DevData.Tsystem < 0xFF) {
+		dstate_setinfo("ups.temperature", "%u", DevData.Tsystem);
+	}
 
 	if (input_monophase) {
 		dstate_setinfo("input.voltage", "%u", DevData.Uinp1);
diff --git a/drivers/safenet.c b/drivers/safenet.c
index 68365463fa..351187419e 100644
--- a/drivers/safenet.c
+++ b/drivers/safenet.c
@@ -41,7 +41,7 @@
 #include "safenet.h"
 
 #define DRIVER_NAME	"Generic SafeNet UPS driver"
-#define DRIVER_VERSION	"1.80"
+#define DRIVER_VERSION	"1.81"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/serial.h b/drivers/serial.h
index 7987cb385d..cd8aa0fbe4 100644
--- a/drivers/serial.h
+++ b/drivers/serial.h
@@ -1,7 +1,13 @@
 #ifndef SERIAL_H_SEEN
 #define SERIAL_H_SEEN 1
 
-#include "config.h"	/* should be first */
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #include "attribute.h"
 
diff --git a/drivers/skel.c b/drivers/skel.c
index b5033672bb..9b45023832 100644
--- a/drivers/skel.c
+++ b/drivers/skel.c
@@ -22,7 +22,7 @@
 /* #define IGNCHARS	""	*/
 
 #define DRIVER_NAME	"Skeleton UPS driver"
-#define DRIVER_VERSION	"0.04"
+#define DRIVER_VERSION	"0.05"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/sms_ser.c b/drivers/sms_ser.c
index 02100634c9..7b0f840896 100644
--- a/drivers/sms_ser.c
+++ b/drivers/sms_ser.c
@@ -31,7 +31,7 @@
 #define ENDCHAR '\r'
 
 #define DRIVER_NAME "SMS Brazil UPS driver"
-#define DRIVER_VERSION "1.00"
+#define DRIVER_VERSION "1.01"
 
 #define QUERY_SIZE 7
 #define BUFFER_SIZE 18
diff --git a/drivers/snmp-ups.c b/drivers/snmp-ups.c
index 9e7e04ca3a..d6e2f6a89b 100644
--- a/drivers/snmp-ups.c
+++ b/drivers/snmp-ups.c
@@ -174,7 +174,7 @@ static const char *mibname;
 static const char *mibvers;
 
 #define DRIVER_NAME	"Generic SNMP UPS driver"
-#define DRIVER_VERSION	"1.30"
+#define DRIVER_VERSION	"1.31"
 
 /* driver description structure */
 upsdrv_info_t	upsdrv_info = {
@@ -259,8 +259,10 @@ void upsdrv_initinfo(void)
 			&& !(su_info_p->flags & SU_OUTLET_GROUP))
 		{
 			/* first check that this OID actually exists */
+
 			/* FIXME: daisychain commands support! */
 			su_addcmd(su_info_p);
+
 /*
 			if (nut_snmp_get(su_info_p->OID) != NULL) {
 				dstate_addcmd(su_info_p->info_type);
@@ -610,6 +612,7 @@ void upsdrv_initups(void)
 		}
 		printf("\nOverall this driver has loaded %d MIB-to-NUT mapping tables\n", i);
 		exit(EXIT_SUCCESS);
+		/* fatalx(EXIT_FAILURE, "Marking the exit code as failure since the driver is not started now"); */
 	}
 
 	/* init SNMP library, etc... */
@@ -1144,7 +1147,6 @@ static struct snmp_pdu **nut_snmp_walk(const char *OID, int max_iteration)
 			break;
 		}
 
-
 		if (!((status == STAT_SUCCESS) && (response->errstat == SNMP_ERR_NOERROR))) {
 			if (mibname == NULL) {
 				/* We are probing for proper mib - ignore errors */
@@ -2921,8 +2923,9 @@ bool_t daisychain_init(void)
 			if (devices_count == -1) {
 #endif /* WITH_SNMP_LKP_FUN */
 
-				if (nut_snmp_get_int(su_info_p->OID, &devices_count) == TRUE)
+				if (nut_snmp_get_int(su_info_p->OID, &devices_count) == TRUE) {
 					upsdebugx(1, "There are %ld device(s) present", devices_count);
+				}
 				else
 				{
 					upsdebugx(1, "Error: can't get the number of device(s) present!");
@@ -3312,7 +3315,7 @@ bool_t snmp_ups_walk(int mode)
 
 #ifdef COUNT_ITERATIONS
 			/* check stale elements only on each PN_STALE_RETRY iteration. */
-	 		if ((su_info_p->flags & SU_FLAG_STALE) &&
+			if ((su_info_p->flags & SU_FLAG_STALE) &&
 					(iterations % SU_STALE_RETRY) != 0)
 				continue;
 #endif
diff --git a/drivers/snmp-ups.h b/drivers/snmp-ups.h
index 83a3a25b98..c069d7bb3d 100644
--- a/drivers/snmp-ups.h
+++ b/drivers/snmp-ups.h
@@ -52,6 +52,14 @@
 #ifndef SNMP_UPS_H
 #define SNMP_UPS_H
 
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
+
 #include "nut_stdint.h"	/* uint32_t */
 
 /* FIXME: still needed?
@@ -76,6 +84,10 @@
 #undef PACKAGE_TARNAME
 #endif
 
+#ifdef PACKAGE_URL
+#undef PACKAGE_URL
+#endif
+
 #ifdef HAVE_DMALLOC_H
 #undef HAVE_DMALLOC_H
 #endif
@@ -89,9 +101,27 @@
 # endif
 #endif
 
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_PARAMETER)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+/* These tend to have inlined API implementations as empty braces,
+ * causing warnings about unused parameters.
+ */
 #include <net-snmp/net-snmp-config.h>
 #include <net-snmp/net-snmp-includes.h>
 
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_PARAMETER)
+# pragma GCC diagnostic pop
+#endif
+
 #ifndef ONE_SEC
 /* This macro name disappeared from net-snmp sources and headers
  * after v5.9 tag, and was replaced by explicit expression below: */
diff --git a/drivers/socomec_jbus.c b/drivers/socomec_jbus.c
index dc9e260ce0..76534512be 100644
--- a/drivers/socomec_jbus.c
+++ b/drivers/socomec_jbus.c
@@ -31,7 +31,7 @@
 #include <modbus.h>
 
 #define DRIVER_NAME	"Socomec jbus driver"
-#define DRIVER_VERSION	"0.07"
+#define DRIVER_VERSION	"0.08"
 
 #define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
 #define MODBUS_SLAVE_ID 1
diff --git a/drivers/solis.c b/drivers/solis.c
index ee0f0a456c..11120580bb 100644
--- a/drivers/solis.c
+++ b/drivers/solis.c
@@ -48,7 +48,7 @@
 #include "timehead.h"
 
 #define DRIVER_NAME	"Microsol Solis UPS driver"
-#define DRIVER_VERSION	"0.69"
+#define DRIVER_VERSION	"0.70"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
@@ -799,8 +799,10 @@ static void get_base_info(void) {
 		Model = "Solis 3.0";
 		break;
 	case 16:
-	  Model = "Microsol Back-Ups BZ1200-BR";
-	  break;
+		Model = "Microsol Back-Ups BZ1200-BR";
+		break;
+	default:
+		break;
 	}
 
 	/* if( isprogram ) */
diff --git a/drivers/tripplite.c b/drivers/tripplite.c
index f353c38a7e..cfb4d2230f 100644
--- a/drivers/tripplite.c
+++ b/drivers/tripplite.c
@@ -113,11 +113,11 @@
 #include "serial.h"
 #include "tripplite.h"
 #include "nut_stdint.h"
-#include <math.h>
+#include "nut_float.h"
 #include <ctype.h>
 
 #define DRIVER_NAME	"Tripp-Lite SmartUPS driver"
-#define DRIVER_VERSION	"0.94"
+#define DRIVER_VERSION	"0.96"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/tripplite_usb.c b/drivers/tripplite_usb.c
index 5dbc22f0c0..d441e783a4 100644
--- a/drivers/tripplite_usb.c
+++ b/drivers/tripplite_usb.c
@@ -132,12 +132,12 @@
 
 #include "main.h"
 #include "nut_libusb.h"
-#include <math.h>
+#include "nut_float.h"
 #include <ctype.h>
 #include "usb-common.h"
 
 #define DRIVER_NAME	"Tripp Lite OMNIVS / SMARTPRO driver"
-#define DRIVER_VERSION	"0.35"
+#define DRIVER_VERSION	"0.38"
 
 /* driver description structure */
 upsdrv_info_t	upsdrv_info = {
@@ -1493,6 +1493,8 @@ void upsdrv_updateinfo(void)
 				case '0':
 					dstate_setinfo("input.frequency.nominal", "%d", 50);
 					break;
+				default:
+					break;
 			}
 		}
 
diff --git a/drivers/tripplitesu.c b/drivers/tripplitesu.c
index 82d98eee88..fb6f42076a 100644
--- a/drivers/tripplitesu.c
+++ b/drivers/tripplitesu.c
@@ -126,7 +126,7 @@
 #include "nut_stdint.h"
 
 #define DRIVER_NAME	"Tripp Lite SmartOnline driver"
-#define DRIVER_VERSION	"0.07"
+#define DRIVER_VERSION	"0.08"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/drivers/upscode2.c b/drivers/upscode2.c
index 5dac03bf20..ee88ba74f8 100644
--- a/drivers/upscode2.c
+++ b/drivers/upscode2.c
@@ -43,7 +43,7 @@
 #include "nut_float.h"
 
 #define DRIVER_NAME	"UPScode II UPS driver"
-#define DRIVER_VERSION	"0.91"
+#define DRIVER_VERSION	"0.92"
 
 /* driver description structure */
 upsdrv_info_t	upsdrv_info = {
diff --git a/drivers/upsdrvctl.c b/drivers/upsdrvctl.c
index 1c8b6fd52c..e0662e3088 100644
--- a/drivers/upsdrvctl.c
+++ b/drivers/upsdrvctl.c
@@ -1,6 +1,9 @@
 /* upsdrvctl.c - UPS driver controller
 
-   Copyright (C) 2001  Russell Kroll <rkroll@exploits.org>
+   Copyright (C)
+   2001		Russell Kroll <rkroll@exploits.org>
+   2005 - 2017	Arnaud Quette <arnaud.quette@free.fr>
+   2017 - 2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -188,37 +191,56 @@ static void signal_driver_cmd(const ups_t *ups,
 )
 {
 #ifndef WIN32
+/* TODO: implement WIN32: https://github.com/networkupstools/nut/issues/1916
+ * Currently the codepath is not implemented below
+ */
 	char	pidfn[SMALLBUF];
 #endif
 	int	ret;
 
 #ifndef WIN32
-	if (cmd == SIGCMD_RELOAD_OR_ERROR)
+	if (cmd == SIGCMD_RELOAD_OR_ERROR || cmd == SIGCMD_EXIT)
 #else
-	if (cmd && !strcmp(cmd, SIGCMD_RELOAD_OR_ERROR))
+	if (cmd && (!strcmp(cmd, SIGCMD_RELOAD_OR_ERROR) || !strcmp(cmd, SIGCMD_EXIT)))
 #endif
 	{
 		/* not a signal, use socket protocol */
-		char buf[LARGEBUF];
+		char buf[LARGEBUF], cmdbuf[LARGEBUF];
 		struct timeval	tv;
+		char *cmdname = NULL;
 
-		upsdebugx(1, "Signalling UPS [%s]: %s",
-			ups->upsname, "driver.reload-or-error");
+#ifndef WIN32
+		if (cmd == SIGCMD_RELOAD_OR_ERROR)
+#else
+		if (!strcmp(cmd, SIGCMD_RELOAD_OR_ERROR))
+#endif
+			cmdname = "reload-or-error";
+		else
+#ifndef WIN32
+		if (cmd == SIGCMD_EXIT)
+#else
+		if (!strcmp(cmd, SIGCMD_EXIT))
+#endif
+			cmdname = "exit";
+
+		upsdebugx(1, "Signalling UPS [%s]: driver.%s",
+			ups->upsname, NUT_STRARG(cmdname));
 
-		if (testmode)
+		if (testmode || !cmdname)
 			return;
 
 		/* Post the query and wait for reply */
 		/* FIXME: coordinate with pollfreq? */
 		tv.tv_sec = 15;
 		tv.tv_usec = 0;
+		snprintf(cmdbuf, sizeof(cmdbuf), "INSTCMD driver.%s\n", cmdname);
 		ret = upsdrvquery_oneshot(ups->driver, ups->upsname,
-			"INSTCMD driver.reload-or-error\n",
-			buf, sizeof(buf), &tv);
+			cmdbuf, buf, sizeof(buf), &tv);
 		if (ret < 0) {
 			goto socket_error;
 		} else {
-			upslogx(LOG_INFO, "Request to reload-or-error returned code %d", ret);
+			upslogx(LOG_INFO, "Request for driver to %s returned code %d",
+				cmdname, ret);
 			if (ret != STAT_INSTCMD_HANDLED)
 				exec_error++;
 			/* TODO: Propagate "ret" to caller, eventually CLI exit-code? */
@@ -233,7 +255,7 @@ static void signal_driver_cmd(const ups_t *ups,
 	}
 
 #ifndef WIN32
-/* TODO: implement WIN32 */
+/* TODO: implement WIN32: https://github.com/networkupstools/nut/issues/1916 */
 /* handle generally signalling the UPS */
 	/* Real signals */
 #ifndef WIN32
@@ -281,11 +303,13 @@ static void signal_driver_cmd(const ups_t *ups,
 	if (testmode)
 		return;
 
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
 #ifndef WIN32
 	if (ups->pid == -1) {
-		ret = sendsignalfn(pidfn, cmd);
+		ret = sendsignalfn(pidfn, cmd, ups->driver, 0);
 	} else {
-		ret = sendsignalpid(ups->pid, cmd);
+		ret = sendsignalpid(ups->pid, cmd, ups->driver, 0);
 		/* reap zombie if this child died */
 		if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
 			upslog_with_errno(LOG_WARNING,
@@ -294,14 +318,16 @@ static void signal_driver_cmd(const ups_t *ups,
 		}
 	}
 #else
-	ret = sendsignal(pidfn, cmd);
+	ret = sendsignal(pidfn, cmd, 0);
 #endif
+	/* Restore the signal errors verbosity */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
 
 	if (ret < 0) {
 		upslog_with_errno(LOG_ERR, "Signalling %s failed: %d", pidfn, ret);
 		exec_error++;
 	}
-#endif	/* WIN32 */
+#endif	/* WIN32: https://github.com/networkupstools/nut/issues/1916 */
 }
 
 /* handle generally signalling the UPS with recently raised signal */
@@ -353,60 +379,63 @@ static void stop_driver(const ups_t *ups)
 	if (testmode)
 		return;
 
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
+
 #ifndef WIN32
 	if (ups->pid == -1) {
-		ret = sendsignalfn(pidfn, SIGTERM);
+		ret = sendsignalfn(pidfn, SIGTERM, ups->driver, 0);
 	} else {
-		ret = sendsignalpid(ups->pid, SIGTERM);
+		ret = sendsignalpid(ups->pid, SIGTERM, ups->driver, 0);
 		/* reap zombie if this child died */
 		if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
-			return;
+			goto clean_return;
 		}
 	}
 #else
-	ret = sendsignal(pidfn, COMMAND_STOP);
+	ret = sendsignal(pidfn, COMMAND_STOP, 0);
 #endif
 
 	if (ret < 0) {
 #ifndef WIN32
 		upsdebugx(2, "SIGTERM to %s failed, retrying with SIGKILL", pidfn);
 		if (ups->pid == -1) {
-			ret = sendsignalfn(pidfn, SIGKILL);
+			ret = sendsignalfn(pidfn, SIGKILL, ups->driver, 0);
 		} else {
-			ret = sendsignalpid(ups->pid, SIGKILL);
+			ret = sendsignalpid(ups->pid, SIGKILL, ups->driver, 0);
 			/* reap zombie if this child died */
 			if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
-				return;
+				goto clean_return;
 			}
 		}
 #else
 		upsdebugx(2, "Stopping %s failed, retrying again", pidfn);
-		ret = sendsignal(pidfn, COMMAND_STOP);
+		ret = sendsignal(pidfn, COMMAND_STOP, 0);
 #endif
 		if (ret < 0) {
 			upslog_with_errno(LOG_ERR, "Stopping %s failed", pidfn);
 			exec_error++;
-			return;
+			goto clean_return;
 		}
 	}
 
 	for (i = 0; i < 5 ; i++) {
 #ifndef WIN32
 		if (ups->pid == -1) {
-			ret = sendsignalfn(pidfn, 0);
+			ret = sendsignalfn(pidfn, 0, ups->driver, 0);
 		} else {
 			/* reap zombie if this child died */
 			if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
-					return;
+				goto clean_return;
 			}
-			ret = sendsignalpid(ups->pid, 0);
+			ret = sendsignalpid(ups->pid, 0, ups->driver, 0);
 		}
 #else
-		ret = sendsignalfn(pidfn, 0);
+		ret = sendsignalfn(pidfn, 0, ups->driver, 0);
 #endif
 		if (ret != 0) {
 			upsdebugx(2, "Sending signal to %s failed, driver is finally down or wrongly owned", pidfn);
-			return;
+			goto clean_return;
 		}
 		sleep(1);
 	}
@@ -414,32 +443,32 @@ static void stop_driver(const ups_t *ups)
 #ifndef WIN32
 	upslog_with_errno(LOG_ERR, "Stopping %s failed, retrying harder", pidfn);
 	if (ups->pid == -1) {
-		ret = sendsignalfn(pidfn, SIGKILL);
+		ret = sendsignalfn(pidfn, SIGKILL, ups->driver, 0);
 	} else {
 		/* reap zombie if this child died */
 		if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
-			return;
+			goto clean_return;
 		}
-		ret = sendsignalpid(ups->pid, SIGKILL);
+		ret = sendsignalpid(ups->pid, SIGKILL, ups->driver, 0);
 	}
 #else
 	upslog_with_errno(LOG_ERR, "Stopping %s failed, retrying again", pidfn);
-	ret = sendsignal(pidfn, COMMAND_STOP);
+	ret = sendsignal(pidfn, COMMAND_STOP, 0);
 #endif
 	if (ret == 0) {
 		for (i = 0; i < 5 ; i++) {
 #ifndef WIN32
 			if (ups->pid == -1) {
-				ret = sendsignalfn(pidfn, 0);
+				ret = sendsignalfn(pidfn, 0, ups->driver, 0);
 			} else {
 				/* reap zombie if this child died */
 				if (waitpid(ups->pid, NULL, WNOHANG) == ups->pid) {
-					return;
+					goto clean_return;
 				}
-				ret = sendsignalpid(ups->pid, 0);
+				ret = sendsignalpid(ups->pid, 0, ups->driver, 0);
 			}
 #else
-			ret = sendsignalfn(pidfn, 0);
+			ret = sendsignalfn(pidfn, 0, ups->driver, 0);
 #endif
 			if (ret != 0) {
 				upsdebugx(2, "Sending signal to %s failed, driver is finally down or wrongly owned", pidfn);
@@ -449,7 +478,7 @@ static void stop_driver(const ups_t *ups)
 				if (ups->pid == -1) {
 					unlink(pidfn);
 				}
-				return;
+				goto clean_return;
 			}
 			sleep(1);
 		}
@@ -457,6 +486,10 @@ static void stop_driver(const ups_t *ups)
 
 	upslog_with_errno(LOG_ERR, "Stopping %s failed", pidfn);
 	exec_error++;
+
+clean_return:
+	/* Restore the signal errors verbosity */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
 }
 
 void set_exit_flag(const int sig)
@@ -492,7 +525,7 @@ static void reset_signal_flag(void)
 }
 
 #ifndef WIN32
-/* TODO: Equivalent for WIN32 - see SIGCMD_RELOAD in upd and upsmon */
+/* TODO: Equivalent for WIN32 - see SIGCMD_RELOAD in upsd and upsmon */
 static void set_reload_flag(const
 #ifndef WIN32
 	int
@@ -516,6 +549,10 @@ static void set_reload_flag(const
 			break;
 # endif
 
+		case SIGCMD_EXIT:	/* Not even a signal, but a socket protocol action */
+			reload_flag = 15;
+			break;
+
 		case SIGCMD_RELOAD:     /* SIGHUP */
 		case SIGCMD_RELOAD_OR_ERROR:	/* Not even a signal, but a socket protocol action */
 		default:
@@ -768,6 +805,221 @@ static void forkexec(char *const argv[], const ups_t *ups)
 #endif
 }
 
+static void list_driver(const ups_t *ups)
+{
+	/* Just a short report: one config section name per line */
+	printf("%s\n", ups->upsname);
+}
+
+static void status_driver(const ups_t *ups)
+{
+	/* TODO: Options (global static) for details of configuration like
+	 * the driver name, serial, etc. or even current life-cycle status
+	 * (e.g. valid PID existence, data query via socket protocol...)
+	 */
+	static int	headerShown = 0;
+#ifndef WIN32
+	char	pidfn[SMALLBUF];
+	int	cmdret = -1;
+#endif
+	char	bufPid[LARGEBUF], *pidStrFromSocket = NULL,
+		bufStatus[LARGEBUF], *statusStrFromSocket = NULL;
+	int	pidAlive = -1,
+		qretPing = -1, qretPid = -1, qretStatus = -1,
+		nudl = nut_upsdrvquery_debug_level,
+		nsdl = nut_sendsignal_debug_level;
+	pid_t	pidFromFile = -1, pidFromSocket = -1;
+	struct timeval	tv;
+	udq_pipe_conn_t	*conn;
+
+	if (!ups) {
+		upsdebugx(1, "%s: skip due to ups==null", __func__);
+		return;
+	}
+
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
+#ifndef WIN32
+	snprintf(pidfn, sizeof(pidfn), "%s/%s-%s.pid", altpidpath(), ups->driver, ups->upsname);
+	pidFromFile = parsepidfile(pidfn);
+	if (pidFromFile >= 0) {                                                                                                                                                                                                                       /* this method actively reports errors, if any */
+		cmdret = sendsignalpid(pidFromFile, 0, ups->driver, 1);
+		/* returns zero for a successfully sent signal */
+		if (cmdret == 0)
+			pidAlive = 1;
+	}
+	upsdebugx(4, "%s: pidfn=%s pidFromFile=%" PRIiMAX " cmdret=%d pidAlive=%d",
+		__func__, pidfn, (intmax_t)pidFromFile, cmdret, pidAlive);
+#else
+/*	// FIXME: We actually have no probing signals over pipe so far,
+	// and sending 0 (NULL here) is proven unsafe
+	// Instead we will try below with PID learned from pipe
+	snprintf(pidfn, sizeof(pidfn), "%s-%s", ups->driver, ups->upsname);
+	cmdret = sendsignal(pidfn, COMMAND_RELOAD, 1);
+	upsdebugx(4, "%s: pipe pidfn=%s cmdret=%d", __func__, pidfn, cmdret);
+ */
+#endif
+
+	/* Hush the fopen(socketfile) in upsdrvquery_connect_drvname_upsname() */
+	nut_upsdrvquery_debug_level = 0;
+	conn = upsdrvquery_connect_drvname_upsname(ups->driver, ups->upsname);
+	nut_upsdrvquery_debug_level = nudl;
+
+	if (conn && VALID_FD(conn->sockfd)) {
+		upsdebugx(3, "%s: connected", __func__);
+		/* Post the query and wait for reply */
+		/* FIXME: coordinate with pollfreq? */
+		tv.tv_sec = 3;
+		tv.tv_usec = 0;
+
+		memset(bufPid, 0, sizeof(bufPid));
+
+		/* Involves a PING/PONG check, and more;
+		 * returns -1 on error */
+		upsdebugx(3, "%s: upsdrvquery_prepare", __func__);
+		qretPing = upsdrvquery_prepare(conn, tv);
+
+		if (qretPing >= 0) {
+			qretPing = STAT_INSTCMD_HANDLED;
+
+			/* No TRACKING in queries below */
+			memset(bufPid, 0, sizeof(bufPid));
+
+			upsdebugx(3, "%s: upsdrvquery_write GETPID", __func__);
+			if (upsdrvquery_write(conn, "GETPID\n") >= 0
+			&&  (qretPid = upsdrvquery_read_timeout(conn, tv)) >= 1
+			&&  (!strncmp(conn->buf, "PID ", 4))
+			) {
+				size_t	l;
+				upsdebugx(4, "%s: upsdrvquery_read GETPID", __func__);
+				snprintf(bufPid, sizeof(bufPid), "%s", conn->buf + 4);
+				upsdebugx(4, "%s: upsdrvquery_read GETPID 2", __func__);
+				l = strlen(bufPid);
+				pidStrFromSocket = bufPid;
+				if (bufPid[l - 1] == '\n')
+					bufPid[l - 1] = '\0';
+				qretPid = STAT_INSTCMD_HANDLED;
+				pidFromSocket = parsepid(pidStrFromSocket);
+				if (errno != 0)
+					pidFromSocket = -1;
+			} else {
+				/* query failed or returned not a PID<something> */
+				qretPid = -1;
+			}
+		}
+
+		if (qretPid == STAT_INSTCMD_HANDLED) {
+			memset(bufStatus, 0, sizeof(bufStatus));
+#ifdef WIN32
+			/* Allow a new read to happen later */
+			conn->newread = 1;
+#endif
+
+			upsdebugx(3, "%s: upsdrvquery_write DUMPSTATUS", __func__);
+			if (upsdrvquery_write(conn, "DUMPSTATUS\n") >= 0
+			&&  (qretStatus = upsdrvquery_read_timeout(conn, tv)) >= 1
+			) {
+				char	*buf;
+
+				upsdebugx(4, "%s: upsdrvquery_read DUMPSTATUS", __func__);
+				/* save before strtok mangles it */
+				snprintf(bufStatus, sizeof(bufStatus), "%s", conn->buf);
+
+				upsdebugx(4, "%s: upsdrvquery_read DUMPSTATUS 2", __func__);
+				for (buf = strtok(bufStatus, "\n"); buf; buf = strtok(NULL, "\n")) {
+					if (statusStrFromSocket) {
+						/* New loop, NUL byte was set if needed */
+						break;
+					}
+
+					if (!strncmp(buf, "SETINFO ups.status ", 19)) {
+						statusStrFromSocket = buf + 19;
+						qretStatus = STAT_INSTCMD_HANDLED;
+						/* continue to loop, to clear '\n' to '\0' */
+					}
+
+					if (!strncmp(buf, "DUMPDONE\n", 9)) {
+						/* New loop, NUL byte was set if needed */
+						break;
+					}
+				}
+			} else {
+				/* query failed or did not return SETINFO ups.status ... */
+				qretStatus = -1;
+			}
+		}
+	} else {
+		upsdebugx(3, "%s: not connected", __func__);
+	}
+
+	upsdebugx(3, "%s: close socket", __func__);
+	upsdrvquery_close(conn);
+	if (conn) {
+		upsdebugx(4, "%s: free socket", __func__);
+		free(conn);
+		conn = NULL;
+	}
+
+	if (pidFromFile < 0 && pidFromSocket >= 0) {
+		upsdebugx(3, "%s: PID was not available from a file, but was "
+			"from Socket Protocol; check if it is alive instead",
+			__func__);
+
+		pidAlive = checkprocname(pidFromSocket, ups->driver);
+		upsdebugx(4, "%s: pidFromSocket=%" PRIiMAX " pidAlive=%d",
+			__func__, (intmax_t)pidFromSocket, pidAlive);
+	} else if (pidAlive < 0 && pidFromSocket >= 0 && (pidFromFile != pidFromSocket)) {
+		upsdebugx(3, "%s: PID value was available from a file, but was "
+			"not found running or valid; another one is available "
+			"from Socket Protocol; check if it is alive instead",
+			__func__);
+
+		pidAlive = checkprocname(pidFromSocket, ups->driver);
+		upsdebugx(4, "%s: pidFromSocket=%" PRIiMAX " pidAlive=%d",
+			__func__, (intmax_t)pidFromSocket, pidAlive);
+	}
+
+	/* Complete any cached (error) writes before the next lines,
+	 * more so on WIN32 */
+	fflush(stderr);
+	fflush(stdout);
+	usleep(1000);
+
+	if (!headerShown) {
+		printf("%-11s\t%11s\t%s\t%s\t%s\t%s\t%s\n",
+			"UPSNAME",
+			"UPSDRV",
+			"RUNNING",
+			"PF_PID",
+			"S_RESPONSIVE",
+			"S_PID",
+			"S_STATUS"
+			);
+		headerShown = 1;
+	}
+
+	upsdebugx(2, "%s: raw values: pidAlive=%d "
+		"pidFromFile=%" PRIiMAX " pidFromSocket=%" PRIiMAX " "
+		"qretPing=%d qretPid=%d qretStatus=%d",
+		__func__, pidAlive,
+		(intmax_t)(pidFromFile), (intmax_t)(pidFromSocket),
+		qretPing, qretPid, qretStatus
+		);
+
+	printf("%-11s\t%11s\t%s\t%" PRIiMAX "\t%s\t%s\t%s\n",
+		ups->upsname, ups->driver,
+		((pidFromFile < 0 && pidFromSocket < 0) || (pidAlive < 0)
+		 ? "N/A" : (pidAlive > 0 ? "RUNNING" : "STOPPED")),
+		(intmax_t)(pidFromFile),
+		((qretPing == STAT_INSTCMD_HANDLED) ? "RESPONSIVE" : "NOT_RESPONSIVE"),
+		(pidStrFromSocket ? pidStrFromSocket : "N/A"),
+		((qretStatus == STAT_INSTCMD_HANDLED) ? NUT_STRARG(statusStrFromSocket) : "")
+		);
+	fflush(stdout);
+
+	nut_sendsignal_debug_level = nsdl;
+}
+
 static void start_driver(const ups_t *ups)
 {
 	char	*argv[10];
@@ -920,8 +1172,11 @@ static void help(const char *progname)
 
 static void help(const char *arg_progname)
 {
-	printf("Starts and stops UPS drivers via ups.conf.\n\n");
-	printf("usage: %s [OPTIONS] (start | stop | shutdown) [<ups>]\n\n", arg_progname);
+	print_banner_once(arg_progname, 2);
+	printf("UPS driver controller: Starts and stops UPS drivers via ups.conf.\n\n");
+
+	printf("usage: %s [OPTIONS] (start | stop | shutdown | status) [<ups>]\n\n", arg_progname);
+	printf("usage: %s [OPTIONS] (list | -l) [<ups>]\n\n", arg_progname);
 	printf("usage: %s [OPTIONS] -c <command> [<ups>]\n\n", arg_progname);
 
 	printf("Common options:\n");
@@ -935,11 +1190,15 @@ static void help(const char *arg_progname)
 	printf("  -FF			driver stays foregrounded and still saves the PID file\n");
 	printf("  -B			driver(s) stay backgrounded even if debugging is bumped\n");
 
-	printf("Signalling a running driver:\n");
+	printf("\nListing known driver(s):\n");
+	printf("  -l | list		list all device driver confgurations that can be managed\n");
+	printf("  -l | list <ups>	only try to list the specified device driver confgurations (error if unresolved)\n");
+
+	printf("\nSignalling a running driver:\n");
 	printf("  -c <command>		send <command> via signal to running driver(s)\n");
 	printf("              		supported commands:\n");
 #ifndef WIN32
-/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds */
+/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds: https://github.com/networkupstools/nut/issues/1916 */
 	printf("              		- data-dump: if the driver still has STDOUT attached (maybe\n");
 	printf("              		  to log), dump its currently collected information there\n");
 	printf("              		- reload: re-read configuration files, ignoring changed\n");
@@ -952,7 +1211,7 @@ static void help(const char *arg_progname)
 	printf("              		  based on that count, so the caller can decide the fate of\n");
 	printf("              		  the currently running driver instance\n");
 #ifndef WIN32
-/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds */
+/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds: https://github.com/networkupstools/nut/issues/1916 */
 # ifdef SIGCMD_RELOAD_OR_RESTART
 	printf("              		- reload-or-restart: re-read configuration files (close the\n");
 	printf("              		  old driver instance device connection if needed, and have\n");
@@ -962,14 +1221,21 @@ static void help(const char *arg_progname)
 	printf("              		  driver instance if needed, so an external caller like the\n");
 	printf("              		  systemd or SMF frameworks would start another copy)\n");
 #endif /* WIN32 */
+	printf("              		- exit: tell the currently running driver instance to just exit\n");
+	printf("              		  (so an external caller like the new driver instance, or the\n");
+	printf("              		  systemd or SMF frameworks would start another copy)\n");
 
-	printf("Driver life cycle options:\n");
+	printf("\nDriver life cycle options:\n");
 	printf("  start			start all UPS drivers in ups.conf\n");
-	printf("  start	<ups>		only start driver for UPS <ups>\n");
+	printf("  start <ups>		only start driver for UPS <ups>\n");
 	printf("  stop			stop all UPS drivers in ups.conf\n");
 	printf("  stop <ups>		only stop driver for UPS <ups>\n");
 	printf("  shutdown		shutdown all UPS drivers in ups.conf\n");
 	printf("  shutdown <ups>	only shutdown UPS <ups>\n");
+	printf("  status		query status for all UPS drivers in ups.conf\n");
+	printf("  status <ups>		only query status for driver for UPS <ups>\n");
+	printf("              		Fields: UPSNAME UPSDRV RUNNING PF_PID S_RESPONSIVE S_PID S_STATUS\n");
+	printf("              		(PF_* = according to PID file, if any; S_* = via socket protocol)\n");
 
 	exit(EXIT_SUCCESS);
 }
@@ -1037,16 +1303,27 @@ static void send_one_driver(void (*command_func)(const ups_t *), const char *arg
 /* walk UPS table and send command to all UPSes according to sdorder */
 static void send_all_drivers(void (*command_func)(const ups_t *))
 {
-	ups_t	*ups;
+	ups_t	*ups = upstable;
 	int	i;
 
-	if (!upstable)
+	if (!ups)
 		fatalx(EXIT_FAILURE, "Error: no UPS definitions found in ups.conf");
 
 	exec_error = 0;
 	exec_timeout = 0;
+
+	if (command_func == &list_driver || command_func == &status_driver) {
+		while (ups) {
+			command_func(ups);
+			ups = ups->next;
+		}
+
+		fflush(stdout);
+		return;
+	}
+
 	if (command_func != &shutdown_driver) {
-		ups = upstable;
+		/* e.g. start_driver or stop_driver */
 
 		/* Only warn when relevant - got more than one device to start */
 		if (command_func == &start_driver
@@ -1080,8 +1357,6 @@ static void send_all_drivers(void (*command_func)(const ups_t *))
 
 	/* Orderly processing of shutdowns */
 	for (i = 0; i <= maxsdorder; i++) {
-		ups = upstable;
-
 		while (ups) {
 			if (ups->sdorder == i)
 				command_func(ups);
@@ -1133,13 +1408,15 @@ static void exit_cleanup(void)
 int main(int argc, char **argv)
 {
 	int	i, lastarg = 0;
-	char	*prog;
-
-	printf("Network UPS Tools - UPS driver controller %s\n",
-		UPS_VERSION);
+	char	*prog, *command_name = NULL, progdesc[LARGEBUF];
 
 	prog = argv[0];
-	while ((i = getopt(argc, argv, "+htu:r:DdFBVc:")) != -1) {
+
+	/* Historically special banner*/
+	snprintf(progdesc, sizeof(progdesc), "%s - UPS driver controller", xbasename(prog));
+	print_banner_once(progdesc, 0);
+
+	while ((i = getopt(argc, argv, "+htu:r:DdFBVc:l")) != -1) {
 		switch(i) {
 			case 'r':
 				pt_root = optarg;
@@ -1154,6 +1431,10 @@ int main(int argc, char **argv)
 				break;
 
 			case 'V':
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(progdesc, 1);
+				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
 
 			case 'D':
@@ -1184,12 +1465,17 @@ int main(int argc, char **argv)
 						"sent with option -%c. Try -h for help.", i);
 				}
 				command = &signal_driver;
+				command_name = "signal";
 
 				if (!strncmp(optarg, "reload-or-error", strlen(optarg))) {
 					signal_flag = SIGCMD_RELOAD_OR_ERROR;
 				}
+				else
+				if (!strncmp(optarg, "exit", strlen(optarg))) {
+					signal_flag = SIGCMD_EXIT;
+				}
 #ifndef WIN32
-/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds */
+/* FIXME: port event loop from upsd/upsmon to allow messaging fellow drivers in WIN32 builds: https://github.com/networkupstools/nut/issues/1916 */
 				else
 				if (!strncmp(optarg, "dump", strlen(optarg))) {
 					signal_flag = SIGCMD_DATA_DUMP;
@@ -1208,7 +1494,7 @@ int main(int argc, char **argv)
 				if (!strncmp(optarg, "reload-or-exit", strlen(optarg))) {
 					signal_flag = SIGCMD_RELOAD_OR_EXIT;
 				}
-#endif	/* WIN32 */
+#endif	/* WIN32: https://github.com/networkupstools/nut/issues/1916 */
 
 				/* bad command given */
 				if (!signal_flag) {
@@ -1218,17 +1504,27 @@ int main(int argc, char **argv)
 
 				pt_cmd = optarg;
 #ifndef WIN32
-				upsdebugx(1, "Will send signal %d (%s) for command '%s' "
-					"to already-running driver (if any) and exit",
-					signal_flag, strsignal(signal_flag), optarg);
+				if (signal_flag > 0)
+					upsdebugx(1, "Will send signal %d (%s) for command '%s' "
+						"to already-running driver (if any) and exit",
+						signal_flag, strsignal(signal_flag), optarg);
+				else
+					upsdebugx(1, "Will send request for command '%s' (internal code %d) "
+						"to already-running driver (if any) and exit",
+						optarg, signal_flag);
 #else
 				upsdebugx(1, "Will send request '%s' for command '%s' "
 					"to already-running driver (if any) and exit",
 					signal_flag, optarg);
 #endif	/* WIN32 */
 				break;
+			case 'l':
+				command = &list_driver;
+				command_name = "list";
+				break;
 			case 'h':
 			default:
+				/* not progdesc, shows details of its own */
 				help(prog);
 		}
 	}
@@ -1259,28 +1555,28 @@ int main(int argc, char **argv)
 			nut_debug_level = 2;
 	}
 
-	if (nut_debug_level_passthrough == 0) {
-		upsdebugx(2, "\n"
-			"If you're not a NUT core developer, chances are that you're told to enable debugging\n"
-			"to see why a driver isn't working for you. We're sorry for the confusion, but this is\n"
-			"the 'upsdrvctl' wrapper, not the driver you're interested in.\n\n"
-			"Below you'll find one or more lines starting with 'exec:' followed by an absolute\n"
-			"path to the driver binary and some command line option. This is what the driver\n"
-			"starts and you need to copy and paste that line and append the debug flags to that\n"
-			"line (less the 'exec:' prefix).\n\n"
-			"Alternately, provide an additional '-d' (lower-case) parameter to 'upsdrvctl' to\n"
-			"pass its current debug level to the launched driver, and '-B' keeps it backgrounded.\n");
-	}
-
+	/* Note: argv is incremented above, so [0] is currently the next
+	 * CLI keyword after options */
 	if (!command) {
 		if (!strcmp(argv[0], "start")) {
 			command = &start_driver;
+			command_name = argv[0];
 		} else
 		if (!strcmp(argv[0], "stop")) {
 			command = &stop_driver;
+			command_name = argv[0];
 		} else
 		if (!strcmp(argv[0], "shutdown")) {
 			command = &shutdown_driver;
+			command_name = argv[0];
+		} else
+		if (!strcmp(argv[0], "list")) {
+			command = &list_driver;
+			command_name = argv[0];
+		} else
+		if (!strcmp(argv[0], "status")) {
+			command = &status_driver;
+			command_name = argv[0];
 		}
 		lastarg = 1;
 	}
@@ -1288,6 +1584,19 @@ int main(int argc, char **argv)
 	if (!command)
 		fatalx(EXIT_FAILURE, "Error: unrecognized command [%s]", argv[0]);
 
+	if (nut_debug_level_passthrough == 0 && (command == &start_driver || command == &shutdown_driver)) {
+		upsdebugx(2, "\n"
+			"If you're not a NUT core developer, chances are that you're told to enable debugging\n"
+			"to see why a driver isn't working for you. We're sorry for the confusion, but this is\n"
+			"the 'upsdrvctl' wrapper, not the driver you're interested in.\n\n"
+			"Below you'll find one or more lines starting with 'exec:' followed by an absolute\n"
+			"path to the driver binary and some command line option. This is what the driver\n"
+			"starts and you need to copy and paste that line and append the debug flags to that\n"
+			"line (less the 'exec:' prefix).\n\n"
+			"Alternately, provide an additional '-d' (lower-case) parameter to 'upsdrvctl' to\n"
+			"pass its current debug level to the launched driver, and '-B' keeps it backgrounded.\n");
+	}
+
 #ifndef WIN32
 	driverpath = xstrdup(DRVPATH);	/* set default */
 #else
@@ -1308,19 +1617,39 @@ int main(int argc, char **argv)
 		}
 
 		upsdebugx(1, "upsdrvctl commanding all drivers (%d found): %s",
-			upscount, (pt_cmd ? pt_cmd : NUT_STRARG(argv[lastarg])));
+			upscount, (pt_cmd ? pt_cmd : NUT_STRARG(command_name)));
 		send_all_drivers(command);
 	} else
 	if (argc == (lastarg + 1)) {
 		upscount = 1;
 		upsdebugx(1, "upsdrvctl commanding one driver (%s): %s",
-			argv[lastarg], (pt_cmd ? pt_cmd : NUT_STRARG(argv[lastarg - 1])));
+			argv[lastarg], (pt_cmd ? pt_cmd : NUT_STRARG(command_name)));
 		send_one_driver(command, argv[lastarg]);
 	} else {
 		fatalx(EXIT_FAILURE, "Error: extra arguments left on command line\n"
 			"(common options should be before a command and UPS name)");
 	}
 
+#if (defined(WITH_SOLARIS_SMF) && WITH_SOLARIS_SMF) || (defined(HAVE_SYSTEMD) && HAVE_SYSTEMD)
+	if (!getenv("NUT_QUIET_INIT_NDE_WARNING")
+	&&  (command == &start_driver || command == &stop_driver || command == &shutdown_driver)
+	) {
+# if (defined(WITH_SOLARIS_SMF) && WITH_SOLARIS_SMF)
+		char *fwk = "SMF";
+# else
+#  if (defined(HAVE_SYSTEMD) && HAVE_SYSTEMD)
+		char *fwk = "systemd";
+#  endif
+# endif
+		upslogx(LOG_WARNING, "WARNING: %s was called directly on a system with %s support.\n"
+			"    Please consider using 'upsdrvsvcctl' instead, to avoid conflicts with\n"
+			"    nut-driver service instances prepared by 'nut-driver-enumerator'!",
+			prog, fwk);
+		upsdebugx(1, "For more details see https://github.com/networkupstools/nut/wiki/nut%%E2%%80%%90driver%%E2%%80%%90enumerator-(NDE)");
+		upsdebugx(1, "To silence this warning export NUT_QUIET_INIT_NDE_WARNING with any value");
+	}
+#endif
+
 	/* Note that the numeric value here is not precise (it reflects
 	 * the number of "timeouts" which grows with amount of drivers
 	 * and retries. Below we re-check each driver to convert the
diff --git a/drivers/upsdrvquery.c b/drivers/upsdrvquery.c
index 0936631ab5..31bb8e94e1 100644
--- a/drivers/upsdrvquery.c
+++ b/drivers/upsdrvquery.c
@@ -2,7 +2,7 @@
                    tracked until a response arrives, returning
                    that line and closing a connection
 
-   Copyright (C) 2023  Jim Klimov <jimklimov+nut@gmail.com>
+   Copyright (C) 2023-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -39,6 +39,19 @@
 #include "upsdrvquery.h"
 #include "nut_stdint.h"
 
+/* Normally the upsdrvquery*() methods call upslogx() to report issues
+ * such as failed fopen() of Unix socket file, or a dialog timeout or
+ * different error.
+ * In a few cases we call these methods opportunistically, and so if
+ * they fail - we do not care enough to raise a lot of "scary noise";
+ * the caller can take care of logging as/if needed.
+ * This variable and its values are a bit of internal detail between
+ * certain NUT programs to hush the low-level reports when they are
+ * not being otherwise debugged (e.g. nut_debug_level < 1).
+ * Default value allows all those messages to appear.
+ */
+int nut_upsdrvquery_debug_level = NUT_UPSDRVQUERY_DEBUG_LEVEL_DEFAULT;
+
 udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 	udq_pipe_conn_t	*conn = (udq_pipe_conn_t*)xcalloc(1, sizeof(udq_pipe_conn_t));
 
@@ -54,13 +67,15 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 	conn->sockfd = socket(AF_UNIX, SOCK_STREAM, 0);
 
 	if (conn->sockfd < 0) {
-		upslog_with_errno(LOG_ERR, "open socket");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "open socket");
 		free(conn);
 		return NULL;
 	}
 
 	if (connect(conn->sockfd, (struct sockaddr *) &sa, sizeof(sa)) < 0) {
-		upslog_with_errno(LOG_ERR, "connect to driver socket at %s", sockfn);
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "connect to driver socket at %s", sockfn);
 		close(conn->sockfd);
 		free(conn);
 		return NULL;
@@ -68,14 +83,16 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 
 	ret = fcntl(conn->sockfd, F_GETFL, 0);
 	if (ret < 0) {
-		upslog_with_errno(LOG_ERR, "fcntl get on driver socket %s failed", sockfn);
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "fcntl get on driver socket %s failed", sockfn);
 		close(conn->sockfd);
 		free(conn);
 		return NULL;
 	}
 
 	if (fcntl(conn->sockfd, F_SETFL, ret | O_NDELAY) < 0) {
-		upslog_with_errno(LOG_ERR, "fcntl set O_NDELAY on driver socket %s failed", sockfn);
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "fcntl set O_NDELAY on driver socket %s failed", sockfn);
 		close(conn->sockfd);
 		free(conn);
 		return NULL;
@@ -84,7 +101,8 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 	BOOL	result = WaitNamedPipe(sockfn, NMPWAIT_USE_DEFAULT_WAIT);
 
 	if (result == FALSE) {
-		upslog_with_errno(LOG_ERR, "WaitNamedPipe : %d\n", GetLastError());
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "WaitNamedPipe : %d\n", GetLastError());
 		return NULL;
 	}
 
@@ -99,7 +117,8 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 			NULL);          /* no template file */
 
 	if (conn->sockfd == INVALID_HANDLE_VALUE) {
-		upslog_with_errno(LOG_ERR, "CreateFile : %d\n", GetLastError());
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "CreateFile : %d\n", GetLastError());
 		free(conn);
 		return NULL;
 	}
@@ -114,7 +133,8 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 	);
 
 	if (conn->overlapped.hEvent == NULL) {
-		upslogx(LOG_ERR, "Can't create event for reading event log");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslogx(LOG_ERR, "Can't create event for reading event log");
 		free(conn);
 		return NULL;
 	}
@@ -138,27 +158,49 @@ udq_pipe_conn_t *upsdrvquery_connect(const char *sockfn) {
 }
 
 udq_pipe_conn_t *upsdrvquery_connect_drvname_upsname(const char *drvname, const char *upsname) {
-	char	pidfn[SMALLBUF];
+	char	sockname[SMALLBUF];
 #ifndef WIN32
 	struct stat     fs;
-	snprintf(pidfn, sizeof(pidfn), "%s/%s-%s",
+	snprintf(sockname, sizeof(sockname), "%s/%s-%s",
 		dflt_statepath(), drvname, upsname);
-	check_unix_socket_filename(pidfn);
-	if (stat(pidfn, &fs)) {
-		upslog_with_errno(LOG_ERR, "Can't open %s", pidfn);
+	check_unix_socket_filename(sockname);
+	if (stat(sockname, &fs)) {
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "Can't open %s", sockname);
 		return NULL;
 	}
 #else
-	snprintf(pidfn, sizeof(pidfn), "\\\\.\\pipe\\%s-%s", drvname, upsname);
+	snprintf(sockname, sizeof(sockname), "\\\\.\\pipe\\%s-%s", drvname, upsname);
 #endif  /* WIN32 */
 
-	return upsdrvquery_connect(pidfn);
+	return upsdrvquery_connect(sockname);
 }
 
 void upsdrvquery_close(udq_pipe_conn_t *conn) {
+#ifdef WIN32
+	int	loggedOut = 0;
+#endif  /* WIN32 */
+
 	if (!conn)
 		return;
 
+	if (VALID_FD(conn->sockfd)) {
+		int	nudl = nut_upsdrvquery_debug_level;
+		ssize_t ret;
+		upsdebugx(5, "%s: closing driver socket, try to say goodbye", __func__);
+		ret = upsdrvquery_write(conn, "LOGOUT\n");
+		if (7 <= ret) {
+			upsdebugx(5, "%s: okay", __func__);
+#ifdef WIN32
+			loggedOut = 1;
+#endif  /* WIN32 */
+			usleep(1000000);
+		} else {
+			upsdebugx(5, "%s: must have been closed on the other side", __func__);
+		}
+		nut_upsdrvquery_debug_level = nudl;
+	}
+
 #ifndef WIN32
 	if (VALID_FD(conn->sockfd))
 		close(conn->sockfd);
@@ -169,10 +211,11 @@ void upsdrvquery_close(udq_pipe_conn_t *conn) {
 	memset(&(conn->overlapped), 0, sizeof(conn->overlapped));
 
 	if (VALID_FD(conn->sockfd)) {
-		if (DisconnectNamedPipe(conn->sockfd) == 0) {
-			upslogx(LOG_ERR,
-				"DisconnectNamedPipe error : %d",
-				(int)GetLastError());
+		if (DisconnectNamedPipe(conn->sockfd) == 0 && !loggedOut) {
+			if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+				upslogx(LOG_ERR,
+					"DisconnectNamedPipe error : %d",
+					(int)GetLastError());
 		}
 		CloseHandle(conn->sockfd);
 	}
@@ -196,7 +239,8 @@ ssize_t upsdrvquery_read_timeout(udq_pipe_conn_t *conn, struct timeval tv) {
 #endif
 
 	if (!conn || INVALID_FD(conn->sockfd)) {
-		upslog_with_errno(LOG_ERR, "socket not initialized");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "socket not initialized");
 		return -1;
 	}
 
@@ -205,7 +249,8 @@ ssize_t upsdrvquery_read_timeout(udq_pipe_conn_t *conn, struct timeval tv) {
 	FD_SET(conn->sockfd, &rfds);
 
 	if (select(conn->sockfd + 1, &rfds, NULL, NULL, &tv) < 0) {
-		upslog_with_errno(LOG_ERR, "select with socket");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_DIALOG)
+			upslog_with_errno(LOG_ERR, "select with socket");
 		/* upsdrvquery_close(conn); */
 		return -1;
 	}
@@ -219,7 +264,8 @@ ssize_t upsdrvquery_read_timeout(udq_pipe_conn_t *conn, struct timeval tv) {
 	ret = read(conn->sockfd, conn->buf, sizeof(conn->buf));
 #else
 /*
-	upslog_with_errno(LOG_ERR, "Support for this platform is not currently implemented");
+	if (nut_debug_level > 0 || nut_upsdrvquery_debug_level > 0)
+		upslog_with_errno(LOG_ERR, "Support for this platform is not currently implemented");
 	return -1;
 */
 
@@ -333,7 +379,8 @@ ssize_t upsdrvquery_write(udq_pipe_conn_t *conn, const char *buf) {
 	upsdebugx(5, "%s: write to driver socket: %s", __func__, buf);
 
 	if (!conn || INVALID_FD(conn->sockfd)) {
-		upslog_with_errno(LOG_ERR, "socket not initialized");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT)
+			upslog_with_errno(LOG_ERR, "socket not initialized");
 		return -1;
 	}
 
@@ -341,7 +388,8 @@ ssize_t upsdrvquery_write(udq_pipe_conn_t *conn, const char *buf) {
 	ret = write(conn->sockfd, buf, buflen);
 
 	if (ret < 0 || ret != (int)buflen) {
-		upslog_with_errno(LOG_ERR, "Write to socket %d failed", conn->sockfd);
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_DIALOG)
+			upslog_with_errno(LOG_ERR, "Write to socket %d failed", conn->sockfd);
 		goto socket_error;
 	}
 
@@ -349,7 +397,8 @@ ssize_t upsdrvquery_write(udq_pipe_conn_t *conn, const char *buf) {
 #else
 	result = WriteFile(conn->sockfd, buf, buflen, &bytesWritten, NULL);
 	if (result == 0 || bytesWritten != (DWORD)buflen) {
-		upslog_with_errno(LOG_ERR, "Write to handle %p failed", conn->sockfd);
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_DIALOG)
+			upslog_with_errno(LOG_ERR, "Write to handle %p failed", conn->sockfd);
 		goto socket_error;
 	}
 
@@ -433,7 +482,8 @@ ssize_t upsdrvquery_prepare(udq_pipe_conn_t *conn, struct timeval tv) {
 	if (upsdrvquery_read_timeout(conn, tv) < 1)
 		goto socket_error;
 	if (strcmp(conn->buf, "ON")) {
-		upslog_with_errno(LOG_ERR, "Driver does not have TRACKING support enabled");
+		if (nut_debug_level > 0 || nut_upsdrvquery_debug_level >= NUT_UPSDRVQUERY_DEBUG_LEVEL_DIALOG)
+			upslog_with_errno(LOG_ERR, "Driver does not have TRACKING support enabled");
 		goto socket_error;
 	}
 */
diff --git a/drivers/upsdrvquery.h b/drivers/upsdrvquery.h
index 6a7b879d6b..e3854940b2 100644
--- a/drivers/upsdrvquery.h
+++ b/drivers/upsdrvquery.h
@@ -2,7 +2,7 @@
                    tracked until a response arrives, returning
                    that line and closing a connection
 
-   Copyright (C) 2023  Jim Klimov <jimklimov+nut@gmail.com>
+   Copyright (C) 2023-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,7 +20,7 @@
 */
 
 #ifndef NUT_UPSDRVQUERY_H_SEEN
-#define NUT_UPSDRVQUERY_H_SEEN
+#define NUT_UPSDRVQUERY_H_SEEN 1
 
 #include "common.h"	/* TYPE_FD etc. */
 #include "timehead.h"
@@ -48,4 +48,11 @@ ssize_t upsdrvquery_request(udq_pipe_conn_t *conn, struct timeval tv, const char
 /* if buf != NULL, last reply is copied there */
 ssize_t upsdrvquery_oneshot(const char *drvname, const char *upsname, const char *query, char *buf, const size_t bufsz, struct timeval *tv);
 
+/* Internal toggle for some NUT programs that deal with Unix socket chatter.
+ * For a detailed rationale comment see upsdrvquery.c */
+extern int nut_upsdrvquery_debug_level;
+#define NUT_UPSDRVQUERY_DEBUG_LEVEL_DEFAULT	6
+#define NUT_UPSDRVQUERY_DEBUG_LEVEL_CONNECT	5
+#define NUT_UPSDRVQUERY_DEBUG_LEVEL_DIALOG	4
+
 #endif	/* NUT_UPSDRVQUERY_H_SEEN */
diff --git a/drivers/upshandler.h b/drivers/upshandler.h
index fea10bc20c..78e6ffef0a 100644
--- a/drivers/upshandler.h
+++ b/drivers/upshandler.h
@@ -22,18 +22,20 @@
 
 /* return values for instcmd */
 enum {
-	STAT_INSTCMD_HANDLED = 0,	/* completed successfully */
-	STAT_INSTCMD_UNKNOWN,		/* unspecified error */
-	STAT_INSTCMD_INVALID,		/* invalid command */
-	STAT_INSTCMD_FAILED		/* command failed */
+	STAT_INSTCMD_HANDLED = 0,		/* completed successfully */
+	STAT_INSTCMD_UNKNOWN,			/* unspecified error */
+	STAT_INSTCMD_INVALID,			/* invalid command */
+	STAT_INSTCMD_FAILED,			/* command failed */
+	STAT_INSTCMD_CONVERSION_FAILED	/* could not convert value */
 };
 
 /* return values for setvar */
 enum {
-	STAT_SET_HANDLED = 0,	/* completed successfully */
-	STAT_SET_UNKNOWN,	/* unspecified error */
-	STAT_SET_INVALID,	/* not writeable */
-	STAT_SET_FAILED		/* writing failed */
+	STAT_SET_HANDLED = 0,			/* completed successfully */
+	STAT_SET_UNKNOWN,				/* unspecified error */
+	STAT_SET_INVALID,				/* not writeable */
+	STAT_SET_FAILED,				/* writing failed */
+	STAT_SET_CONVERSION_FAILED		/* could not convert value from string */
 };
 
 /* structure for funcs that get called by msg parse routine */
diff --git a/drivers/usb-common.c b/drivers/usb-common.c
index 6c10860ef8..42721a6afa 100644
--- a/drivers/usb-common.c
+++ b/drivers/usb-common.c
@@ -100,13 +100,13 @@ static int match_function_exact(USBDevice_t *hd, void *privdata)
 	}
 #endif
 #if (defined WITH_USB_BUSPORT) && (WITH_USB_BUSPORT)
-  #ifdef DEBUG_EXACT_MATCH_BUSPORT
+# ifdef DEBUG_EXACT_MATCH_BUSPORT
 	if (strcmp_null(hd->BusPort, data->BusPort) != 0) {
 		upsdebugx(2, "%s: failed match of %s: %s != %s",
 		    __func__, "BusPort", hd->BusPort, data->BusPort);
 		return 0;
 	}
-  #endif
+# endif
 #endif
 #ifdef DEBUG_EXACT_MATCH_DEVICE
 	if (strcmp_null(hd->Device, data->Device) != 0) {
@@ -153,6 +153,13 @@ int USBNewExactMatcher(USBDeviceMatcher_t **matcher, USBDevice_t *hd)
 #ifdef DEBUG_EXACT_MATCH_DEVICE
 	data->Device = hd->Device ? strdup(hd->Device) : NULL;
 #endif
+
+	/* NOTE: Callers must pre-initialize to NULL! */
+	if (matcher && *matcher) {
+		free(*matcher);
+		*matcher = NULL;
+	}
+
 	*matcher = m;
 
 	return 0;
@@ -334,6 +341,12 @@ int USBNewRegexMatcher(USBDeviceMatcher_t **matcher, char **regex, int cflags)
 		}
 	}
 
+	/* NOTE: Callers must pre-initialize to NULL! */
+	if (matcher && *matcher) {
+		free(*matcher);
+		*matcher = NULL;
+	}
+
 	*matcher = m;
 
 	return 0;
@@ -397,3 +410,91 @@ void warn_if_bad_usb_port_filename(const char *fn) {
 		__func__, fn);
 	return;
 }
+
+/* Retries were introduced for "Tripp Lite" devices, see
+ * https://github.com/networkupstools/nut/issues/414
+ */
+#define MAX_STRING_DESC_TRIES 3
+
+/* API neutral, handles retries.
+ * Note for future development: a variant of this code is adapted into
+ * tools/nut-scanner/scan_usb.c - please keep in sync if changing here.
+ */
+static int nut_usb_get_string_descriptor(
+	usb_dev_handle *udev,
+	int StringIdx,
+	int langid,
+	char *buf,
+	size_t buflen)
+{
+	int ret = -1;
+	int tries = MAX_STRING_DESC_TRIES;
+
+	while (tries--) {
+		ret = usb_get_string(udev, (usb_ctrl_strindex)StringIdx, langid, (usb_ctrl_charbuf)buf, buflen);
+		if (ret >= 0) {
+			break;
+		} else if (tries) {
+			upsdebugx(1, "%s: string descriptor %d request failed, retrying...", __func__, StringIdx);
+			usleep(50000);	/* 50 ms, might help in some cases */
+		}
+	}
+	return ret;
+}
+
+/* API neutral, assumes en_US if langid descriptor is broken.
+ * Note for future development: a variant of this code is adapted into
+ * tools/nut-scanner/scan_usb.c - please keep in sync if changing here.
+ */
+int nut_usb_get_string(
+	usb_dev_handle *udev,
+	int StringIdx,
+	char *buf,
+	size_t buflen)
+{
+	int ret;
+	char buffer[255];
+	int langid;
+	int len;
+	int i;
+
+	if (!udev || StringIdx < 1 || StringIdx > 255) {
+		return -1;
+	}
+
+	/* request langid descriptor */
+	ret = nut_usb_get_string_descriptor(udev, 0, 0, buffer, 4);
+	if (ret < 0)
+		return ret;
+
+	if (ret == 4 && buffer[0] >= 4 && buffer[1] == USB_DT_STRING) {
+		langid = buffer[2] | (buffer[3] << 8);
+	} else {
+		upsdebugx(1, "%s: Broken language identifier, assuming en_US", __func__);
+		langid = 0x0409;
+	}
+
+	/* retrieve string in preferred language */
+	ret = nut_usb_get_string_descriptor(udev, StringIdx, langid, buffer, sizeof(buffer));
+	if (ret < 0) {
+#ifdef WIN32
+		/* only for libusb0 ? */
+		errno = -ret;
+#endif
+		return ret;
+	}
+
+	/* translate simple UTF-16LE to 8-bit */
+	len = ret < (int)buflen ? ret : (int)buflen;
+	len = len / 2 - 1;	/* 16-bit characters, without header */
+	len = len < (int)buflen - 1 ? len : (int)buflen - 1;	/* reserve for null terminator */
+	for (i = 0; i < len; i++) {
+		if (buffer[2 + i * 2 + 1] == 0)
+			buf[i] = buffer[2 + i * 2];
+		else
+			buf[i] = '?';	/* not decoded */
+	}
+	buf[i] = '\0';
+
+	return len;
+}
diff --git a/drivers/usb-common.h b/drivers/usb-common.h
index 4f151ee8ac..b71bed8a06 100644
--- a/drivers/usb-common.h
+++ b/drivers/usb-common.h
@@ -57,7 +57,13 @@
 #ifndef NUT_USB_COMMON_H
 #define NUT_USB_COMMON_H
 
-#include "config.h"	/* be sure to know all about the system config */
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 /* Note: usb-common.h (this file) is included by nut_libusb.h,
  * so not looping the includes ;)
@@ -107,79 +113,79 @@
  * any use-case.
  */
  typedef uint8_t usb_ctrl_requesttype;
- #define USB_CTRL_REQUESTTYPE_MIN	0
- #define USB_CTRL_REQUESTTYPE_MAX	UINT8_MAX
+# define USB_CTRL_REQUESTTYPE_MIN	0
+# define USB_CTRL_REQUESTTYPE_MAX	UINT8_MAX
 
  typedef uint8_t usb_ctrl_request;
- #define USB_CTRL_REQUEST_MIN	0
- #define USB_CTRL_REQUEST_MAX	UINT8_MAX
+# define USB_CTRL_REQUEST_MIN	0
+# define USB_CTRL_REQUEST_MAX	UINT8_MAX
 
  typedef unsigned char usb_ctrl_endpoint;
- #define USB_CTRL_ENDPOINT_MIN	0
- #define USB_CTRL_ENDPOINT_MAX	UCHAR_MAX
+# define USB_CTRL_ENDPOINT_MIN	0
+# define USB_CTRL_ENDPOINT_MAX	UCHAR_MAX
 
  typedef uint16_t usb_ctrl_msgvalue;
- #define USB_CTRL_MSGVALUE_MIN	0
- #define USB_CTRL_MSGVALUE_MAX	UINT16_MAX
+# define USB_CTRL_MSGVALUE_MIN	0
+# define USB_CTRL_MSGVALUE_MAX	UINT16_MAX
 
  typedef uint8_t usb_ctrl_cfgindex;
- #define USB_CTRL_CFGINDEX_MIN	0
- #define USB_CTRL_CFGINDEX_MAX	UINT8_MAX
+# define USB_CTRL_CFGINDEX_MIN	0
+# define USB_CTRL_CFGINDEX_MAX	UINT8_MAX
 
  typedef uint16_t usb_ctrl_repindex;
- #define USB_CTRL_REPINDEX_MIN	0
- #define USB_CTRL_REPINDEX_MAX	UINT16_MAX
+# define USB_CTRL_REPINDEX_MIN	0
+# define USB_CTRL_REPINDEX_MAX	UINT16_MAX
 
  typedef uint8_t usb_ctrl_strindex;
- #define USB_CTRL_STRINDEX_MIN	0
- #define USB_CTRL_STRINDEX_MAX	UINT8_MAX
+# define USB_CTRL_STRINDEX_MIN	0
+# define USB_CTRL_STRINDEX_MAX	UINT8_MAX
 
  typedef uint8_t usb_ctrl_descindex;
- #define USB_CTRL_DESCINDEX_MIN	0
- #define USB_CTRL_DESCINDEX_MAX	UINT8_MAX
+# define USB_CTRL_DESCINDEX_MIN	0
+# define USB_CTRL_DESCINDEX_MAX	UINT8_MAX
 
  typedef unsigned char* usb_ctrl_charbuf;
  typedef unsigned char usb_ctrl_char;
- #define USB_CTRL_CHAR_MIN	0
- #define USB_CTRL_CHAR_MAX	UCHAR_MAX
+# define USB_CTRL_CHAR_MIN	0
+# define USB_CTRL_CHAR_MAX	UCHAR_MAX
 
  /* Here MIN/MAX should not matter much, type mostly used for casting */
  typedef uint16_t usb_ctrl_charbufsize;
- #define USB_CTRL_CHARBUFSIZE_MIN	0
- #define USB_CTRL_CHARBUFSIZE_MAX	UINT16_MAX
- #define PRI_NUT_USB_CTRL_CHARBUFSIZE PRIu16
+# define USB_CTRL_CHARBUFSIZE_MIN	0
+# define USB_CTRL_CHARBUFSIZE_MAX	UINT16_MAX
+# define PRI_NUT_USB_CTRL_CHARBUFSIZE PRIu16
 
  typedef unsigned int usb_ctrl_timeout_msec;	/* in milliseconds */
 	/* Note: there does not seem to be a standard type
 	 * for milliseconds, like there is an useconds_t */
- #define USB_CTRL_TIMEOUTMSEC_MIN	0
- #define USB_CTRL_TIMEOUTMSEC_MAX	UINT_MAX
+# define USB_CTRL_TIMEOUTMSEC_MIN	0
+# define USB_CTRL_TIMEOUTMSEC_MAX	UINT_MAX
 
  /* defines */
- #define USB_CLASS_PER_INTERFACE	LIBUSB_CLASS_PER_INTERFACE
- #define USB_DT_STRING				LIBUSB_DT_STRING
- #define USB_ENDPOINT_IN			LIBUSB_ENDPOINT_IN
- #define USB_ENDPOINT_OUT			LIBUSB_ENDPOINT_OUT
- #define USB_RECIP_ENDPOINT			LIBUSB_RECIPIENT_ENDPOINT
- #define USB_RECIP_INTERFACE		LIBUSB_RECIPIENT_INTERFACE
- #define USB_REQ_SET_DESCRIPTOR		LIBUSB_REQUEST_SET_DESCRIPTOR
- #define USB_TYPE_CLASS				LIBUSB_REQUEST_TYPE_CLASS
- #define USB_TYPE_VENDOR			LIBUSB_REQUEST_TYPE_VENDOR
+# define USB_CLASS_PER_INTERFACE	LIBUSB_CLASS_PER_INTERFACE
+# define USB_DT_STRING				LIBUSB_DT_STRING
+# define USB_ENDPOINT_IN			LIBUSB_ENDPOINT_IN
+# define USB_ENDPOINT_OUT			LIBUSB_ENDPOINT_OUT
+# define USB_RECIP_ENDPOINT			LIBUSB_RECIPIENT_ENDPOINT
+# define USB_RECIP_INTERFACE		LIBUSB_RECIPIENT_INTERFACE
+# define USB_REQ_SET_DESCRIPTOR		LIBUSB_REQUEST_SET_DESCRIPTOR
+# define USB_TYPE_CLASS				LIBUSB_REQUEST_TYPE_CLASS
+# define USB_TYPE_VENDOR			LIBUSB_REQUEST_TYPE_VENDOR
 
 /* Codebase updated to use LIBUSB_* tokens:
- #define ERROR_ACCESS		LIBUSB_ERROR_ACCESS
- #define ERROR_BUSY			LIBUSB_ERROR_BUSY
- #define ERROR_IO			LIBUSB_ERROR_IO
- #define ERROR_NO_DEVICE	LIBUSB_ERROR_NO_DEVICE
- #define ERROR_NOT_FOUND	LIBUSB_ERROR_NOT_FOUND
- #define ERROR_OVERFLOW		LIBUSB_ERROR_OVERFLOW
- #define ERROR_PIPE			LIBUSB_ERROR_PIPE
- #define ERROR_TIMEOUT		LIBUSB_ERROR_TIMEOUT
- #define ERROR_NO_MEM   LIBUSB_ERROR_NO_MEM
- #define ERROR_INVALID_PARAM  LIBUSB_ERROR_INVALID_PARAM
- #define ERROR_INTERRUPTED    LIBUSB_ERROR_INTERRUPTED
- #define ERROR_NOT_SUPPORTED  LIBUSB_ERROR_NOT_SUPPORTED
- #define ERROR_OTHER          LIBUSB_ERROR_OTHER
+# define ERROR_ACCESS		LIBUSB_ERROR_ACCESS
+# define ERROR_BUSY			LIBUSB_ERROR_BUSY
+# define ERROR_IO			LIBUSB_ERROR_IO
+# define ERROR_NO_DEVICE	LIBUSB_ERROR_NO_DEVICE
+# define ERROR_NOT_FOUND	LIBUSB_ERROR_NOT_FOUND
+# define ERROR_OVERFLOW		LIBUSB_ERROR_OVERFLOW
+# define ERROR_PIPE			LIBUSB_ERROR_PIPE
+# define ERROR_TIMEOUT		LIBUSB_ERROR_TIMEOUT
+# define ERROR_NO_MEM   LIBUSB_ERROR_NO_MEM
+# define ERROR_INVALID_PARAM  LIBUSB_ERROR_INVALID_PARAM
+# define ERROR_INTERRUPTED    LIBUSB_ERROR_INTERRUPTED
+# define ERROR_NOT_SUPPORTED  LIBUSB_ERROR_NOT_SUPPORTED
+# define ERROR_OTHER          LIBUSB_ERROR_OTHER
 */
 
  /* Functions, including range-checks to convert data types of the two APIs.
@@ -367,16 +373,16 @@
 #endif
 
  /* Functions for which simple mappings seem to suffice (no build warnings emitted): */
- #define usb_claim_interface	libusb_claim_interface
- #define usb_clear_halt			libusb_clear_halt
- #define usb_close				libusb_close
- #define usb_set_configuration	libusb_set_configuration
- #define usb_release_interface	libusb_release_interface
- #define usb_reset				libusb_reset_device
+# define usb_claim_interface	libusb_claim_interface
+# define usb_clear_halt			libusb_clear_halt
+# define usb_close				libusb_close
+# define usb_set_configuration	libusb_set_configuration
+# define usb_release_interface	libusb_release_interface
+# define usb_reset				libusb_reset_device
 
  /* FIXME: some original libusb1.c code cast the (int) argument
   * as (enum libusb_error) - should we force that in the macro? */
- #define nut_usb_strerror(a)	libusb_strerror(a)
+# define nut_usb_strerror(a)	libusb_strerror(a)
 #endif  /* WITH_LIBUSB_1_0 */
 
 /* Note: Checked above that in practice we handle some one libusb API */
@@ -400,70 +406,70 @@
  /* no typedef for usb_dev_handle - part of libusb-0.1 API names */
 
  typedef int usb_ctrl_requesttype;
- #define USB_CTRL_REQUESTTYPE_MIN	INT_MIN
- #define USB_CTRL_REQUESTTYPE_MAX	INT_MAX
+# define USB_CTRL_REQUESTTYPE_MIN	INT_MIN
+# define USB_CTRL_REQUESTTYPE_MAX	INT_MAX
 
  typedef int usb_ctrl_request;
- #define USB_CTRL_REQUEST_MIN	INT_MIN
- #define USB_CTRL_REQUEST_MAX	INT_MAX
+# define USB_CTRL_REQUEST_MIN	INT_MIN
+# define USB_CTRL_REQUEST_MAX	INT_MAX
 
  typedef int usb_ctrl_endpoint;
- #define USB_CTRL_ENDPOINT_MIN	INT_MIN
- #define USB_CTRL_ENDPOINT_MAX	INT_MAX
+# define USB_CTRL_ENDPOINT_MIN	INT_MIN
+# define USB_CTRL_ENDPOINT_MAX	INT_MAX
 
  typedef int usb_ctrl_msgvalue;
- #define USB_CTRL_MSGVALUE_MIN	INT_MIN
- #define USB_CTRL_MSGVALUE_MAX	INT_MAX
+# define USB_CTRL_MSGVALUE_MIN	INT_MIN
+# define USB_CTRL_MSGVALUE_MAX	INT_MAX
 
  typedef uint8_t usb_ctrl_cfgindex;
- #define USB_CTRL_CFGINDEX_MIN	0
- #define USB_CTRL_CFGINDEX_MAX	UINT8_MAX
+# define USB_CTRL_CFGINDEX_MIN	0
+# define USB_CTRL_CFGINDEX_MAX	UINT8_MAX
 
  typedef int usb_ctrl_repindex;
- #define USB_CTRL_REPINDEX_MIN	INT_MIN
- #define USB_CTRL_REPINDEX_MAX	INT_MAX
+# define USB_CTRL_REPINDEX_MIN	INT_MIN
+# define USB_CTRL_REPINDEX_MAX	INT_MAX
 
  typedef int usb_ctrl_strindex;
- #define USB_CTRL_STRINDEX_MIN	INT_MIN
- #define USB_CTRL_STRINDEX_MAX	INT_MAX
+# define USB_CTRL_STRINDEX_MIN	INT_MIN
+# define USB_CTRL_STRINDEX_MAX	INT_MAX
 
  typedef int usb_ctrl_descindex;
- #define USB_CTRL_DESCINDEX_MIN	INT_MIN
- #define USB_CTRL_DESCINDEX_MAX	INT_MAX
+# define USB_CTRL_DESCINDEX_MIN	INT_MIN
+# define USB_CTRL_DESCINDEX_MAX	INT_MAX
 
  /* Here MIN/MAX should not matter much, type mostly used for casting */
  typedef char* usb_ctrl_charbuf;
  typedef char usb_ctrl_char;
- #define USB_CTRL_CHAR_MIN	CHAR_MIN
- #define USB_CTRL_CHAR_MAX	CHAR_MAX
+# define USB_CTRL_CHAR_MIN	CHAR_MIN
+# define USB_CTRL_CHAR_MAX	CHAR_MAX
 
  typedef int usb_ctrl_charbufsize;
- #define USB_CTRL_CHARBUFSIZE_MIN	INT_MIN
- #define USB_CTRL_CHARBUFSIZE_MAX	INT_MAX
+# define USB_CTRL_CHARBUFSIZE_MIN	INT_MIN
+# define USB_CTRL_CHARBUFSIZE_MAX	INT_MAX
  /* There is no PRIi :) So we define directly by spec */
- #define PRI_NUT_USB_CTRL_CHARBUFSIZE "i"
+# define PRI_NUT_USB_CTRL_CHARBUFSIZE "i"
 
  typedef int usb_ctrl_timeout_msec;	/* in milliseconds */
- #define USB_CTRL_TIMEOUTMSEC_MIN	INT_MIN
- #define USB_CTRL_TIMEOUTMSEC_MAX	INT_MAX
+# define USB_CTRL_TIMEOUTMSEC_MIN	INT_MIN
+# define USB_CTRL_TIMEOUTMSEC_MAX	INT_MAX
 
  /* defines */
- #define LIBUSB_ERROR_ACCESS		-EACCES
- #define LIBUSB_ERROR_BUSY			-EBUSY
- #define LIBUSB_ERROR_IO			-EIO
- #define LIBUSB_ERROR_NO_DEVICE	-ENODEV
- #define LIBUSB_ERROR_NOT_FOUND	-ENOENT
- #define LIBUSB_ERROR_OVERFLOW		-EOVERFLOW
- #define LIBUSB_ERROR_PIPE			-EPIPE
- #define LIBUSB_ERROR_TIMEOUT		-ETIMEDOUT
- #define LIBUSB_ERROR_NO_MEM		-ENOMEM
- #define LIBUSB_ERROR_INVALID_PARAM		-EINVAL
- #define LIBUSB_ERROR_INTERRUPTED		-EINTR
- #define LIBUSB_ERROR_NOT_SUPPORTED	-ENOSYS
- #define LIBUSB_ERROR_OTHER		-ERANGE
+# define LIBUSB_ERROR_ACCESS		-EACCES
+# define LIBUSB_ERROR_BUSY			-EBUSY
+# define LIBUSB_ERROR_IO			-EIO
+# define LIBUSB_ERROR_NO_DEVICE	-ENODEV
+# define LIBUSB_ERROR_NOT_FOUND	-ENOENT
+# define LIBUSB_ERROR_OVERFLOW		-EOVERFLOW
+# define LIBUSB_ERROR_PIPE			-EPIPE
+# define LIBUSB_ERROR_TIMEOUT		-ETIMEDOUT
+# define LIBUSB_ERROR_NO_MEM		-ENOMEM
+# define LIBUSB_ERROR_INVALID_PARAM		-EINVAL
+# define LIBUSB_ERROR_INTERRUPTED		-EINTR
+# define LIBUSB_ERROR_NOT_SUPPORTED	-ENOSYS
+# define LIBUSB_ERROR_OTHER		-ERANGE
 
  /* Functions for which simple mappings seem to suffice (no build warnings emitted): */
- #define nut_usb_strerror(a)	usb_strerror()
+# define nut_usb_strerror(a)	usb_strerror()
 #endif  /* WITH_LIBUSB_0_1 */
 
 /* USB standard timeout [ms] */
@@ -554,4 +560,9 @@ void nut_usb_addvars(void);
  * here, to use in several USB-capable drivers. */
 void warn_if_bad_usb_port_filename(const char *fn);
 
+/* Retrieves string descriptor from device, decoded to 8-bit string,
+ * applies retries on failures, and assumes en_US in case the
+ * langid descriptor is invalid. */
+int nut_usb_get_string(usb_dev_handle *udev, int StringIdx, char *buf, size_t buflen);
+
 #endif /* NUT_USB_COMMON_H */
diff --git a/drivers/usbhid-ups.c b/drivers/usbhid-ups.c
index 4775d38fe8..b5968d0a02 100644
--- a/drivers/usbhid-ups.c
+++ b/drivers/usbhid-ups.c
@@ -6,6 +6,7 @@
  *   2005-2006 Peter Selinger <selinger@users.sourceforge.net>
  *   2007-2009 Arjen de Korte <adkorte-guest@alioth.debian.org>
  *   2016      Eaton / Arnaud Quette <ArnaudQuette@Eaton.com>
+ *   2020-2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  * This program was sponsored by MGE UPS SYSTEMS, and now Eaton
  *
@@ -28,7 +29,7 @@
  */
 
 #define DRIVER_NAME	"Generic HID driver"
-#define DRIVER_VERSION	"0.52"
+#define DRIVER_VERSION	"0.57"
 
 #define HU_VAR_WAITBEFORERECONNECT "waitbeforereconnect"
 
@@ -48,21 +49,21 @@
 
 #if !((defined SHUT_MODE) && SHUT_MODE)
 	/* explore stub goes first, others alphabetically */
-	#include "explore-hid.h"
-	#include "apc-hid.h"
-	#include "arduino-hid.h"
-	#include "belkin-hid.h"
-	#include "cps-hid.h"
-	#include "delta_ups-hid.h"
-	#include "ever-hid.h"
-	#include "idowell-hid.h"
-	#include "legrand-hid.h"
-	#include "liebert-hid.h"
-	#include "openups-hid.h"
-	#include "powercom-hid.h"
-	#include "powervar-hid.h"
-	#include "salicru-hid.h"
-	#include "tripplite-hid.h"
+#	include "explore-hid.h"
+#	include "apc-hid.h"
+#	include "arduino-hid.h"
+#	include "belkin-hid.h"
+#	include "cps-hid.h"
+#	include "delta_ups-hid.h"
+#	include "ever-hid.h"
+#	include "idowell-hid.h"
+#	include "legrand-hid.h"
+#	include "liebert-hid.h"
+#	include "openups-hid.h"
+#	include "powercom-hid.h"
+#	include "powervar-hid.h"
+#	include "salicru-hid.h"
+#	include "tripplite-hid.h"
 #endif	/* !SHUT_MODE => USB */
 
 /* Reference list of available subdrivers */
@@ -141,6 +142,15 @@ static size_t interrupt_pipe_EIO_count = 0; /* How many times we had I/O errors
 static time_t lastpoll; /* Timestamp the last polling */
 hid_dev_handle_t udev = HID_DEV_HANDLE_CLOSED;
 
+/**
+ * Track when calibration started, whether known from UPS status flags
+ * or interpreted from OL&DISCHRG combo on some devices (see below).
+ * The last_calibration_start is reset to 0 when the status becomes
+ * inactive, and last_calibration_finish is incremented every time.
+ */
+static time_t last_calibration_start = 0;
+static time_t last_calibration_finish = 0;
+
 /**
  * CyberPower UT series sometime need a bit of help deciding their online status.
  * This quirk is to enable the special handling of OL & DISCHRG at the same time
@@ -195,6 +205,34 @@ static int onlinedischarge_log_throttle_charge = -1;
  */
 static int onlinedischarge_log_throttle_hovercharge = 100;
 
+/**
+ * Per https://github.com/networkupstools/nut/issues/2347 some
+ * APC BXnnnnMI devices made (flashed?) in 2023-2024 irregularly
+ * but frequently spew a series of state changes:
+ * * (maybe OL+DISCHRG),
+ * * LB,
+ * * RB,
+ * * <all ok>
+ * within a couple of seconds. If this tunable is positive, we
+ * would only report the device states on the bus if they persist
+ * that long (or more), only then assuming they reflect a real
+ * problematic state and not some internal calibration.
+ */
+static int lbrb_log_delay_sec = 0;
+/**
+ * By default we only act on (lbrb_log_delay_sec>0) when the device
+ * is in calibration mode of whatever nature (directly reported or
+ * assumed from other flag combos). With this flag we do not check
+ * for calibration and only look at LB + RB timestamps.
+ */
+static int lbrb_log_delay_without_calibrating = 0;
+/**
+ * When did we last enter the situation? (if more than lbrb_log_delay_sec
+ * ago, then set the device status and emit the message)
+ */
+static time_t last_lb_start = 0;
+static time_t last_rb_start = 0;
+
 /* support functions */
 static hid_info_t *find_nut_info(const char *varname);
 static hid_info_t *find_hid_info(const HIDData_t *hiddata);
@@ -553,6 +591,22 @@ info_lkp_t divide_by_10_conversion[] = {
 	{ 0, NULL, divide_by_10_conversion_fun, NULL }
 };
 
+/* returns statically allocated string - must not use it again before
+   done with result! */
+static const char *divide_by_100_conversion_fun(double value)
+{
+       static char buf[20];
+
+       snprintf(buf, sizeof(buf), "%0.1f", value * 0.01);
+
+       return buf;
+}
+
+/* FIXME? Do we need an inverse "nuf()" here? */
+info_lkp_t divide_by_100_conversion[] = {
+       { 0, NULL, divide_by_100_conversion_fun, NULL }
+};
+
 /* returns statically allocated string - must not use it again before
    done with result! */
 static const char *kelvin_celsius_conversion_fun(double value)
@@ -997,10 +1051,19 @@ void upsdrv_makevartable(void)
 
 	addvar(VAR_VALUE, "onlinedischarge_log_throttle_hovercharge",
 		"Set to throttle log messages about discharging while online (only if battery.charge is under this value)");
-	
+
+	addvar(VAR_VALUE, "lbrb_log_delay_sec",
+		"Set to delay status-setting (and log messages) about device in LB or LB+RB state");
+
+	addvar(VAR_FLAG, "lbrb_log_delay_without_calibrating",
+		"Set to apply lbrb_log_delay_sec even if device is not calibrating");
+
 	addvar(VAR_FLAG, "disable_fix_report_desc",
 		"Set to disable fix-ups for broken USB encoding, etc. which we apply by default on certain vendors/products");
 
+	addvar(VAR_FLAG, "powercom_sdcmd_byte_order_fallback",
+		"Set to use legacy byte order for Powercom HID shutdown commands. Either it was wrong forever, or some older devices/firmwares had it the other way around");
+
 #if !((defined SHUT_MODE) && SHUT_MODE)
 	addvar(VAR_VALUE, "subdriver", "Explicit USB HID subdriver selection");
 
@@ -1047,9 +1110,9 @@ void upsdrv_updateinfo(void)
 
 		upsdebugx(1, "Got to reconnect!");
 		if (use_interrupt_pipe == TRUE && interrupt_pipe_EIO_count > 0) {
-			upsdebugx(0, "\nReconnecting. If you saw \"nut_libusb_get_interrupt: Input/Output Error\" "
+			upsdebugx(0, "Reconnecting. If you saw \"nut_libusb_get_interrupt: Input/Output Error\" "
 				"or similar message in the log above, try setting \"pollonly\" flag in \"ups.conf\" "
-				"options section for this driver!\n");
+				"options section for this driver!");
 		}
 
 		if (!reconnect_ups()) {
@@ -1332,6 +1395,105 @@ void upsdrv_initups(void)
 		}
 	}
 
+	val = getval("onlinedischarge_log_throttle_hovercharge");
+	if (val) {
+		int ipv = atoi(val);
+		if (ipv < 1 || ipv > 100) {
+			onlinedischarge_log_throttle_hovercharge = 100;
+			upslogx(LOG_WARNING,
+				"Warning: invalid value for "
+				"onlinedischarge_log_throttle_hovercharge: %s, "
+				"defaulting to %d",
+				val, onlinedischarge_log_throttle_hovercharge);
+		} else {
+			onlinedischarge_log_throttle_hovercharge = ipv;
+		}
+	}
+
+	val = getval("lbrb_log_delay_sec");
+	if (val) {
+		int ipv = atoi(val);
+		if ((ipv == 0 && strcmp("0", val)) || (ipv < 0)) {
+			lbrb_log_delay_sec = 3;
+			upslogx(LOG_WARNING,
+				"Warning: invalid value for "
+				"lbrb_log_delay_sec: %s, "
+				"defaulting to %d",
+				val, lbrb_log_delay_sec);
+		} else {
+			lbrb_log_delay_sec = ipv;
+		}
+	} else {
+		/* Activate APC BXnnnMI/BXnnnnMI tweaks, for details see
+		 * https://github.com/networkupstools/nut/issues/2347
+		 */
+		size_t	productLen = hd->Product ? strlen(hd->Product) : 0;
+
+		/* FIXME: Consider also ups.mfr.date as 2023 or newer?
+		 * Eventually up to some year this gets fixed?
+		 */
+		if (hd->Vendor
+		&&  productLen > 6	/* BXnnnMI at least */
+		&&  (!strcmp(hd->Vendor, "APC") || !strcmp(hd->Vendor, "American Power Conversion"))
+		&&  (strstr(hd->Product, " BX") || strstr(hd->Product, "BX") == hd->Product)
+		&&  (hd->Product[productLen - 2] == 'M' && hd->Product[productLen - 1] == 'I')
+		) {
+			int	got_lbrb_log_delay_without_calibrating = testvar("lbrb_log_delay_without_calibrating") ? 1 : 0,
+				got_onlinedischarge_calibration = testvar("onlinedischarge_calibration") ? 1 : 0,
+				got_onlinedischarge_log_throttle_sec = testvar("onlinedischarge_log_throttle_sec") ? 1 : 0;
+
+			lbrb_log_delay_sec = 3;
+
+			upslogx(LOG_INFO, "Defaulting lbrb_log_delay_sec=%d "
+				"for %s model %s%s%s%s%s%s%s%s%s%s",
+				lbrb_log_delay_sec,
+				hd->Vendor, hd->Product,
+
+				!got_lbrb_log_delay_without_calibrating
+				|| !got_onlinedischarge_calibration
+				|| !got_onlinedischarge_log_throttle_sec
+				? "; consider also setting the " : "",
+
+				!got_lbrb_log_delay_without_calibrating
+				? "lbrb_log_delay_without_calibrating " : "",
+
+				!got_lbrb_log_delay_without_calibrating
+				&& (!got_onlinedischarge_calibration
+				 || !got_onlinedischarge_log_throttle_sec)
+				? "and/or " : "",
+
+				!got_onlinedischarge_calibration
+				? "onlinedischarge_calibration " : "",
+
+				(!got_lbrb_log_delay_without_calibrating
+				|| !got_onlinedischarge_calibration )
+				&& !got_onlinedischarge_log_throttle_sec
+				? "and/or " : "",
+
+				!got_onlinedischarge_log_throttle_sec
+				? "onlinedischarge_log_throttle_sec " : "",
+
+				!got_lbrb_log_delay_without_calibrating
+				|| !got_onlinedischarge_calibration
+				|| !got_onlinedischarge_log_throttle_sec
+				? "flag" : "",
+
+				2 > ( got_lbrb_log_delay_without_calibrating
+				    + got_onlinedischarge_calibration
+				    + got_onlinedischarge_log_throttle_sec)
+				? "(s)" : "",
+
+				!got_lbrb_log_delay_without_calibrating
+				|| !got_onlinedischarge_calibration
+				|| !got_onlinedischarge_log_throttle_sec
+				? " in your configuration" : "");
+		}
+	}
+
+	if (testvar("lbrb_log_delay_without_calibrating")) {
+		lbrb_log_delay_without_calibrating = 1;
+	}
+
 	if (testvar("disable_fix_report_desc")) {
 		disable_fix_report_desc = 1;
 	}
@@ -1426,6 +1588,11 @@ void possibly_supported(const char *mfr, HIDDevice_t *arghd)
 "'-x productid=%04x' option. Please report your results to the NUT user's\n"
 "mailing list <nut-upsuser@lists.alioth.debian.org>.\n",
 	mfr, arghd->VendorID, arghd->ProductID, arghd->ProductID);
+
+	if (arghd->VendorID == 0x06da) {
+		upsdebugx(0,
+"Please note that this Vendor ID is also known in devices supported by nutdrv_qx");
+	}
 }
 
 /* Update ups_status to remember this status item. Interpretation is
@@ -1927,10 +2094,49 @@ unsigned ups_status_get(void)
 	return ups_status;
 }
 
+/** Helper to both status_set("CAL") and track last_calibration_start timestamp */
+static void status_set_CAL(void)
+{
+	/* Note: dstate tokens can only be set, not cleared; a
+	 * dstate_init() wipes the whole internal buffer though. */
+	int	wasSet = status_get("CAL");
+	time_t	now;
+
+	time(&now);
+
+	/* A few sanity checks */
+	if (wasSet) {
+		if (!last_calibration_start) {
+			upsdebugx(2, "%s: status was already set but not time-stamped: CAL", __func__);
+		} else {
+			upsdebugx(2, "%s: status was already set %f sec ago : CAL",
+				__func__, difftime(now, last_calibration_start));
+		}
+	} else {
+		if (last_calibration_finish) {
+			upsdebugx(2, "%s: starting a new calibration, last one finished %f sec ago",
+				__func__, difftime(now, last_calibration_finish));
+		} else {
+			upsdebugx(2, "%s: starting a new calibration, first in this driver's lifetime",
+				__func__);
+		}
+	}
+
+	if (!last_calibration_start) {
+		last_calibration_start = now;
+	}
+
+	if (!wasSet) {
+		status_set("CAL");		/* calibration */
+	}
+}
+
 /* Convert the local status information to NUT format and set NUT
    status. */
 static void ups_status_set(void)
 {
+	int	isCalibrating = 0;
+
 	if (ups_status & STATUS(VRANGE)) {
 		dstate_setinfo("input.transfer.reason", "input voltage out of range");
 	} else if (ups_status & STATUS(FRANGE)) {
@@ -1946,7 +2152,7 @@ static void ups_status_set(void)
 	 * raise FSD urgently. So we first let upsmon know it is just a drill.
 	 */
 	if (ups_status & STATUS(CALIB)) {
-		status_set("CAL");		/* calibration */
+		status_set_CAL();		/* calibration */
 	}
 
 	if ((!(ups_status & STATUS(DISCHRG))) && (
@@ -1954,8 +2160,8 @@ static void ups_status_set(void)
 		|| onlinedischarge_log_throttle_charge != -1
 	)) {
 		upsdebugx(1,
-			"%s: seems that UPS [%s] was in OL+DISCHRG state, "
-			"but no longer is now.",
+			"%s: seems that UPS [%s] was in OL+DISCHRG state "
+			"previously, but no is longer discharging now.",
 			__func__, upsname);
 		onlinedischarge_log_throttle_timestamp = 0;
 		onlinedischarge_log_throttle_charge = -1;
@@ -1969,7 +2175,7 @@ static void ups_status_set(void)
 		/* if online but discharging */
 		if (onlinedischarge_calibration) {
 			/* if we treat OL+DISCHRG as calibrating */
-			status_set("CAL");	/* calibration */
+			status_set_CAL();	/* calibration */
 		}
 
 		if (onlinedischarge_onbattery) {
@@ -1995,23 +2201,38 @@ static void ups_status_set(void)
 			/* First disable, then enable if OK for noise*/
 			do_logmsg = 0;
 
-			/* Time or not, did the charge change since last log? */
+			/* Time or not, did the charge change since last log?
+			 * Reminder: "onlinedischarge_log_throttle_charge" is
+			 * the last-reported charge in OL+DISCHRG situation,
+			 * as the battery remainder trickles down and we only
+			 * report the changes (throttling the message stream).
+			 * The "onlinedischarge_log_throttle_hovercharge" lets
+			 * us ignore sufficiently high battery charges, where
+			 * the user configuration (or defaults at 100%) tell
+			 * us this is just about the battery not accepting the
+			 * external power *all* the time so its charge "hovers"
+			 * (typically between 90%-100%) to benefit the chemical
+			 * process back-end of the battery and its life time.
+			 */
 			if ((s = dstate_getinfo("battery.charge"))) {
-				/* NOTE: "0" may mean a conversion error: */
+				/* NOTE: exact "0" may mean a conversion error: */
 				current_charge = atoi(s);
 				if (current_charge > 0
 				&&  current_charge != onlinedischarge_log_throttle_charge
 				) {
 					/* Charge has changed, but is it
 					 * now low enough to worry? */
-					if (onlinedischarge_log_throttle_hovercharge
-					    < onlinedischarge_log_throttle_charge
+					if (current_charge
+					    < onlinedischarge_log_throttle_hovercharge
 					) {
 						upsdebugx(3, "%s: current "
 							"battery.charge=%d is under "
-							"onlinedischarge_log_throttle_charge=%d",
+							"onlinedischarge_log_throttle_hovercharge=%d "
+							"(previous onlinedischarge_log_throttle_charge=%d): %s",
 							__func__, current_charge,
-							onlinedischarge_log_throttle_charge);
+							onlinedischarge_log_throttle_hovercharge,
+							onlinedischarge_log_throttle_charge,
+							(current_charge > onlinedischarge_log_throttle_charge ? "charging" : "draining"));
 						do_logmsg = 1;
 					} else {
 						/* All seems OK, don't spam log
@@ -2020,9 +2241,12 @@ static void ups_status_set(void)
 						upsdebugx(5, "%s: current "
 							"battery.charge=%d "
 							"is okay compared to "
-							"onlinedischarge_log_throttle_charge=%d",
+							"onlinedischarge_log_throttle_hovercharge=%d "
+							"(previous onlinedischarge_log_throttle_charge=%d): %s",
 							__func__, current_charge,
-							onlinedischarge_log_throttle_charge);
+							onlinedischarge_log_throttle_hovercharge,
+							onlinedischarge_log_throttle_charge,
+							(current_charge > onlinedischarge_log_throttle_charge ? "charging" : "draining"));
 					}
 				}
 			} else {
@@ -2057,6 +2281,7 @@ static void ups_status_set(void)
 		}
 
 		if (do_logmsg) {
+			/* If OL+DISCHRG, and not-throttled against log spam */
 			char	msg_charge[LARGEBUF];
 			msg_charge[0] = '\0';
 
@@ -2075,9 +2300,10 @@ static void ups_status_set(void)
 				} else {
 					snprintf(msg_charge, sizeof(msg_charge),
 						"Battery charge changed from %d to %d "
-						"since last such report. ",
+						"since last such report (%s). ",
 						onlinedischarge_log_throttle_charge,
-						current_charge);
+						current_charge,
+						(current_charge > onlinedischarge_log_throttle_charge ? "charging" : "draining"));
 				}
 				onlinedischarge_log_throttle_charge = current_charge;
 			}
@@ -2093,6 +2319,8 @@ static void ups_status_set(void)
 		status_set("OL");
 	}
 
+	isCalibrating = status_get("CAL");
+
 	if ((ups_status & STATUS(DISCHRG)) &&
 		!(ups_status & STATUS(DEPLETED))) {
 		status_set("DISCHRG");		/* discharging */
@@ -2102,13 +2330,58 @@ static void ups_status_set(void)
 		status_set("CHRG");		/* charging */
 	}
 	if (ups_status & (STATUS(LOWBATT) | STATUS(TIMELIMITEXP) | STATUS(SHUTDOWNIMM))) {
-		status_set("LB");		/* low battery */
+		if (lbrb_log_delay_sec < 1
+		|| (!isCalibrating && !lbrb_log_delay_without_calibrating)
+		|| !(ups_status & STATUS(ONLINE))	/* assume actual power failure, do not delay */
+		) {
+			/* Quick and easy decision */
+			status_set("LB");		/* low battery */
+		} else {
+			time_t	now;
+			time(&now);
+
+			if (!last_lb_start) {
+				last_lb_start = now;
+			} else {
+				if (difftime(now, last_lb_start) > lbrb_log_delay_sec) {
+					/* Patience expired */
+					status_set("LB");	/* low battery */
+				} else {
+					upsdebugx(2, "%s: throttling LB status due to lbrb_log_delay_sec", __func__);
+				}
+			}
+		}
+	} else {
+		last_lb_start = 0;
 	}
 	if (ups_status & STATUS(OVERLOAD)) {
 		status_set("OVER");		/* overload */
 	}
 	if (ups_status & STATUS(REPLACEBATT)) {
-		status_set("RB");		/* replace batt */
+		if (lbrb_log_delay_sec < 1
+		|| (!isCalibrating && !lbrb_log_delay_without_calibrating)
+		|| !last_lb_start	/* Calibration ended (not LB anymore) */
+		|| !(ups_status & STATUS(ONLINE))	/* assume actual power failure, do not delay */
+		) {
+			/* Quick and easy decision */
+			status_set("RB");		/* replace batt */
+		} else {
+			time_t	now;
+			time(&now);
+
+			if (!last_rb_start) {
+				last_rb_start = now;
+			} else {
+				if (difftime(now, last_rb_start) > lbrb_log_delay_sec) {
+					/* Patience expired */
+					status_set("RB");	/* replace batt */
+				} else {
+					upsdebugx(2, "%s: throttling RB status due to lbrb_log_delay_sec", __func__);
+				}
+			}
+		}
+	} else {
+		last_rb_start = 0;
 	}
 	if (ups_status & STATUS(TRIM)) {
 		status_set("TRIM");		/* SmartTrim */
@@ -2122,6 +2395,15 @@ static void ups_status_set(void)
 	if (ups_status & STATUS(OFF)) {
 		status_set("OFF");		/* ups is off */
 	}
+
+	if (!isCalibrating) {
+		if (last_calibration_start) {
+			time(&last_calibration_finish);
+			upsdebugx(2, "%s: calibration is no longer in place, took %f sec",
+				__func__, difftime(last_calibration_finish, last_calibration_start));
+		}
+		last_calibration_start = 0;
+	}
 }
 
 /* find info element definition in info array
diff --git a/drivers/usbhid-ups.h b/drivers/usbhid-ups.h
index 2e8a3fcedd..f6f67fea72 100644
--- a/drivers/usbhid-ups.h
+++ b/drivers/usbhid-ups.h
@@ -26,11 +26,19 @@
 #ifndef USBHID_UPS_H
 #define USBHID_UPS_H
 
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include "config.h"
+
 #include "libhid.h"
 
 extern hid_dev_handle_t	udev;
@@ -114,6 +122,7 @@ extern info_lkp_t date_conversion[];
 extern info_lkp_t hex_conversion[];
 extern info_lkp_t stringid_conversion[];
 extern info_lkp_t divide_by_10_conversion[];
+extern info_lkp_t divide_by_100_conversion[];
 extern info_lkp_t kelvin_celsius_conversion[];
 
 /* ---------------------------------------------------------------------- */
diff --git a/drivers/victronups.c b/drivers/victronups.c
index 49901f43bf..ad11b4b3cb 100644
--- a/drivers/victronups.c
+++ b/drivers/victronups.c
@@ -32,7 +32,7 @@
 #include "serial.h"
 
 #define DRIVER_NAME	"GE/IMV/Victron UPS driver"
-#define DRIVER_VERSION	"0.22"
+#define DRIVER_VERSION	"0.23"
 
 /* driver description structure */
 upsdrv_info_t upsdrv_info = {
diff --git a/include/Makefile.am b/include/Makefile.am
index 90c2dbc54b..cb13105ac5 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -3,15 +3,17 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
-
-dist_noinst_HEADERS = attribute.h common.h extstate.h proto.h			\
-    state.h str.h timehead.h upsconf.h nut_float.h nut_stdint.h nut_platform.h	\
-    nutstream.hpp nutwriter.hpp nutipc.hpp nutconf.hpp \
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
+
+dist_noinst_HEADERS = \
+    attribute.h common.h extstate.h proto.h			\
+    state.h str.h timehead.h upsconf.h				\
+    nut_bool.h nut_float.h nut_stdint.h nut_platform.h		\
+    nutstream.hpp nutwriter.hpp nutipc.hpp nutconf.hpp		\
     wincompat.h
 
 # Optionally deliverable as part of NUT public API:
@@ -30,7 +32,9 @@ MAINTAINERCLEANFILES = Makefile.in .dirstamp
 # (for builds not made from the tagged commit in a Git workspace)
 
 nut_version.h: @FORCE_NUT_VERSION@
-	@GITREV="`git describe --tags --match 'v[0-9]*.[0-9]*.[0-9]' --exclude '*-signed' --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*' 2>/dev/null | sed -e 's/^v\([0-9]\)/\1/' -e 's,^.*/,,'`" || GITREV=""; \
+	@GITREV="`$(top_srcdir)/tools/gitlog2version.sh`" || GITREV=""; \
+	 GITREV_IS_RELEASE="`NUT_VERSION_QUERY=IS_RELEASE $(top_srcdir)/tools/gitlog2version.sh 2>/dev/null`" || GITREV_IS_RELEASE="false"; \
+	 GITREV_SEMVER="`NUT_VERSION_QUERY=SEMVER $(top_srcdir)/tools/gitlog2version.sh 2>/dev/null`" || GITREV_SEMVER=""; \
 	 {  echo '/* Autogenerated file. Do not change. */' ; \
 	    echo '/* This file was generated by "make". */' ; \
 	    if [ -z "$$GITREV" ]; then \
@@ -43,9 +47,18 @@ nut_version.h: @FORCE_NUT_VERSION@
 	        echo ' * building the newest tagged commit itself - then just the tag).'; \
 	        echo ' */'  ; \
 	    fi ; \
+	    if [ -z "$$GITREV_SEMVER" ]; then \
+	        GITREV_SEMVER="@NUT_SOURCE_GITREV_SEMVER@"; \
+	    fi ; \
 	    echo "#define NUT_VERSION_MACRO \"$$NUT_VERSION\"" ; \
+	    echo "#define NUT_VERSION_SEMVER_MACRO \"$$GITREV_SEMVER\"" ; \
+	    if $$GITREV_IS_RELEASE ; then \
+	        echo "#define NUT_VERSION_IS_RELEASE 1" ; \
+	    else \
+	        echo "#define NUT_VERSION_IS_RELEASE 0" ; \
+	    fi ; \
 	 } > "$@.tmp" ; \
-	 echo "NUT_VERSION: \"$$NUT_VERSION\""
+	 echo "NUT_VERSION: \"$$NUT_VERSION\"  NUT_VERSION_IS_RELEASE:$$GITREV_IS_RELEASE  NUT_VERSION_SEMVER: \"$$GITREV_SEMVER\""
 	-test -f "$@" || cp "$@.tmp" "$@"
 	-cmp -s "$@.tmp" "$@" || cp "$@.tmp" "$@"
 	-rm -f "$@.tmp"
diff --git a/include/common.h b/include/common.h
index 407b8425aa..1a1c3a8188 100644
--- a/include/common.h
+++ b/include/common.h
@@ -1,6 +1,7 @@
 /* common.h - prototypes for the common useful functions
 
    Copyright (C) 2000  Russell Kroll <rkroll@exploits.org>
+   Copyright (C) 2021-2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,7 +21,13 @@
 #ifndef NUT_COMMON_H_SEEN
 #define NUT_COMMON_H_SEEN 1
 
-#include "config.h"		/* must be the first header */
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #ifdef WIN32
 # ifndef __POSIX_VISIBLE
@@ -193,6 +200,42 @@ extern const char *UPS_VERSION;
 /** @brief Default timeout (in seconds) for retrieving the result of a `TRACKING`-enabled operation (e.g. `INSTCMD`, `SET VAR`). */
 #define DEFAULT_TRACKING_TIMEOUT	10
 
+/* Returns a pointer to static internal char[] buffer with current value
+ * of NUT_VERSION_MACRO (aka char* UPS_VERSION) and its layman description
+ * (e.g. a "release" or "development iteration after" a certain semantically
+ * versioned release). Returns UPS_VERSION if failed to construct a better
+ * description. Either way, should not be free()'d by caller and does not
+ * have an end-of-line char of its own. */
+const char *describe_NUT_VERSION_once(void);
+
+/* Based on NUT_QUIET_INIT_BANNER envvar (present and empty or "true")
+ * hide the NUT tool name+version banners; show them by default */
+int banner_is_disabled(void);
+
+/* Some NUT programs have historically printed their banner at start-up
+ * always, and so did not print one in help()/usage() or handling `-V`
+ * like others did. Now that we have NUT_QUIET_INIT_BANNER, we need a
+ * way to print that banner (regardless of the flag in some cases).
+ * The "even_if_disabled" should be 0 for initial banner of those
+ * programs (so the envvar would hide it), 1 -V case and 2 in -h case
+ * (for a blank line after). As before, the banner is printed to stdout.
+ * Returns the result of printf() involved. Remembers to not print again
+ * if the earlier printf() was successful.
+ */
+int print_banner_once(const char *prog, int even_if_disabled);
+
+/* Normally we can (attempt to) use the syslog or Event Log (WIN32),
+ * but environment variable NUT_DEBUG_SYSLOG allows to bypass it, and
+ * perhaps keep daemons logging to stderr (e.g. in NUT Integration Test
+ * suite to not pollute the OS logs, or in systemd where stderr and
+ * syslog both go into the same journal). Returns:
+ *  0  Not disabled (NUT_DEBUG_SYSLOG not set to a value below; unset or "default"
+ *     values are handled quietly, but others emit a warning)
+ *  1  Disabled and background() keeps stderr attached (NUT_DEBUG_SYSLOG="stderr")
+ *  2  Disabled and background() detaches stderr as usual (NUT_DEBUG_SYSLOG="none")
+ */
+int syslog_is_disabled(void);
+
 /* get the syslog ready for us */
 void open_syslog(const char *progname);
 
@@ -208,6 +251,46 @@ void become_user(struct passwd *pw);
 /* drop down into a directory and throw away pointers to the old path */
 void chroot_start(const char *path);
 
+/* Try to identify process (program) name for the given PID,
+ * return NULL if we can not for any reason (does not run,
+ * no rights, do not know how to get it on current OS, etc.)
+ * If the returned value is not NULL, caller should free() it.
+ * Some implementation pieces borrowed from
+ * https://man7.org/linux/man-pages/man2/readlink.2.html and
+ * https://github.com/openbsd/src/blob/master/bin/ps/ps.c
+ * NOTE: Very much platform-dependent! */
+char * getprocname(pid_t pid);
+
+/* Determine the base name of specified progname (may be full path)
+ * and the location of the last "." dot character in it for extension
+ * (caller's len and dot populated only if pointers are not NULL).
+ */
+size_t parseprogbasename(char *buf, size_t buflen, const char *progname, size_t *pprogbasenamelen, size_t *pprogbasenamedot);
+
+/* If we can determine the binary path name of the specified "pid",
+ * check if it matches the assumed name of the current program.
+ * Returns:
+ *	-3	Skipped because NUT_IGNORE_CHECKPROCNAME is set
+ *	-2	Could not parse a program name (ok to proceed,
+ *		risky - but matches legacy behavior)
+ *	-1	Could not identify a program name (ok to proceed,
+ *		risky - but matches legacy behavior)
+ *	0	Process name identified, does not seem to match
+ *	1+	Process name identified, and seems to match with
+ *		varying precision
+ * Generally speaking, if (checkprocname(...)) then ok to proceed
+ */
+int checkprocname(pid_t pid, const char *progname);
+/* compareprocname() does the bulk of work for checkprocname()
+ * and returns same values. The "pid" argument is used for logging.
+ * Generally speaking, if (compareprocname(...)) then ok to proceed
+ */
+int compareprocname(pid_t pid, const char *procname, const char *progname);
+/* Helper for the above methods and some others. If it returns true (1),
+ * work about PID-name comparison should be quickly skipped.
+ */
+int checkprocname_ignored(const char *caller);
+
 /* write a pid file - <name> is a full pathname *or* just the program name */
 void writepid(const char *name);
 
@@ -215,11 +298,11 @@ void writepid(const char *name);
  * a few sanity checks; returns -1 on error */
 pid_t parsepid(const char *buf);
 
-/* send a signal to another running process */
+/* send a signal to another running NUT process */
 #ifndef WIN32
-int sendsignal(const char *progname, int sig);
+int sendsignal(const char *progname, int sig, int check_current_progname);
 #else
-int sendsignal(const char *progname, const char * sig);
+int sendsignal(const char *progname, const char * sig, int check_current_progname);
 #endif
 
 int snprintfcat(char *dst, size_t size, const char *fmt, ...)
@@ -230,20 +313,34 @@ pid_t get_max_pid_t(void);
 
 /* send sig to pid after some sanity checks, returns
  * -1 for error, or zero for a successfully sent signal */
-int sendsignalpid(pid_t pid, int sig);
+int sendsignalpid(pid_t pid, int sig, const char *progname, int check_current_progname);
+
+/* open <pidfn> and get the pid
+ * returns zero or more for successfully retrieved value,
+ * negative for errors:
+ * -3   PID file not found
+ * -2   PID file not parsable
+ */
+pid_t parsepidfile(const char *pidfn);
 
-/* open <pidfn>, get the pid, then send it <sig>
+#ifndef WIN32
+/* use parsepidfile() to get the pid, then send it <sig>
  * returns zero for successfully sent signal,
  * negative for errors:
  * -3   PID file not found
  * -2   PID file not parsable
  * -1   Error sending signal
+ *
+ * if executable process with that pid has suitable progname
+ * (specified or that of the current process, depending on args:
+ * most daemons request to check_current_progname for their other
+ * process instancees, but upsdrvctl which manages differently
+ * named driver programs does not request it)
  */
-#ifndef WIN32
-/* open <pidfn>, get the pid, then send it <sig> */
-int sendsignalfn(const char *pidfn, int sig);
+int sendsignalfn(const char *pidfn, int sig, const char *progname, int check_current_progname);
 #else
-int sendsignalfn(const char *pidfn, const char * sig);
+/* No progname here - communications via named pipe */
+int sendsignalfn(const char *pidfn, const char * sig, const char *progname_ignored, int check_current_progname_ignored);
 #endif
 
 const char *xbasename(const char *file);
@@ -258,12 +355,40 @@ const char * confpath(void);
 /* Return the default path for the directory containing state files */
 const char * dflt_statepath(void);
 
-/* Return the alternate path for pid files */
+/* Return the alternate path for pid files (non-root daemons) */
 const char * altpidpath(void);
 
+/* Return the main path for pid files (root daemons like upsmon) */
+const char * rootpidpath(void);
+
 /* Die with a standard message if socket filename is too long */
 void check_unix_socket_filename(const char *fn);
 
+/* Provide integration for systemd inhibitor interface (where available,
+ * dummy code otherwise) implementing the pseudo-code example from
+ * https://systemd.io/INHIBITOR_LOCKS/
+ * TODO: Potentially extensible to other frameworks with similar concepts?..
+ */
+TYPE_FD Inhibit(const char *arg_what, const char *arg_who, const char *arg_why, const char *arg_mode);
+/* Let the service management framework proceed with its sleep mode */
+void Uninhibit(TYPE_FD *fd_ptr);
+/* Check once if the system plans to sleep or is waking up:
+ *  -1	Same reply as before, whatever it was
+ *   0	(false) Just after the sleep, at least as a bus signal
+ *   1	(true) Before the sleep - we must process and un-block it
+ */
+int isPreparingForSleep(void);
+
+/* A couple of methods to reflect built-in (absent) or run-time (it depends)
+ * support for monitoring that the OS goes to sleep and wakes up, and if we
+ * can "inhibit" that going to sleep in order to do some house-keeping first.
+ * -1 = do not know yet
+ *  0 = not supported, do not bother asking in daemon loops
+ *  1 = seems supported
+ */
+int isInhibitSupported(void);
+int isPreparingForSleepSupported(void);
+
 /* Send (daemon) state-change notifications to an
  * external service management framework such as systemd.
  * State types below are initially loosely modeled after
@@ -341,6 +466,13 @@ void nut_report_config_flags(void);
 void upsdebugx_report_search_paths(int level, int report_search_paths_builtin);
 void nut_prepare_search_paths(void);
 
+/* Internal toggle for some NUT programs that deal with signal sending.
+ * For a detailed rationale comment see common.c */
+extern int nut_sendsignal_debug_level;
+#define NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT 6
+#define NUT_SENDSIGNAL_DEBUG_LEVEL_FOPEN_PIDFILE 5
+#define NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING 4
+
 extern int nut_debug_level;
 extern int nut_log_level;
 
diff --git a/include/nut_bool.h b/include/nut_bool.h
new file mode 100644
index 0000000000..0fa4b41828
--- /dev/null
+++ b/include/nut_bool.h
@@ -0,0 +1,99 @@
+/*
+ * nut_bool.h - Network UPS Tools boolean type definitions
+ *              which should ensure a "nut_bool_t" name with
+ *              lower-case values "true" and "false"
+ *
+ * Inspired by earlier efforts and numerous definitions in NUT codebase.
+ * Copyright (C) 2024 Jim Klimov <jimklimov+nut@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef NUT_BOOL_H_SEEN
+#define NUT_BOOL_H_SEEN 1
+
+#ifdef __cplusplus
+/* *INDENT-OFF* */
+extern "C" {
+/* *INDENT-ON* */
+#endif
+
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
+
+/* See also https://en.cppreference.com/w/cpp/header/cstdbool for more
+ * info about what should be available where per standard approach. */
+#ifdef __cplusplus
+# if defined HAVE_CSTDBOOL_H || defined HAVE_CSTDBOOL
+#  include <cstdbool>
+# else
+#  ifdef HAVE_STDBOOL_H
+#   include <stdbool.h>
+#  endif
+# endif
+#else
+/* plain C */
+#  ifdef HAVE_STDBOOL_H
+#   include <stdbool.h>
+#  endif
+#endif
+
+/* Is the goal achieved by the system headers or compiler itself,
+ * so we can just alias to existing type and its values? */
+#if defined __bool_true_false_are_defined && __bool_true_false_are_defined
+	typedef bool nut_bool_t;
+#elif defined FOUND__BOOL_TYPE && defined HAVE__BOOL_VALUE_LOWERCASE
+	typedef FOUND__BOOL_TYPE nut_bool_t;
+#elif defined FOUND_BOOL_TYPE && defined HAVE_BOOL_VALUE_LOWERCASE
+	typedef FOUND_BOOL_TYPE nut_bool_t;
+#elif defined FOUND_BOOLEAN_TYPE && defined HAVE_BOOLEAN_VALUE_LOWERCASE
+	typedef FOUND_BOOLEAN_TYPE nut_bool_t;
+#elif defined FOUND_BOOL_T_TYPE && defined HAVE_BOOL_T_VALUE_LOWERCASE
+	typedef FOUND_BOOL_T_TYPE nut_bool_t;
+#else
+	/* Need a new type; can we use an enum with lower-case values? */
+# if (defined true && defined false) || defined HAVE__BOOL_VALUE_LOWERCASE || defined HAVE_BOOL_VALUE_LOWERCASE || defined HAVE_BOOLEAN_VALUE_LOWERCASE || defined HAVE_BOOL_T_VALUE_LOWERCASE
+	/* Lower-case true/false are known */
+#  if defined FOUND__BOOL_TYPE
+	/* Got a C99 built-in mandated by the standard */
+	typedef FOUND__BOOL_TYPE nut_bool_t;
+#  else
+	typedef int nut_bool_t;
+#  endif
+# elif defined FOUND__BOOL_VALUE_TRUE && defined FOUND__BOOL_VALUE_FALSE
+	typedef enum nut_bool_enum { false = FOUND__BOOL_VALUE_FALSE, true = FOUND__BOOL_VALUE_TRUE } nut_bool_t;
+# elif defined FOUND_BOOL_VALUE_TRUE && defined FOUND_BOOL_VALUE_FALSE
+	typedef enum nut_bool_enum { false = FOUND_BOOL_VALUE_FALSE, true = FOUND_BOOL_VALUE_TRUE } nut_bool_t;
+# elif defined FOUND_BOOLEAN_VALUE_TRUE && defined FOUND_BOOLEAN_VALUE_FALSE
+	typedef enum nut_bool_enum { false = FOUND_BOOLEAN_VALUE_FALSE, true = FOUND_BOOLEAN_VALUE_TRUE } nut_bool_t;
+# elif defined FOUND_BOOL_T_VALUE_TRUE && defined FOUND_BOOL_T_VALUE_FALSE
+	typedef enum nut_bool_enum { false = FOUND_BOOL_T_VALUE_FALSE, true = FOUND_BOOL_T_VALUE_TRUE } nut_bool_t;
+# else
+	typedef enum nut_bool_enum { false = 0, true = 1 } nut_bool_t;
+# endif
+#endif
+
+#ifdef __cplusplus
+/* *INDENT-OFF* */
+}
+/* *INDENT-ON* */
+#endif
+
+#endif	/* NUT_BOOL_H_SEEN */
diff --git a/include/nut_float.h b/include/nut_float.h
index 290edb4909..fe790e6e99 100644
--- a/include/nut_float.h
+++ b/include/nut_float.h
@@ -22,7 +22,13 @@
 #ifndef NUT_FLOAT_H_SEEN
 #define NUT_FLOAT_H_SEEN 1
 
-#include "config.h"
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #if defined HAVE_FLOAT_H
 #  include <float.h>
@@ -51,4 +57,9 @@
 #define d_equal(x, y) ( fabs((double)(x) - (double)(y)) <= DBL_EPSILON )
 #define ld_equal(x, y) ( fabsl((long double)(x) - (long double)(y)) <= LDBL_EPSILON )
 
+#ifndef HAVE_STRTOF
+/* Use fallback from libcommon */
+float strtof(const char *nptr, char **endptr);
+#endif
+
 #endif	/* NUT_FLOAT_H_SEEN */
diff --git a/include/nut_platform.h b/include/nut_platform.h
index ba640c5a7c..90237d2600 100644
--- a/include/nut_platform.h
+++ b/include/nut_platform.h
@@ -27,26 +27,31 @@
 /* Apple Mac OS X, iOS and Darwin */
 #if (defined __APPLE__ && defined __MACH__)
 	/** Apple OS based on Mach ukernel */
-	#define NUT_PLATFORM_APPLE_MACH
+#	define NUT_PLATFORM_APPLE_MACH
 
-	#include <TargetConditionals.h>
+	/* https://stackoverflow.com/a/2339910/4715872 */
+#	ifndef SOEXT
+#		define SOEXT ".dylib"
+#	endif
 
-	#if (defined TARGET_OS_EMBEDDED)
+#	include <TargetConditionals.h>
+
+#	if (defined TARGET_OS_EMBEDDED)
 		/** iOS (implies \ref NUT_PLATFORM_APPLE_MACH) */
-		#define NUT_PLATFORM_APPLE_IOS
-	#endif
-	#if (defined TARGET_IPHONE_SIMULATOR)
+#		define NUT_PLATFORM_APPLE_IOS
+#	endif
+#	if (defined TARGET_IPHONE_SIMULATOR)
 		/** iOS simulator (implies \ref NUT_PLATFORM_APPLE_MACH) */
-		#define NUT_PLATFORM_APPLE_IOS_SIMULATOR
-	#endif
-	#if (defined TARGET_OS_IPHONE)
+#		define NUT_PLATFORM_APPLE_IOS_SIMULATOR
+#	endif
+#	if (defined TARGET_OS_IPHONE)
 		/** iPhone (implies \ref NUT_PLATFORM_APPLE_MACH) */
-		#define NUT_PLATFORM_APPLE_IPHONE
-	#endif
-	#if (defined TARGET_OS_MAC)
+#		define NUT_PLATFORM_APPLE_IPHONE
+#	endif
+#	if (defined TARGET_OS_MAC)
 		/** Mac OS X (implies \ref NUT_PLATFORM_APPLE_MACH) */
-		#define NUT_PLATFORM_APPLE_OSX
-	#endif
+#		define NUT_PLATFORM_APPLE_OSX
+#	endif
 #endif
 
 /*
@@ -56,69 +61,94 @@
  * Remove if no longer necessary
  */
 #if (defined _AIX && !defined __unix__)
-	#define __unix__
+#	define __unix__
 #endif
 
 /* Microsoft Windows */
 #if (defined _WIN32 || defined _WIN64)
 	/** Windows */
-	#define NUT_PLATFORM_MS_WINDOWS
+#	define NUT_PLATFORM_MS_WINDOWS
+
+#	ifndef SOEXT
+#		define SOEXT ".dll"
+#	endif
 
-	#if (defined NTDDI_WIN8 && NTDDI_VERSION >= NTDDI_WIN8)
+#	if (defined NTDDI_WIN8 && NTDDI_VERSION >= NTDDI_WIN8)
 		/** Windows 8 */
-		#define NUT_PLATFORM_MS_WINDOWS8
-	#endif
+#		define NUT_PLATFORM_MS_WINDOWS8
+#	endif
 
 /* UNIX */
 /* Note that Apple OSX doesn't define __unix__ nor __unix; are they ashamed or something? */
 #elif (defined __unix__ || defined __unix || defined NUT_PLATFORM_APPLE_MACH)
-	#include <sys/param.h>
-	#include <unistd.h>
+#	include <sys/param.h>
+#	include <unistd.h>
 
 	/** UNIX */
-	#define NUT_PLATFORM_UNIX
+#	define NUT_PLATFORM_UNIX
 
-	#if (defined _POSIX_VERSION)
+#	if (defined _POSIX_VERSION)
 		/** POSIX (implies \ref NUT_PLATFORM_UNIX), expands to POSIX version */
-		#define NUT_PLATFORM_POSIX _POSIX_VERSION
-	#endif
+#		define NUT_PLATFORM_POSIX _POSIX_VERSION
+#	endif
 
-	#if (defined __linux__)
+#	if (defined __linux__)
 		/** Linux (implies \ref NUT_PLATFORM_UNIX) */
-		#define NUT_PLATFORM_LINUX
-	#endif
-	#if (defined __sun && defined __SVR4)
+#		define NUT_PLATFORM_LINUX
+#	endif
+#	if (defined __sun && defined __SVR4)
 		/** Solaris (implies \ref NUT_PLATFORM_UNIX) */
-		#define NUT_PLATFORM_SOLARIS
-	#endif
-	#if (defined __hpux)
+#		define NUT_PLATFORM_SOLARIS
+#	endif
+#	if (defined __hpux)
 		/** Hewlett-Packard HP-UX (implies \ref NUT_PLATFORM_UNIX) */
-		#define NUT_PLATFORM_HPUX
-	#endif
-	#if (defined _AIX)
+#		define NUT_PLATFORM_HPUX
+
+		/* Note: depending on CPU arch and OS version, library file
+		 * name patterns here could have been "*.so" as well.
+		 * E.g. per
+		 * https://community.hpe.com/t5/operating-system-hp-ux/so-and-sl-files/td-p/3780528
+		 *   *.sl are used in PA-RISC (11.11)
+		 *   *.so shared libraries are used in HP-UX 11.20 and upwards.
+		 * Integrity (Itanium-based) HPUX can use *.sl as well,
+		 * but it is not recommended, see ld(1) under -lx:
+		 *   https://web.archive.org/web/20090925153446/http://docs.hp.com/en/B2355-60103/ld.1.html
+		 */
+		/* FIXME: May want to detect better the CPU or OS version
+		 *  to decide the SOEXT here*/
+#		ifndef SOEXT
+#			define SOEXT ".sl"
+#		endif
+#	endif
+#	if (defined _AIX)
 		/** AIX (implies \ref NUT_PLATFORM_UNIX) */
-		#define NUT_PLATFORM_AIX
-	#endif
+#		define NUT_PLATFORM_AIX
+#	endif
 
 	/* Note that BSD is defined in sys/param.h */
-	#if (defined BSD)
+#	if (defined BSD)
 		/** BSD (implies \ref NUT_PLATFORM_UNIX) */
-		#define NUT_PLATFORM_BSD
+#		define NUT_PLATFORM_BSD
 
-		#if (defined __DragonFly__)
+#		if (defined __DragonFly__)
 			/** DragonFly (implies \ref NUT_PLATFORM_UNIX, \ref NUT_PLATFORM_BSD) */
-			#define NUT_PLATFORM_DRAGONFLY
-		#elif (defined __FreeBSD__)
+#			define NUT_PLATFORM_DRAGONFLY
+#		elif (defined __FreeBSD__)
 			/** FreeBSD (implies \ref NUT_PLATFORM_UNIX, \ref NUT_PLATFORM_BSD) */
-			#define NUT_PLATFORM_FREEBSD
-		#elif (defined __OpenBSD__)
+#			define NUT_PLATFORM_FREEBSD
+#		elif (defined __OpenBSD__)
 			/** OpenBSD (implies \ref NUT_PLATFORM_UNIX, \ref NUT_PLATFORM_BSD) */
-			#define NUT_PLATFORM_OPENBSD
-		#elif (defined __NetBSD__)
+#			define NUT_PLATFORM_OPENBSD
+#		elif (defined __NetBSD__)
 			/** NetBSD (implies \ref NUT_PLATFORM_UNIX, \ref NUT_PLATFORM_BSD) */
-			#define NUT_PLATFORM_NETBSD
-		#endif
-	#endif
+#			define NUT_PLATFORM_NETBSD
+#		endif
+#	endif
+#endif
+
+/* not WIN32, not MACOS, not HPUX... */
+#ifndef SOEXT
+#	define SOEXT ".so"
 #endif
 
 #endif  /* NUT_PLATFORM_H_SEEN */
diff --git a/include/nut_stdint.h b/include/nut_stdint.h
index 5f173191ae..9d64a061b4 100644
--- a/include/nut_stdint.h
+++ b/include/nut_stdint.h
@@ -21,7 +21,13 @@
 #ifndef NUT_STDINT_H_SEEN
 #define NUT_STDINT_H_SEEN 1
 
-#include "config.h"
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #ifndef __STDC_LIMIT_MACROS
 #define __STDC_LIMIT_MACROS 1
diff --git a/include/nutconf.hpp b/include/nutconf.hpp
index 086db17e23..02c50f271d 100644
--- a/include/nutconf.hpp
+++ b/include/nutconf.hpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
 	2012	Emilien Kia <emilien.kia@gmail.com>
+	2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -34,6 +35,7 @@
 #include <list>
 #include <map>
 #include <stdexcept>
+#include <typeinfo>
 
 /* See include/common.h for details behind this */
 #ifndef NUT_UNUSED_VARIABLE
@@ -61,6 +63,14 @@ class Settable
 protected:
 	Type _value;
 	bool _set;
+	std::string errMsg_ENOTSET()const {
+		static const std::string msg =
+			"Can not retrieve a Settable value of "
+			"an instance that was not assigned yet "
+			"(or was last known cleared)";
+		return msg;
+	}
+
 public:
 	Settable():_set(false){}
 	Settable(const Settable<Type>& val):_value(val._value), _set(val._set){}
@@ -74,11 +84,43 @@ class Settable
 	bool set()const{return _set;}
 	void clear(){_set = false;}
 
-	operator const Type&()const{return _value;}
-	operator Type&(){return _value;}
+	operator const Type&()const
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (!set())
+			throw std::invalid_argument(errMsg_ENOTSET());
+		return _value;
+	}
+	operator Type&()
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (!set())
+			throw std::invalid_argument(errMsg_ENOTSET());
+		return _value;
+	}
 
-	const Type& operator *()const{return _value;}
-	Type& operator *(){return _value;}
+	const Type& operator *()const
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (!set())
+			throw std::invalid_argument(errMsg_ENOTSET());
+		return _value;
+	}
+	Type& operator *()
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (!set())
+			throw std::invalid_argument(errMsg_ENOTSET());
+		return _value;
+	}
 
 	Settable<Type>& operator=(const Type& val){_value = val; _set = true; return *this;}
 
@@ -142,6 +184,417 @@ class Serialisable
 };  // end of class Serialisable
 
 
+/**
+ * \brief	Mix a boolean (yes/no) or wider integer range
+ */
+class BoolInt
+{
+private:
+	Settable<bool> b;
+	Settable<int>  i;
+
+public:
+	/** If set, its value specifies if we want i==0/1 to mean false/true
+	 *  in value-equality and type-cast operators for int and bool types.
+	 *  NOTE: If true, assignment from "0" and "1" strings sets the int
+	 *  not bool stored value representation!
+	 *  NOTE: Survives the clear() call which applies to stored value,
+	 *  but would be reset by assignment from another BoolInt object.
+	 */
+	Settable<bool> bool01;
+
+	/** Leave all contents un-set */
+	BoolInt() {}
+
+	BoolInt(const bool val) {
+		*this = val;
+	}
+	BoolInt(const bool val, bool newBool01) {
+		this->bool01 = newBool01;
+		*this = val;
+	}
+
+	BoolInt(const int val) {
+		*this = val;
+	}
+	BoolInt(const int val, bool newBool01) {
+		this->bool01 = newBool01;
+		*this = val;
+	}
+
+	BoolInt(const char* val) {
+		*this = val;
+	}
+	BoolInt(const char* val, bool newBool01) {
+		this->bool01 = newBool01;
+		*this = val;
+	}
+
+	BoolInt(const std::string &val) {
+		*this = val;
+	}
+	BoolInt(const std::string &val, bool newBool01) {
+		this->bool01 = newBool01;
+		*this = val;
+	}
+
+	BoolInt(const BoolInt& other) {
+		*this = other;
+	}
+	BoolInt(const BoolInt& other, bool newBool01) {
+		this->bool01 = newBool01;
+		*this = other;
+		this->bool01 = newBool01;
+	}
+
+	inline void clear()
+	{
+		i.clear();
+		b.clear();
+	}
+
+	inline BoolInt& operator=(const BoolInt& other)
+	{
+		clear();
+		bool01.clear();
+
+		if (other.b.set()) b = other.b;
+		if (other.i.set()) i = other.i;
+
+		if (other.bool01.set())
+			bool01 = other.bool01;
+
+		return *this;
+	}
+
+	inline BoolInt& operator=(BoolInt&& other)
+	{
+		clear();
+		bool01.clear();
+
+		if (other.b.set()) b = other.b;
+		if (other.i.set()) i = other.i;
+
+		if (other.bool01.set())
+			bool01 = other.bool01;
+
+		return *this;
+	}
+
+	inline BoolInt& operator=(int val)
+	{
+		clear();
+		i = val;
+		return *this;
+	}
+
+	inline BoolInt& operator=(bool val)
+	{
+		clear();
+		b = val;
+		return *this;
+	}
+
+	inline BoolInt& operator=(const char* s)
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (!s)
+			throw std::invalid_argument(
+				"BoolInt value from <null> string is is not supported");
+
+		std::string src(s);
+		return (*this = src);
+	}
+
+	inline BoolInt& operator=(std::string src)
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		static const Settable<bool> b0(false);
+		static const Settable<bool> b1(true);
+
+		// NOTE: Not a pointer, is not null at least
+		if (src.empty())
+			throw std::invalid_argument(
+				"BoolInt value from <empty> string is is not supported");
+
+		clear();
+
+		if ("false" == src) { b = b0; return *this; }
+		if ("off"   == src) { b = b0; return *this; }
+		if ("0"     == src) {
+			if (bool01.set() && bool01 == false) {
+				i = 0;
+			} else {
+				b = b0;
+			}
+			return *this;
+		}
+		if ("no"    == src) { b = b0; return *this; }
+
+		if ("true"  == src) { b = b1; return *this; }
+		if ("on"    == src) { b = b1; return *this; }
+		if ("1"     == src) {
+			if (bool01.set() && bool01 == false) {
+				i = 1;
+			} else {
+				b = b1;
+			}
+			return *this;
+		}
+		if ("yes"   == src) { b = b1; return *this; }
+		if ("ok"    == src) { b = b1; return *this; }
+
+		std::stringstream ss(src);
+		int result;
+		if (ss >> result && ss.rdbuf()->in_avail() == 0) {
+			// Conversion succeeded and all chars were read
+			// (e.g. not a decimal number)
+			i = result;
+#ifdef DEBUG
+			std::cerr << "BoolInt assigned from '" << src
+				<< "': got int '" << result << "'"
+				<< " stream empty? " << ss.rdbuf()->in_avail()
+				<< std::endl;
+#endif
+			return *this;
+		}
+
+		throw std::invalid_argument("BoolInt value from '" + src +
+			"' string not understood as bool nor int");
+	}
+
+	inline BoolInt& operator<<(bool other)
+	{
+		*this = other;
+		return *this;
+	}
+
+	inline BoolInt& operator<<(int other)
+	{
+		*this = other;
+		return *this;
+	}
+
+	inline BoolInt& operator<<(std::string other)
+	{
+		*this = other;
+		return *this;
+	}
+
+	inline BoolInt& operator<<(const char* other)
+	{
+		*this = other;
+		return *this;
+	}
+
+	inline bool operator==(const BoolInt& other)const
+	{
+		// Either direct values are set and then equal; optionally
+		// else numeric values of int and bool are cross-equal.
+		if (b.set() && other.b.set()) return (b == other.b);
+		if (i.set() && other.i.set()) return (i == other.i);
+
+		if ((bool01.set() && bool01 == true)
+		|| (!bool01.set() && other.bool01.set() && other.bool01 == true)
+		) {
+			// false if at least one object has neither i nor b
+			// values "set()", or if their numeric values do not
+			// match up as 0 or 1 exactly vs. boolean values.
+			if (i.set() && other.b.set())
+				return ( (other.b && i == 1) || (!other.b && i == 0) );
+			if (b.set() && other.i.set())
+				return ( (b && other.i == 1) || (!b && other.i == 0) );
+		}
+
+		return false;
+	}
+
+	inline bool operator==(const bool other)const
+	{
+		if (b.set()) return (b == other);
+		if (bool01.set() && bool01 == true) {
+			if (i.set())
+				return ((other && i == 1) || (!other && i == 0));
+		}
+		return false;
+	}
+
+	inline bool operator==(const int other)const
+	{
+		if (i.set()) return (i == other);
+		if (bool01.set() && bool01 == true) {
+			if (b.set())
+				return ((b && other == 1) || (!b && other == 0));
+		}
+		return false;
+	}
+
+	inline bool operator==(const std::string other)const
+	{
+		BoolInt tmp;
+		if (bool01.set())
+			tmp.bool01 = bool01;
+		tmp = other;
+		return (*this == tmp);
+	}
+
+	inline bool operator==(const char* s)const
+	{
+		if (!s)
+			return false;
+
+		std::string src(s);
+		return (*this == src);
+	}
+
+	inline bool set()const
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (i.set() && b.set())
+			throw std::invalid_argument(
+				"BoolInt value somehow got both bool and int values set");
+
+		return (i.set() || b.set());
+	}
+
+	operator int()
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (i.set()) return i;
+		if (bool01.set() && bool01 == true) {
+			if (b.set()) {
+				/** Cause use of operator to avoid warnings like
+				 * "may be used uninitialized in this function"
+				 */
+				if (b == true) return 1;
+				return 0;
+			}
+		} else {
+			throw std::invalid_argument(
+				"BoolInt value not set to int");
+		}
+
+		throw std::invalid_argument(
+			"BoolInt value not set, neither to bool nor to int");
+	}
+
+	operator bool()
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (b.set()) return b;
+		if (bool01.set() && bool01 == true) {
+			if (i.set()) {
+				if (i == 0) return false;
+				if (i == 1) return true;
+			}
+		} else {
+			throw std::invalid_argument(
+				"BoolInt value not set to bool");
+		}
+
+		throw std::invalid_argument(
+			"BoolInt value not set, neither to bool nor to int");
+	}
+
+	inline std::string toString()const
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		if (b.set()) {
+			if (b == true) return "yes";
+			return "no";
+		}
+
+		if (i.set()) {
+			if (bool01.set() && bool01 == true) {
+				if (i == 0) return "no";
+				if (i == 1) return "yes";
+			}
+
+			std::ostringstream ss;
+			ss << i;
+			return ss.str();
+		}
+
+		throw std::invalid_argument(
+			"BoolInt value not set, neither to bool nor to int");
+	}
+
+	// FIXME: `std::string s = bi;` just won't work
+	// but we can use `s = bi.toString()` or `cout << bi`
+	operator std::string()const {
+		return this->toString();
+	}
+
+	operator std::string&()const {
+		return *(new std::string(this->operator std::string()));
+	}
+};
+
+std::ostream& operator << (std::ostream &os, const BoolInt &bi);
+inline std::ostream& operator << (std::ostream &os, const BoolInt &bi) {
+	return (os << bi.toString());
+}
+
+
+/**
+ * \brief	Certificate Identification structure for NUT
+ *
+ * Contains a certificate name and database password
+ */
+struct CertIdent
+{
+	Settable<std::string> certName, certDbPass;
+
+	inline bool operator==(const CertIdent& ident)const
+	{
+		return certName == ident.certName && certDbPass == ident.certDbPass;
+	}
+
+	inline bool set()const
+	{
+		return certName.set() && certDbPass.set();
+	}
+};
+
+
+/**
+ * \brief	Certificate protected host structure for NUT
+ *
+ * Contains a host name, certificate name and option flags
+ */
+struct CertHost
+{
+	Settable<std::string> host, certName;
+	nut::BoolInt certVerify, forceSsl;
+
+	inline bool operator==(const CertHost& other)const
+	{
+		return certName == other.certName
+			&& host == other.host
+			&& certVerify == other.certVerify
+			&& forceSsl == other.forceSsl;
+	}
+
+	inline bool set()const
+	{
+		return certName.set() && host.set()
+			&& certVerify.set() && forceSsl.set();
+	}
+};
+
+
 /**
  * NUT config parser.
  */
@@ -519,6 +972,175 @@ class GenericConfiguration : public BaseConfiguration, public Serialisable
 		setStr("", entry, value);
 	}
 
+	/**
+	 *  \brief  Configuration flag getter
+	 *
+	 *  False is returned if the section or entry doesn't exist.
+	 *  If a flag exists in configuration (any value is ignored),
+	 *  it is effectively True.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *
+	 *  \return Configuration parameter as boolean
+	 */
+	bool getFlag(
+		const std::string & section,
+		const std::string & entry) const;
+
+	/**
+	 *  \brief  Global scope configuration flag getter
+	 *
+	 *  False is returned if the entry doesn't exist.
+	 *  If a flag exists in configuration (any value is ignored),
+	 *  it is effectively True.
+	 *
+	 *  \param  entry  Entry name
+	 *
+	 *  \return Configuration parameter as boolean
+	 */
+	inline bool getFlag(const std::string & entry) const
+	{
+		return getFlag("", entry);
+	}
+
+	/**
+	 *  \brief  Configuration flag setter (mentioned == true)
+	 *
+	 *  Note: to unset a flag, we just use remove() method.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 */
+	void setFlag(
+		const std::string & section,
+		const std::string & entry,
+		bool                val = true);
+
+	/**
+	 *  \brief  Global scope configuration flag setter (mentioned == true)
+	 *
+	 *  Note: to unset a flag, we just use remove() method.
+	 *
+	 *  \param  entry    Entry name
+	 */
+	inline void setFlag(
+		const std::string & entry,
+		bool                val = true)
+	{
+		setFlag("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration boolean option getter
+	 *
+	 *  Value depends on original string representation of a setting.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as boolean (or the default if not defined)
+	 */
+	bool getBool(
+		const std::string & section,
+		const std::string & entry,
+		bool                val = false) const;
+
+	/**
+	 *  \brief  Configuration boolean option getter
+	 *
+	 *  Value depends on original string representation of a setting.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as boolean (or the default if not defined)
+	 */
+	// Avoid error: implicit conversion turns string literal
+	//       into bool: 'const char[7]' to 'bool'
+	bool getBool(
+		const std::string & section,
+		const char        * entry,
+		bool                val = false) const
+	{
+		return getBool(section, std::string(entry), val);
+	}
+
+	/**
+	 *  \brief  Global scope configuration boolean option getter
+	 *
+	 *  Value depends on original string representation of a setting.
+	 *
+	 *  \param  entry  Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as boolean (or the default if not defined)
+	 */
+	inline bool getBool(const std::string & entry, bool val = false) const
+	{
+		return getBool("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration boolean option setter
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBool(
+		const std::string & section,
+		const std::string & entry,
+		bool                val = true)
+	{
+		setStr(section, entry, bool2str(val));
+	}
+
+	/**
+	 *  \brief  Global scope configuration boolean option setter
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBool(
+		const std::string & entry,
+		bool                val = true)
+	{
+		setBool("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration boolean option setter from a string
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBool(
+		const std::string & section,
+		const std::string & entry,
+		const std::string & val = "true")
+	{
+		// Normalize:
+		bool b = str2bool(val);
+		setStr(section, entry, bool2str(b));
+	}
+
+	/**
+	 *  \brief  Global scope configuration boolean option setter from a string
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBool(
+		const std::string & entry,
+		const std::string & val = "true")
+	{
+		setBool("", entry, val);
+	}
+
 	/**
 	 *  \brief  Configuration number getter
 	 *
@@ -571,6 +1193,110 @@ class GenericConfiguration : public BaseConfiguration, public Serialisable
 		setInt("", entry, val);
 	}
 
+	/**
+	 *  \brief  Configuration number getter (hex value even if without leading "0x")
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as number (or the default if not defined)
+	 */
+	long long int getIntHex(
+		const std::string & section,
+		const std::string & entry,
+		long long int       val = 0) const;
+
+	/**
+	 *  \brief  Global scope configuration number getter (hex value even if without leading "0x")
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as number (or the default if not defined)
+	 */
+	inline long long int getIntHex(const std::string & entry, long long int val = 0) const
+	{
+		return getIntHex("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration number setter (hex value even if without leading "0x")
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	void setIntHex(
+		const std::string & section,
+		const std::string & entry,
+		long long int       val);
+
+	/**
+	 *  \brief  Global scope configuration number setter (hex value even if without leading "0x")
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setIntHex(
+		const std::string & entry,
+		long long int       val)
+	{
+		setIntHex("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration floating-point number getter
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as number (or the default if not defined)
+	 */
+	double getDouble(
+		const std::string & section,
+		const std::string & entry,
+		double              val = 0.0) const;
+
+	/**
+	 *  \brief  Global scope configuration floating-point number getter
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as number (or the default if not defined)
+	 */
+	inline double getDouble(const std::string & entry, double val = 0.0) const
+	{
+		return getDouble("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration floating-point number setter
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	void setDouble(
+		const std::string & section,
+		const std::string & entry,
+		double              val);
+
+	/**
+	 *  \brief  Global scope configuration floating-point number setter
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setDouble(
+		const std::string & entry,
+		double              val)
+	{
+		setDouble("", entry, val);
+	}
+
 	/**
 	 *  \brief  Cast numeric type with range check
 	 *
@@ -607,13 +1333,84 @@ class GenericConfiguration : public BaseConfiguration, public Serialisable
 		return static_cast<T>(number);
 	}
 
+	/**
+	 *  \brief  Configuration mixed boolean/int option getter
+	 *
+	 *  Value depends on original string representation of a setting.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as BoolInt type for original
+	 *          values which have a boolean or integer-numeric meaning
+	 *          (or the default if not defined)
+	 */
+	nut::BoolInt getBoolInt(
+		const std::string & section,
+		const std::string & entry,
+		nut::BoolInt        val = false) const;
+
+	/**
+	 *  \brief  Global scope configuration mixed boolean/int option getter
+	 *
+	 *  Value depends on original string representation of a setting.
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 *
+	 *  \return Configuration parameter as BoolInt type for original
+	 *          values which have a boolean or integer-numeric meaning
+	 *          (or the default if not defined)
+	 */
+	inline nut::BoolInt getBoolInt(const std::string & entry, nut::BoolInt val = false) const
+	{
+		return getBoolInt("", entry, val);
+	}
+
+	/**
+	 *  \brief  Configuration mixed boolean/int option setter
+	 *
+	 *  Input value types are auto-converted through BoolInt
+	 *  type for sanity checks (e.g. throw exceptions for
+	 *  invalid string contents) and are stored as strings
+	 *  internally.
+	 *
+	 *  \param  section  Section name
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBoolInt(
+		const std::string & section,
+		const std::string & entry,
+		nut::BoolInt        val = true)
+#if (defined __cplusplus) && (__cplusplus < 201100)
+		throw(std::invalid_argument)
+#endif
+	{
+		setStr(section, entry, val);
+	}
+
+	/**
+	 *  \brief  Global scope configuration mixed boolean/int option setter
+	 *
+	 *  \param  entry    Entry name
+	 *  \param  val      Default value
+	 */
+	inline void setBoolInt(
+		const std::string & entry,
+		nut::BoolInt        val = true)
+	{
+		setBoolInt("", entry, val);
+	}
+
 	/**
 	 *  \brief  Resolve string as Boolean value
 	 *
 	 *  \param  str  String
 	 *
 	 *  \retval true  IFF the string expresses a known true value
-	 *  \retval false otherwise
+	 *  \retval false otherwise (no errors emitted for bogus inputs)
 	 */
 	static bool str2bool(const std::string & str);
 
@@ -636,8 +1433,17 @@ class UpsmonConfiguration : public Serialisable
 	UpsmonConfiguration();
 	void parseFromString(const std::string& str);
 
+	Settable<int>          debugMin, pollFailLogThrottleMax;
+	Settable<int>          offDuration, oblbDuration;
 	Settable<std::string>  runAsUser, shutdownCmd, notifyCmd, powerDownFlag;
-	Settable<unsigned int> minSupplies, poolFreq, poolFreqAlert, hotSync;
+	/* yes|no (boolean) or a delay */
+	Settable<nut::BoolInt> shutdownExit;
+	/* practically boolean, but in 0|1 written form (bool01 fiddling) */
+	Settable<nut::BoolInt> certVerify, forceSsl;
+	Settable<std::string>  certPath;
+	CertIdent              certIdent;
+	std::list<CertHost>    certHosts;
+	Settable<unsigned int> minSupplies, pollFreq, pollFreqAlert, hostSync;
 	Settable<unsigned int> deadTime, rbWarnTime, noCommWarnTime, finalDelay;
 
 	enum NotifyFlag {
@@ -648,7 +1454,7 @@ class UpsmonConfiguration : public Serialisable
 	};
 
 	enum NotifyType {
-		NOTIFY_ONLINE,
+		NOTIFY_ONLINE = 0,
 		NOTIFY_ONBATT,
 		NOTIFY_LOWBATT,
 		NOTIFY_FSD,
@@ -658,6 +1464,16 @@ class UpsmonConfiguration : public Serialisable
 		NOTIFY_REPLBATT,
 		NOTIFY_NOCOMM,
 		NOTIFY_NOPARENT,
+		NOTIFY_CAL,
+		NOTIFY_NOTCAL,
+		NOTIFY_OFF,
+		NOTIFY_NOTOFF,
+		NOTIFY_BYPASS,
+		NOTIFY_NOTBYPASS,
+
+		NOTIFY_SUSPEND_STARTING = 30,
+		NOTIFY_SUSPEND_FINISHED,
+
 		NOTIFY_TYPE_MAX
 	};
 
@@ -672,7 +1488,7 @@ class UpsmonConfiguration : public Serialisable
 		uint16_t port;
 		unsigned int powerValue;
 		std::string username, password;
-		bool isMaster;
+		bool isPrimary;
 	};
 
 	std::list<Monitor> monitors;
@@ -722,6 +1538,11 @@ class NutConfiguration: public Serialisable
 
 	Settable<NutMode> mode;
 
+	Settable<bool>		allowNoDevice, allowNotAllListeners, poweroffQuiet;
+	Settable<std::string>	upsdOptions, upsmonOptions;
+	Settable<unsigned int>	poweroffWait;
+	Settable<int>		debugLevel;
+
 	static NutMode NutModeFromString(const std::string& str);
 
 	/** Serialisable interface implementation \{ */
@@ -755,8 +1576,10 @@ class UpsdConfiguration : public Serialisable
 	UpsdConfiguration();
 	void parseFromString(const std::string& str);
 
-	Settable<unsigned int> maxAge, maxConn;
-	Settable<std::string>  statePath, certFile;
+	Settable<int> debugMin;
+	Settable<unsigned int> maxAge, maxConn, trackingDelay, certRequestLevel;
+	Settable<std::string>  statePath, certFile, certPath;
+	Settable<bool> allowNoDevice, allowNotAllListeners, disableWeakSsl;
 
 	struct Listen
 	{
@@ -770,6 +1593,8 @@ class UpsdConfiguration : public Serialisable
 	};
 	std::list<Listen> listens;
 
+	CertIdent certIdent;
+
 	/** Serialisable interface implementation \{ */
 	bool parseFrom(NutStream & istream) override;
 	bool writeTo(NutStream & ostream) const override;
@@ -800,22 +1625,66 @@ class UpsdConfigParser : public NutConfigParser
 /** UPS configuration */
 class UpsConfiguration : public GenericConfiguration
 {
+	/* Note: key words for ups.conf are well collected from sources
+	 * by augeas lens preparation scripts. Maintainers of this class
+	 * can consume that information like this to see key words in
+	 * context of their use in sources and documentation (omit the
+	 * `continue` in grep of `nutconf.hpp` to see details of ALL
+	 * keywords and not just those not yet covered by this class
+	 * (e.g. to verify handling as str/int/bool/flag... types):
+
+:; ( cd scripts/augeas && python ./gen-nutupsconf-aug.py.in )
+
+:; grep -E '[=|] "' scripts/augeas/nutupsconf.aug.in | awk '{print $NF}' | tr -d '"' \
+  | while read O ; do echo "=== $O :" ; \
+    grep -w '"'"$O"'"' ./include/nutconf.hpp && continue ; \
+    { cd ./docs/man/ && grep -A10 -w "$O" *.txt || echo '!!! UNDOCUMENTED !!!' ; } ; \
+    echo "-----"; { cd ./drivers && grep -A10 -w '"'"$O"'"' *.{c,h} || echo '!!! NOT USED IN CODE !!!' ; } ; \
+    echo "-----"; echo "" ; done | less
+
+	 * Arrange found new keywords into two columns (first would be
+	 * "C names" camel-cased and expanded as deemed fit) and generate
+	 * lines for code blocks below as e.g.:
+:; while read C O ; do \
+   printf '\tinline std::string get%-45sconst { return getStr(ups, "%s"); }\n' \
+      "$C"'(const std::string & ups)' "$O"; \
+   printf '\tinline void set%-75s{ setStr(ups, "%-22s val); }\n' \
+      "$C"'(const std::string & ups, const std::string & val)' "$O"'",' ; \
+   done  < nutupsconf-newnames.bool | sort
+
+	 */
+
 public:
 	/** Global configuration attributes getters and setters \{ */
 
 	inline std::string getChroot()     const { return getStr("chroot"); }
 	inline std::string getDriverPath() const { return getStr("driverpath"); }
+	inline std::string getGroup()      const { return getStr("group"); }
+	inline std::string getSynchronous() const { return getStr("synchronous"); }
 	inline std::string getUser()       const { return getStr("user"); }
 
+	// Flag - if exists then "true"
+	inline bool getNoWait()            const { return getFlag("nowait"); }
+
+	inline long long int getDebugMin()      const { return getInt("debug_min"); }
+	inline long long int getMaxRetry()      const { return getInt("maxretry"); }
 	inline long long int getMaxStartDelay() const { return getInt("maxstartdelay"); }
-	inline long long int getPollInterval() const  { return getInt("pollinterval", 5); }  // TODO: check the default
+	inline long long int getPollInterval()  const { return getInt("pollinterval", 5); }  // TODO: check the default
+	inline long long int getRetryDelay()    const { return getInt("retrydelay"); }
 
 	inline void setChroot(const std::string & path)     { setStr("chroot",     path); }
 	inline void setDriverPath(const std::string & path) { setStr("driverpath", path); }
+	inline void setGroup(const std::string & group)     { setStr("group",      group); }
+	inline void setSynchronous(const std::string & val) { setStr("synchronous", val); }
 	inline void setUser(const std::string & user)       { setStr("user",       user); }
 
+	inline void setNoWait(bool val = true)              { setFlag("nowait",    val); }
+
+	inline void setDebugMin(long long int num)          { setInt("debug_min",     num); }
+	inline void setMaxRetry(long long int num)          { setInt("maxretry",      num); }
 	inline void setMaxStartDelay(long long int delay)   { setInt("maxstartdelay", delay); }
 	inline void setPollInterval(long long int interval) { setInt("pollinterval",  interval); }
+	inline void setRetryDelay(long long int delay)      { setInt("retrydelay",    delay); }
 
 	/** \} */
 
@@ -827,16 +1696,45 @@ class UpsConfiguration : public GenericConfiguration
 		setStr(ups, key, val);
 	}
 
+	/** PUZZLE: What to do about "default.*" and "override.*"
+	 * settings that apply to anything (vars!) that follows?
+	 * Maybe nest the UpsConfiguration objects, and so query
+	 * e.g. upscfg.default.getBatteryNominalVoltage() ?
+	 * Or just keep that info in ConfigParamList per section
+	 * and wrap free-style queries? */
+	inline std::string   getDefaultStr(const std::string & ups, const std::string & key)            const { return getStr(ups, "default." + key); }
+	inline long long int getDefaultInt(const std::string & ups, const std::string & key)            const { return getInt(ups, "default." + key); }
+	inline long long int getDefaultIntHex(const std::string & ups, const std::string & key)         const { return getIntHex(ups, "default." + key); }
+	inline bool          getDefaultFlag(const std::string & ups, const std::string & key)           const { return getFlag(ups, "default." + key); }
+	inline bool          getDefaultBool(const std::string & ups, const std::string & key)           const { return getBool(ups, "default." + key); }
+	inline nut::BoolInt  getDefaultBoolInt(const std::string & ups, const std::string & key)        const { return getBoolInt(ups, "default." + key); }
+	inline double        getDefaultDouble(const std::string & ups, const std::string & key)         const { return getDouble(ups, "default." + key); }
+
+	inline std::string   getOverrideStr(const std::string & ups, const std::string & key)           const { return getStr(ups, "override." + key); }
+	inline long long int getOverrideInt(const std::string & ups, const std::string & key)           const { return getInt(ups, "override." + key); }
+	inline long long int getOverrideIntHex(const std::string & ups, const std::string & key)        const { return getIntHex(ups, "override." + key); }
+	inline bool          getOverrideFlag(const std::string & ups, const std::string & key)          const { return getFlag(ups, "override." + key); }
+	inline bool          getOverrideBool(const std::string & ups, const std::string & key)          const { return getBool(ups, "override." + key); }
+	inline nut::BoolInt  getOverrideBoolInt(const std::string & ups, const std::string & key)       const { return getBoolInt(ups, "override." + key); }
+	inline double        getOverrideDouble(const std::string & ups, const std::string & key)        const { return getDouble(ups, "override." + key); }
+
+	inline void setDefaultStr(const std::string & ups, const std::string & key, const std::string & val)  { setStr(ups, "default." + key, val); }
+	inline void setDefaultInt(const std::string & ups, const std::string & key, long long int val)        { setInt(ups, "default." + key, val); }
+	inline void setDefaultIntHex(const std::string & ups, const std::string & key, long long int val)     { setIntHex(ups, "default." + key, val); }
+	inline void setDefaultFlag(const std::string & ups, const std::string & key, bool val = true)         { setFlag(ups, "default." + key, val); }
+	inline void setDefaultBool(const std::string & ups, const std::string & key, bool val)                { setBool(ups, "default." + key, val); }
+	inline void setDefaultBoolInt(const std::string & ups, const std::string & key, nut::BoolInt val)     { setBoolInt(ups, "default." + key, val); }
+	inline void setDefaultDouble(const std::string & ups, const std::string & key, double val)            { setDouble(ups, "default." + key, val); }
+
+	inline void setOverrideStr(const std::string & ups, const std::string & key, const std::string & val) { setStr(ups, "override." + key, val); }
+	inline void setOverrideInt(const std::string & ups, const std::string & key, long long int val)       { setInt(ups, "override." + key, val); }
+	inline void setOverrideIntHex(const std::string & ups, const std::string & key, long long int val)    { setIntHex(ups, "override." + key, val); }
+	inline void setOverrideFlag(const std::string & ups, const std::string & key, bool val = true)        { setFlag(ups, "override." + key, val); }
+	inline void setOverrideBool(const std::string & ups, const std::string & key, bool val)               { setBool(ups, "override." + key, val); }
+	inline void setOverrideBoolInt(const std::string & ups, const std::string & key, nut::BoolInt val)    { setBoolInt(ups, "override." + key, val); }
+	inline void setOverrideDouble(const std::string & ups, const std::string & key, double val)           { setDouble(ups, "override." + key, val); }
+
 	/** UPS-specific configuration attributes getters and setters \{ */
-	inline std::string getDriver(const std::string & ups)              const { return getStr(ups, "driver"); }
-	inline std::string getDescription(const std::string & ups)         const { return getStr(ups, "desc"); }
-	inline std::string getCP(const std::string & ups)                  const { return getStr(ups, "CP"); }
-	inline std::string getCS(const std::string & ups)                  const { return getStr(ups, "CS"); }
-	inline std::string getID(const std::string & ups)                  const { return getStr(ups, "ID"); }
-	inline std::string getLB(const std::string & ups)                  const { return getStr(ups, "LB"); }
-	inline std::string getLowBatt(const std::string & ups)             const { return getStr(ups, "LowBatt"); }
-	inline std::string getOL(const std::string & ups)                  const { return getStr(ups, "OL"); }
-	inline std::string getSD(const std::string & ups)                  const { return getStr(ups, "SD"); }
 	inline std::string getAuthPassword(const std::string & ups)        const { return getStr(ups, "authPassword"); }
 	inline std::string getAuthProtocol(const std::string & ups)        const { return getStr(ups, "authProtocol"); }
 	inline std::string getAuthType(const std::string & ups)            const { return getStr(ups, "authtype"); }
@@ -844,17 +1742,33 @@ class UpsConfiguration : public GenericConfiguration
 	inline std::string getBatText(const std::string & ups)             const { return getStr(ups, "battext"); }
 	inline std::string getBus(const std::string & ups)                 const { return getStr(ups, "bus"); }
 	inline std::string getCommunity(const std::string & ups)           const { return getStr(ups, "community"); }
+	inline std::string getDriver(const std::string & ups)              const { return getStr(ups, "driver"); }
+	inline std::string getDescription(const std::string & ups)         const { return getStr(ups, "desc"); }
 	inline std::string getFRUID(const std::string & ups)               const { return getStr(ups, "fruid"); }
+	inline std::string getGenericGPIO_Rules(const std::string & ups)   const { return getStr(ups, "rules"); }
+	inline std::string getGenericUPS_BYPASS(const std::string & ups)   const { return getStr(ups, "BYPASS"); }
+	inline std::string getGenericUPS_CP(const std::string & ups)       const { return getStr(ups, "CP"); }
+	inline std::string getGenericUPS_LB(const std::string & ups)       const { return getStr(ups, "LB"); }
+	inline std::string getGenericUPS_OL(const std::string & ups)       const { return getStr(ups, "OL"); }
+	inline std::string getGenericUPS_RB(const std::string & ups)       const { return getStr(ups, "RB"); }
+	inline std::string getGenericUPS_SD(const std::string & ups)       const { return getStr(ups, "SD"); }
+	inline std::string getGroup(const std::string & ups)               const { return getStr(ups, "group"); }
+	inline std::string getID(const std::string & ups)                  const { return getStr(ups, "ID"); }
 	inline std::string getLoadStatus(const std::string & ups)          const { return getStr(ups, "load.status"); }
 	inline std::string getLogin(const std::string & ups)               const { return getStr(ups, "login"); }
+	inline std::string getLowBatt(const std::string & ups)             const { return getStr(ups, "LowBatt"); }
 	inline std::string getLowbatt(const std::string & ups)             const { return getStr(ups, "lowbatt"); }
 	inline std::string getManufacturer(const std::string & ups)        const { return getStr(ups, "manufacturer"); }
 	inline std::string getMethodOfFlowControl(const std::string & ups) const { return getStr(ups, "methodOfFlowControl"); }
 	inline std::string getMIBs(const std::string & ups)                const { return getStr(ups, "mibs"); }
+	inline std::string getModbus_DeviceMfr(const std::string & ups)    const { return getStr(ups, "device_mfr"); }
+	inline std::string getModbus_DeviceModel(const std::string & ups)  const { return getStr(ups, "device_model"); }
+	inline std::string getModbus_Parity(const std::string & ups)       const { return getStr(ups, "parity"); }
+	inline std::string getModbus_PortType(const std::string & ups)     const { return getStr(ups, "porttype"); }
+	inline std::string getModbus_SerParity(const std::string & ups)    const { return getStr(ups, "ser_parity"); }
 	inline std::string getModel(const std::string & ups)               const { return getStr(ups, "model"); }
 	inline std::string getModelName(const std::string & ups)           const { return getStr(ups, "modelname"); }
 	inline std::string getNotification(const std::string & ups)        const { return getStr(ups, "notification"); }
-	inline std::string getOldMAC(const std::string & ups)              const { return getStr(ups, "oldmac"); }
 	inline std::string getPassword(const std::string & ups)            const { return getStr(ups, "password"); }
 	inline std::string getPort(const std::string & ups)                const { return getStr(ups, "port"); }
 	inline std::string getPrefix(const std::string & ups)              const { return getStr(ups, "prefix"); }
@@ -873,87 +1787,200 @@ class UpsConfiguration : public GenericConfiguration
 	inline std::string getShutdownArguments(const std::string & ups)   const { return getStr(ups, "shutdownArguments"); }
 	inline std::string getSNMPversion(const std::string & ups)         const { return getStr(ups, "snmp_version"); }
 	inline std::string getSubdriver(const std::string & ups)           const { return getStr(ups, "subdriver"); }
+	inline std::string getSynchronous(const std::string & ups)         const { return getStr(ups, "synchronous"); }
+	inline std::string getTtyMode(const std::string & ups)             const { return getStr(ups, "ttymode"); }
 	inline std::string getType(const std::string & ups)                const { return getStr(ups, "type"); }
 	inline std::string getUPStype(const std::string & ups)             const { return getStr(ups, "upstype"); }
+	inline std::string getUpsId(const std::string & ups)               const { return getStr(ups, "upsid"); }
+	inline std::string getUsbBusPort(const std::string & ups)          const { return getStr(ups, "busport"); }
+	inline std::string getUsbDevice(const std::string & ups)           const { return getStr(ups, "device"); }
 	inline std::string getUSD(const std::string & ups)                 const { return getStr(ups, "usd"); }
+	inline std::string getUser(const std::string & ups)                const { return getStr(ups, "user"); }
 	inline std::string getUsername(const std::string & ups)            const { return getStr(ups, "username"); }
 	inline std::string getValidationSequence(const std::string & ups)  const { return getStr(ups, "validationSequence"); }
 	inline std::string getVendor(const std::string & ups)              const { return getStr(ups, "vendor"); }
 	inline std::string getVendorID(const std::string & ups)            const { return getStr(ups, "vendorid"); }
+	inline std::string getWorkRangeType(const std::string & ups)       const { return getStr(ups, "work_range_type"); }
 	inline std::string getWUGrace(const std::string & ups)             const { return getStr(ups, "wugrace"); }
 
+	// Items below are "unused" - mostly set in
+	// drivers/nutdrv_qx_masterguard.c
+	inline std::string getFault1(const std::string & ups)              const { return getStr(ups, "fault_1"); }
+	inline std::string getFault2(const std::string & ups)              const { return getStr(ups, "fault_2"); }
+	inline std::string getFault3(const std::string & ups)              const { return getStr(ups, "fault_3"); }
+	inline std::string getFault4(const std::string & ups)              const { return getStr(ups, "fault_4"); }
+	inline std::string getFault5(const std::string & ups)              const { return getStr(ups, "fault_5"); }
+	inline std::string getInputFaultVoltage(const std::string & ups)   const { return getStr(ups, "input_fault_voltage"); }
+	inline std::string getNominalCellVoltage(const std::string & ups)  const { return getStr(ups, "nominal_cell_voltage"); }
+	inline std::string getNumberOfBatteryCells(const std::string & ups)const { return getStr(ups, "number_of_battery_cells"); }
+	inline std::string getOutputVoltages(const std::string & ups)      const { return getStr(ups, "output_voltages"); }
+	inline std::string getRechargeTime(const std::string & ups)        const { return getStr(ups, "recharge_time"); }
+	inline std::string getRuntimeFull(const std::string & ups)         const { return getStr(ups, "runtime_full"); }
+	inline std::string getRuntimeHalf(const std::string & ups)         const { return getStr(ups, "runtime_half"); }
+	inline std::string getSeries(const std::string & ups)              const { return getStr(ups, "series"); }
+
+	// Items below are essentially booleans (expected values
+	// are "enabled/disabled") -- refactoring planned per
+	// https://github.com/networkupstools/nut/issues/2421
+	inline std::string getAdvancedEcoMode(const std::string & ups)     const { return getStr(ups, "advanced_eco_mode"); }
+	inline std::string getAlarmControl(const std::string & ups)        const { return getStr(ups, "alarm_control"); }
+	inline std::string getBatteryAlarm(const std::string & ups)        const { return getStr(ups, "battery_alarm"); }
+	inline std::string getBatteryOpenStatusCheck(const std::string & ups)const { return getStr(ups, "battery_open_status_check"); }
+	inline std::string getBypassAlarm(const std::string & ups)         const { return getStr(ups, "bypass_alarm"); }
+	inline std::string getBypassForbidding(const std::string & ups)    const { return getStr(ups, "bypass_forbidding"); }
+	inline std::string getBypassWhenOff(const std::string & ups)       const { return getStr(ups, "bypass_when_off"); }
+	inline std::string getConstantPhaseAngle(const std::string & ups)  const { return getStr(ups, "constant_phase_angle"); }
+	inline std::string getConverterMode(const std::string & ups)       const { return getStr(ups, "converter_mode"); }
+	inline std::string getEcoMode(const std::string & ups)             const { return getStr(ups, "eco_mode"); }
+	inline std::string getLimitedRuntimeOnBattery(const std::string & ups)const { return getStr(ups, "limited_runtime_on_battery"); }
+	inline std::string getSiteFaultDetection(const std::string & ups)  const { return getStr(ups, "site_fault_detection"); }
+
+	inline long long int getAdvOrder(const std::string & ups)                  const { return getInt(ups, "advorder"); }            // CHECKME
+	inline long long int getAsem_HB(const std::string & ups)                   const { return getInt(ups, "hb"); }
+	inline long long int getAsem_LB(const std::string & ups)                   const { return getInt(ups, "lb"); }
+	inline long long int getBatteryNumber(const std::string & ups)             const { return getInt(ups, "battery_number"); }
+	inline long long int getBatteryPercentage(const std::string & ups)         const { return getInt(ups, "batteryPercentage"); }   // CHECKME
+	inline long long int getBattVoltMult(const std::string & ups)              const { return getInt(ups, "battvoltmult"); }        // CHECKME
+	inline long long int getBaudRate(const std::string & ups)                  const { return getInt(ups, "baud_rate"); }           // CHECKME
+	inline long long int getBaudrate(const std::string & ups)                  const { return getInt(ups, "baudrate"); }            // CHECKME
+	inline long long int getCablePower(const std::string & ups)                const { return getInt(ups, "cablepower"); }          // CHECKME
+	inline long long int getChargeTime(const std::string & ups)                const { return getInt(ups, "chargetime"); }          // CHECKME
+	inline long long int getDaysOff(const std::string & ups)                   const { return getInt(ups, "daysoff"); }             // CHECKME
+	inline long long int getDaySweek(const std::string & ups)                  const { return getInt(ups, "daysweek"); }            // CHECKME
+	inline long long int getDebugMin(const std::string & ups)                  const { return getInt(ups, "debug_min"); }
+	inline long long int getFrequency(const std::string & ups)                 const { return getInt(ups, "frequency"); }           // CHECKME
+	inline long long int getHourOff(const std::string & ups)                   const { return getInt(ups, "houroff"); }             // CHECKME
+	inline long long int getHourOn(const std::string & ups)                    const { return getInt(ups, "houron"); }              // CHECKME
+	inline long long int getI2C_address(const std::string & ups)               const { return getInt(ups, "i2c_address"); }
+	inline long long int getIdleLoad(const std::string & ups)                  const { return getInt(ups, "idleload"); }            // CHECKME
+	inline long long int getInputTimeout(const std::string & ups)              const { return getInt(ups, "input_timeout"); }       // CHECKME
+	inline long long int getInterruptSize(const std::string & ups)             const { return getInt(ups, "interruptsize"); }
+	inline long long int getLineVoltage(const std::string & ups)               const { return getInt(ups, "linevoltage"); }         // CHECKME
+	inline long long int getLoadpercentage(const std::string & ups)            const { return getInt(ups, "loadPercentage"); }      // CHECKME
+	inline long long int getMaxLoad(const std::string & ups)                   const { return getInt(ups, "max_load"); }            // CHECKME
+	inline long long int getMaxPollsWithoutData(const std::string & ups)       const { return getInt(ups, "max_polls_without_data"); }
+	inline long long int getMaxStartDelay(const std::string & ups)             const { return getInt(ups, "maxstartdelay"); }
+	inline long long int getMFR(const std::string & ups)                       const { return getInt(ups, "mfr"); }                 // CHECKME
+	inline long long int getMinCharge(const std::string & ups)                 const { return getInt(ups, "mincharge"); }           // CHECKME
+	inline long long int getMinRuntime(const std::string & ups)                const { return getInt(ups, "minruntime"); }          // CHECKME
+	inline long long int getModbus_ByteTimeoutSec(const std::string & ups)     const { return getInt(ups, "mod_byte_to_s"); }
+	inline long long int getModbus_ByteTimeoutUsec(const std::string & ups)    const { return getInt(ups, "mod_byte_to_us"); }
+	inline long long int getModbus_CHRG_addr(const std::string & ups)          const { return getInt(ups, "CHRG_addr"); }
+	inline long long int getModbus_CHRG_noro(const std::string & ups)          const { return getInt(ups, "CHRG_noro"); }
+	inline long long int getModbus_CHRG_regtype(const std::string & ups)       const { return getInt(ups, "CHRG_regtype"); }
+	inline long long int getModbus_DISCHRG_addr(const std::string & ups)       const { return getInt(ups, "DISCHRG_addr"); }
+	inline long long int getModbus_DISCHRG_noro(const std::string & ups)       const { return getInt(ups, "DISCHRG_noro"); }
+	inline long long int getModbus_DISCHRG_regtype(const std::string & ups)    const { return getInt(ups, "DISCHRG_regtype"); }
+	inline long long int getModbus_DataBits(const std::string & ups)           const { return getInt(ups, "databits"); }
+	inline long long int getModbus_DeviceSlaveId(const std::string & ups)      const { return getInt(ups, "dev_slave_id"); }
+	inline long long int getModbus_FSD_addr(const std::string & ups)           const { return getInt(ups, "FSD_addr"); }
+	inline long long int getModbus_FSD_noro(const std::string & ups)           const { return getInt(ups, "FSD_noro"); }
+	inline long long int getModbus_FSD_pulse_duration(const std::string & ups) const { return getInt(ups, "FSD_pulse_duration"); }
+	inline long long int getModbus_FSD_regtype(const std::string & ups)        const { return getInt(ups, "FSD_regtype"); }
+	inline long long int getModbus_HB_addr(const std::string & ups)            const { return getInt(ups, "HB_addr"); }
+	inline long long int getModbus_HB_noro(const std::string & ups)            const { return getInt(ups, "HB_noro"); }
+	inline long long int getModbus_HB_regtype(const std::string & ups)         const { return getInt(ups, "HB_regtype"); }
+	inline long long int getModbus_LB_addr(const std::string & ups)            const { return getInt(ups, "LB_addr"); }
+	inline long long int getModbus_LB_noro(const std::string & ups)            const { return getInt(ups, "LB_noro"); }
+	inline long long int getModbus_LB_regtype(const std::string & ups)         const { return getInt(ups, "LB_regtype"); }
+	inline long long int getModbus_OB_addr(const std::string & ups)            const { return getInt(ups, "OB_addr"); }
+	inline long long int getModbus_OB_noro(const std::string & ups)            const { return getInt(ups, "OB_noro"); }
+	inline long long int getModbus_OB_regtype(const std::string & ups)         const { return getInt(ups, "OB_regtype"); }
+	inline long long int getModbus_OL_addr(const std::string & ups)            const { return getInt(ups, "OL_addr"); }
+	inline long long int getModbus_OL_noro(const std::string & ups)            const { return getInt(ups, "OL_noro"); }
+	inline long long int getModbus_OL_regtype(const std::string & ups)         const { return getInt(ups, "OL_regtype"); }
+	inline long long int getModbus_RB_addr(const std::string & ups)            const { return getInt(ups, "RB_addr"); }
+	inline long long int getModbus_RB_noro(const std::string & ups)            const { return getInt(ups, "RB_noro"); }
+	inline long long int getModbus_RB_regtype(const std::string & ups)         const { return getInt(ups, "RB_regtype"); }
+	inline long long int getModbus_ResponseTimeoutMsec(const std::string & ups)const { return getInt(ups, "response_timeout_ms"); }
+	inline long long int getModbus_ResponseTimeoutSec(const std::string & ups) const { return getInt(ups, "mod_resp_to_s"); }
+	inline long long int getModbus_ResponseTimeoutUsec(const std::string & ups)const { return getInt(ups, "mod_resp_to_us"); }
+	inline long long int getModbus_RioSlaveId(const std::string & ups)         const { return getInt(ups, "rio_slave_id"); }
+	inline long long int getModbus_SerBaudRate(const std::string & ups)        const { return getInt(ups, "ser_baud_rate"); }
+	inline long long int getModbus_SerDataBit(const std::string & ups)         const { return getInt(ups, "ser_data_bit"); }
+	inline long long int getModbus_SerStopBit(const std::string & ups)         const { return getInt(ups, "ser_stop_bit"); }
+	inline long long int getModbus_SlaveId(const std::string & ups)            const { return getInt(ups, "slaveid"); }
+	inline long long int getModbus_StopBits(const std::string & ups)           const { return getInt(ups, "stopbits"); }
+	inline long long int getNomBattVolt(const std::string & ups)               const { return getInt(ups, "nombattvolt"); }         // CHECKME
+	inline long long int getNumOfBytesFromUPS(const std::string & ups)         const { return getInt(ups, "numOfBytesFromUPS"); }   // CHECKME
+	inline long long int getOffDelay(const std::string & ups)                  const { return getInt(ups, "OffDelay"); }            // CHECKME
+	inline long long int getOffdelay(const std::string & ups)                  const { return getInt(ups, "offdelay"); }            // CHECKME
+	inline long long int getOnDelay(const std::string & ups)                   const { return getInt(ups, "OnDelay"); }             // CHECKME
+	inline long long int getOndelay(const std::string & ups)                   const { return getInt(ups, "ondelay"); }             // CHECKME
+	inline long long int getOnlineDischargeLogThrottleHovercharge(const std::string & ups)const { return getInt(ups, "onlinedischarge_log_throttle_hovercharge"); }
+	inline long long int getOnlineDischargeLogThrottleSec(const std::string & ups)const { return getInt(ups, "onlinedischarge_log_throttle_sec"); }
+	inline long long int getOutputPace(const std::string & ups)                const { return getInt(ups, "output_pace"); }         // CHECKME
+	inline long long int getOutputPhaseAngle(const std::string & ups)          const { return getInt(ups, "output_phase_angle"); }
+	inline long long int getPinsShutdownMode(const std::string & ups)          const { return getInt(ups, "pins_shutdown_mode"); }
+	inline long long int getPollFreq(const std::string & ups)                  const { return getInt(ups, "pollfreq"); }            // CHECKME
+	inline long long int getPowerUp(const std::string & ups)                   const { return getInt(ups, "powerup"); }             // CHECKME
+	inline long long int getPrgShut(const std::string & ups)                   const { return getInt(ups, "prgshut"); }             // CHECKME
+	inline long long int getRebootDelay(const std::string & ups)               const { return getInt(ups, "rebootdelay"); }         // CHECKME
+	inline long long int getSDOrder(const std::string & ups)                   const { return getInt(ups, "sdorder"); }             // TODO: Is that a number?
+	inline long long int getSDtime(const std::string & ups)                    const { return getInt(ups, "sdtime"); }              // CHECKME
+	inline long long int getSemistaticFreq(const std::string & ups)            const { return getInt(ups, "semistaticfreq"); }
+	inline long long int getShutdownDelay(const std::string & ups)             const { return getInt(ups, "shutdown_delay"); }      // CHECKME
+	inline long long int getShutdownDuration(const std::string & ups)          const { return getInt(ups, "shutdown_duration"); }
+	inline long long int getShutdownTimer(const std::string & ups)             const { return getInt(ups, "shutdown_timer"); }
+	inline long long int getSlaveAddress(const std::string & ups)              const { return getInt(ups, "slave_address"); }
+	inline long long int getSnmpRetries(const std::string & ups)               const { return getInt(ups, "snmp_retries"); }
+	inline long long int getSnmpTimeout(const std::string & ups)               const { return getInt(ups, "snmp_timeout"); }
+	inline long long int getStartDelay(const std::string & ups)                const { return getInt(ups, "startdelay"); }          // CHECKME
+	inline long long int getTestTime(const std::string & ups)                  const { return getInt(ups, "testtime"); }            // CHECKME
+	inline long long int getTimeout(const std::string & ups)                   const { return getInt(ups, "timeout"); }             // CHECKME
+	inline long long int getUPSdelayShutdown(const std::string & ups)          const { return getInt(ups, "ups.delay.shutdown"); }  // CHECKME
+	inline long long int getUPSdelayStart(const std::string & ups)             const { return getInt(ups, "ups.delay.start"); }     // CHECKME
+	inline long long int getVoltage(const std::string & ups)                   const { return getInt(ups, "voltage"); }             // CHECKME
+	inline long long int getWaitBeforeReconnect(const std::string & ups)       const { return getInt(ups, "waitbeforereconnect"); }
+
+	/** belkinunv: both a flag (wait for AC power) and value (also wait for charge level) */
+	inline long long int getWait(const std::string & ups)                      const { return getInt(ups, "wait"); }
+
+	/** May be a flag or a number; 0 is among valid values (default -1 for unset) */
+	inline long long int getUsbSetAltInterface(const std::string & ups)        const { return getInt(ups, "usb_set_altinterface", -1); }      // CHECKME
+
+	// NUT specifies these as "hexnum" values (optionally with prefixed 0x but hex anyway)
+	inline long long int getUsbConfigIndex(const std::string & ups)            const { return getIntHex(ups, "usb_config_index"); }           // CHECKME
+	inline long long int getUsbHidDescIndex(const std::string & ups)           const { return getIntHex(ups, "usb_hid_desc_index"); }         // CHECKME
+	inline long long int getUsbHidRepIndex(const std::string & ups)            const { return getIntHex(ups, "usb_hid_rep_index"); }          // CHECKME
+	inline long long int getUsbHidEndpointIn(const std::string & ups)          const { return getIntHex(ups, "usb_hid_ep_in"); }              // CHECKME
+	inline long long int getUsbHidEndpointOut(const std::string & ups)         const { return getIntHex(ups, "usb_hid_ep_out"); }             // CHECKME
+
+	inline double getBatteryMax(const std::string & ups)          const { return getDouble(ups, "battery_max"); }
+	inline double getBatteryMin(const std::string & ups)          const { return getDouble(ups, "battery_min"); }
+	inline double getCSHackDelay(const std::string & ups)         const { return getDouble(ups, "cshdelay"); }
+	inline double getMaxBypassFreq(const std::string & ups)       const { return getDouble(ups, "max_bypass_freq"); }
+	inline double getMaxBypassVolt(const std::string & ups)       const { return getDouble(ups, "max_bypass_volt"); }
+	inline double getMinBypassFreq(const std::string & ups)       const { return getDouble(ups, "min_bypass_freq"); }
+	inline double getMinBypassVolt(const std::string & ups)       const { return getDouble(ups, "min_bypass_volt"); }
+
+	// Flag - if exists then "true"
+	inline bool getCancelShutdown(const std::string & ups) const { return getFlag(ups, "CS"); }
+	inline bool getDumbTerm(const std::string & ups)       const { return getFlag(ups, "dumbterm"); }
+	inline bool getExplore(const std::string & ups)        const { return getFlag(ups, "explore"); }
+	inline bool getFakeLowBatt(const std::string & ups)    const { return getFlag(ups, "fake_lowbatt"); }
+	inline bool getFlash(const std::string & ups)          const { return getFlag(ups, "flash"); }
+	inline bool getIgnoreLB(const std::string & ups)       const { return getFlag(ups, "ignorelb"); }
+	inline bool getNoHang(const std::string & ups)         const { return getFlag(ups, "nohang"); }
+	inline bool getNoRating(const std::string & ups)       const { return getFlag(ups, "norating"); }
+	inline bool getNoTransferOIDs(const std::string & ups) const { return getFlag(ups, "notransferoids"); }
+	inline bool getNoVendor(const std::string & ups)       const { return getFlag(ups, "novendor"); }
+	inline bool getNoWarnNoImp(const std::string & ups)    const { return getFlag(ups, "nowarn_noimp"); }
+	inline bool getOldMAC(const std::string & ups)         const { return getFlag(ups, "oldmac"); }
+	inline bool getPollOnly(const std::string & ups)       const { return getFlag(ups, "pollonly"); }
+	inline bool getSilent(const std::string & ups)         const { return getFlag(ups, "silent"); }
+	inline bool getStatusOnly(const std::string & ups)     const { return getFlag(ups, "status_only"); }
+	inline bool getSubscribe(const std::string & ups)      const { return getFlag(ups, "subscribe"); }
+	inline bool getUseCRLF(const std::string & ups)        const { return getFlag(ups, "use_crlf"); }
+	inline bool getUsePreLF(const std::string & ups)       const { return getFlag(ups, "use_pre_lf"); }
+
+	inline bool getNolock(const std::string & ups)         const { return getBool(ups, "nolock"); }
+	inline bool getCable(const std::string & ups)          const { return getBool(ups, "cable"); }
+	inline bool getFullUpdate(const std::string & ups)     const { return getBool(ups, "full_update"); }
+	inline bool getLangIDfix(const std::string & ups)      const { return getBool(ups, "langid_fix"); }
+	inline bool getLoadOff(const std::string & ups)        const { return getBool(ups, "load.off"); }
+	inline bool getLoadOn(const std::string & ups)         const { return getBool(ups, "load.on"); }
 
-	inline long long int getSDOrder(const std::string & ups)           const { return getInt(ups, "sdorder"); }             // TODO: Is that a number?
-	inline long long int getMaxStartDelay(const std::string & ups)     const { return getInt(ups, "maxstartdelay"); }
-	inline long long int getAdvOrder(const std::string & ups)          const { return getInt(ups, "advorder"); }            // CHECKME
-	inline long long int getBatteryPercentage(const std::string & ups) const { return getInt(ups, "batteryPercentage"); }   // CHECKME
-	inline long long int getOffDelay(const std::string & ups)          const { return getInt(ups, "OffDelay"); }            // CHECKME
-	inline long long int getOnDelay(const std::string & ups)           const { return getInt(ups, "OnDelay"); }             // CHECKME
-	inline long long int getBattVoltMult(const std::string & ups)      const { return getInt(ups, "battvoltmult"); }        // CHECKME
-	inline long long int getBaudRate(const std::string & ups)          const { return getInt(ups, "baud_rate"); }           // CHECKME
-	inline long long int getBaudrate(const std::string & ups)          const { return getInt(ups, "baudrate"); }            // CHECKME
-	inline long long int getCablePower(const std::string & ups)        const { return getInt(ups, "cablepower"); }          // CHECKME
-	inline long long int getChargeTime(const std::string & ups)        const { return getInt(ups, "chargetime"); }          // CHECKME
-	inline long long int getDaysOff(const std::string & ups)           const { return getInt(ups, "daysoff"); }             // CHECKME
-	inline long long int getDaySweek(const std::string & ups)          const { return getInt(ups, "daysweek"); }            // CHECKME
-	inline long long int getFrequency(const std::string & ups)         const { return getInt(ups, "frequency"); }           // CHECKME
-	inline long long int getHourOff(const std::string & ups)           const { return getInt(ups, "houroff"); }             // CHECKME
-	inline long long int getHourOn(const std::string & ups)            const { return getInt(ups, "houron"); }              // CHECKME
-	inline long long int getIdleLoad(const std::string & ups)          const { return getInt(ups, "idleload"); }            // CHECKME
-	inline long long int getInputTimeout(const std::string & ups)      const { return getInt(ups, "input_timeout"); }       // CHECKME
-	inline long long int getLineVoltage(const std::string & ups)       const { return getInt(ups, "linevoltage"); }         // CHECKME
-	inline long long int getLoadpercentage(const std::string & ups)    const { return getInt(ups, "loadPercentage"); }      // CHECKME
-	inline long long int getMaxLoad(const std::string & ups)           const { return getInt(ups, "max_load"); }            // CHECKME
-	inline long long int getMFR(const std::string & ups)               const { return getInt(ups, "mfr"); }                 // CHECKME
-	inline long long int getMinCharge(const std::string & ups)         const { return getInt(ups, "mincharge"); }           // CHECKME
-	inline long long int getMinRuntime(const std::string & ups)        const { return getInt(ups, "minruntime"); }          // CHECKME
-	inline long long int getNomBattVolt(const std::string & ups)       const { return getInt(ups, "nombattvolt"); }         // CHECKME
-	inline long long int getNumOfBytesFromUPS(const std::string & ups) const { return getInt(ups, "numOfBytesFromUPS"); }   // CHECKME
-	inline long long int getOffdelay(const std::string & ups)          const { return getInt(ups, "offdelay"); }            // CHECKME
-	inline long long int getOndelay(const std::string & ups)           const { return getInt(ups, "ondelay"); }             // CHECKME
-	inline long long int getOutputPace(const std::string & ups)        const { return getInt(ups, "output_pace"); }         // CHECKME
-	inline long long int getPollFreq(const std::string & ups)          const { return getInt(ups, "pollfreq"); }            // CHECKME
-	inline long long int getPowerUp(const std::string & ups)           const { return getInt(ups, "powerup"); }             // CHECKME
-	inline long long int getPrgShut(const std::string & ups)           const { return getInt(ups, "prgshut"); }             // CHECKME
-	inline long long int getRebootDelay(const std::string & ups)       const { return getInt(ups, "rebootdelay"); }         // CHECKME
-	inline long long int getSDtime(const std::string & ups)            const { return getInt(ups, "sdtime"); }              // CHECKME
-	inline long long int getShutdownDelay(const std::string & ups)     const { return getInt(ups, "shutdown_delay"); }      // CHECKME
-	inline long long int getStartDelay(const std::string & ups)        const { return getInt(ups, "startdelay"); }          // CHECKME
-	inline long long int getTestTime(const std::string & ups)          const { return getInt(ups, "testtime"); }            // CHECKME
-	inline long long int getTimeout(const std::string & ups)           const { return getInt(ups, "timeout"); }             // CHECKME
-	inline long long int getUPSdelayShutdown(const std::string & ups)  const { return getInt(ups, "ups.delay.shutdown"); }  // CHECKME
-	inline long long int getUPSdelayStart(const std::string & ups)     const { return getInt(ups, "ups.delay.start"); }     // CHECKME
-	inline long long int getVoltage(const std::string & ups)           const { return getInt(ups, "voltage"); }             // CHECKME
-	inline long long int getWait(const std::string & ups)              const { return getInt(ups, "wait"); }                // CHECKME
-
-	inline bool getNolock(const std::string & ups)         const { return str2bool(getStr(ups, "nolock")); }
-	inline bool getCable(const std::string & ups)          const { return str2bool(getStr(ups, "cable")); }
-	inline bool getDumbTerm(const std::string & ups)       const { return str2bool(getStr(ups, "dumbterm")); }
-	inline bool getExplore(const std::string & ups)        const { return str2bool(getStr(ups, "explore")); }
-	inline bool getFakeLowBatt(const std::string & ups)    const { return str2bool(getStr(ups, "fake_lowbatt")); }
-	inline bool getFlash(const std::string & ups)          const { return str2bool(getStr(ups, "flash")); }
-	inline bool getFullUpdate(const std::string & ups)     const { return str2bool(getStr(ups, "full_update")); }
-	inline bool getLangIDfix(const std::string & ups)      const { return str2bool(getStr(ups, "langid_fix")); }
-	inline bool getLoadOff(const std::string & ups)        const { return str2bool(getStr(ups, "load.off")); }
-	inline bool getLoadOn(const std::string & ups)         const { return str2bool(getStr(ups, "load.on")); }
-	inline bool getNoHang(const std::string & ups)         const { return str2bool(getStr(ups, "nohang")); }
-	inline bool getNoRating(const std::string & ups)       const { return str2bool(getStr(ups, "norating")); }
-	inline bool getNoTransferOIDs(const std::string & ups) const { return str2bool(getStr(ups, "notransferoids")); }
-	inline bool getNoVendor(const std::string & ups)       const { return str2bool(getStr(ups, "novendor")); }
-	inline bool getNoWarnNoImp(const std::string & ups)    const { return str2bool(getStr(ups, "nowarn_noimp")); }
-	inline bool getPollOnly(const std::string & ups)       const { return str2bool(getStr(ups, "pollonly")); }
-	inline bool getSilent(const std::string & ups)         const { return str2bool(getStr(ups, "silent")); }
-	inline bool getStatusOnly(const std::string & ups)     const { return str2bool(getStr(ups, "status_only")); }
-	inline bool getSubscribe(const std::string & ups)      const { return str2bool(getStr(ups, "subscribe")); }
-	inline bool getUseCRLF(const std::string & ups)        const { return str2bool(getStr(ups, "use_crlf")); }
-	inline bool getUsePreLF(const std::string & ups)       const { return str2bool(getStr(ups, "use_pre_lf")); }
-
-
-	inline void setDriver(const std::string & ups, const std::string & driver)                { setStr(ups, "driver",              driver); }
-	inline void setDescription(const std::string & ups, const std::string & desc)             { setStr(ups, "desc",                desc); }
-	inline void setLowBatt(const std::string & ups, const std::string & lowbatt)              { setStr(ups, "LowBatt",             lowbatt); }
-	inline void setOL(const std::string & ups, const std::string & ol)                        { setStr(ups, "OL",                  ol); }
-	inline void setSD(const std::string & ups, const std::string & sd)                        { setStr(ups, "SD",                  sd); }
 	inline void setAuthPassword(const std::string & ups, const std::string & auth_passwd)     { setStr(ups, "authPassword",        auth_passwd); }
 	inline void setAuthProtocol(const std::string & ups, const std::string & auth_proto)      { setStr(ups, "authProtocol",        auth_proto); }
 	inline void setAuthType(const std::string & ups, const std::string & authtype)            { setStr(ups, "authtype",            authtype); }
@@ -961,17 +1988,32 @@ class UpsConfiguration : public GenericConfiguration
 	inline void setBatText(const std::string & ups, const std::string & battext)              { setStr(ups, "battext",             battext); }
 	inline void setBus(const std::string & ups, const std::string & bus)                      { setStr(ups, "bus",                 bus); }
 	inline void setCommunity(const std::string & ups, const std::string & community)          { setStr(ups, "community",           community); }
+	inline void setDriver(const std::string & ups, const std::string & driver)                { setStr(ups, "driver",              driver); }
+	inline void setDescription(const std::string & ups, const std::string & desc)             { setStr(ups, "desc",                desc); }
 	inline void setFRUID(const std::string & ups, const std::string & fruid)                  { setStr(ups, "fruid",               fruid); }
+	inline void setGenericGPIO_Rules(const std::string & ups, const std::string & val)        { setStr(ups, "rules",               val); }
+	inline void setGenericUPS_BYPASS(const std::string & ups, const std::string & bypass)     { setStr(ups, "BYPASS",              bypass); }
+	inline void setGenericUPS_CP(const std::string & ups, const std::string & cp)             { setStr(ups, "CP",                  cp); }
+	inline void setGenericUPS_LB(const std::string & ups, const std::string & lb)             { setStr(ups, "LB",                  lb); }
+	inline void setGenericUPS_OL(const std::string & ups, const std::string & ol)             { setStr(ups, "OL",                  ol); }
+	inline void setGenericUPS_RB(const std::string & ups, const std::string & rb)             { setStr(ups, "RB",                  rb); }
+	inline void setGenericUPS_SD(const std::string & ups, const std::string & sd)             { setStr(ups, "SD",                  sd); }
+	inline void setGroup(const std::string & ups, const std::string & group)                  { setStr(ups, "group",               group); }
 	inline void setLoadStatus(const std::string & ups, const std::string & load_status)       { setStr(ups, "load.status",         load_status); }
 	inline void setLogin(const std::string & ups, const std::string & login)                  { setStr(ups, "login",               login); }
+	inline void setLowBatt(const std::string & ups, const std::string & lowbatt)              { setStr(ups, "LowBatt",             lowbatt); }
 	inline void setLowbatt(const std::string & ups, const std::string & lowbatt)              { setStr(ups, "lowbatt",             lowbatt); }
 	inline void setManufacturer(const std::string & ups, const std::string & manufacturer)    { setStr(ups, "manufacturer",        manufacturer); }
 	inline void setMethodOfFlowControl(const std::string & ups, const std::string & method)   { setStr(ups, "methodOfFlowControl", method); }
 	inline void setMIBs(const std::string & ups, const std::string & mibs)                    { setStr(ups, "mibs",                mibs); }
+	inline void setModbus_DeviceMfr(const std::string & ups, const std::string & val)         { setStr(ups, "device_mfr",          val); }
+	inline void setModbus_DeviceModel(const std::string & ups, const std::string & val)       { setStr(ups, "device_model",        val); }
+	inline void setModbus_Parity(const std::string & ups, const std::string & val)            { setStr(ups, "parity",              val); }
+	inline void setModbus_PortType(const std::string & ups, const std::string & val)          { setStr(ups, "porttype",            val); }
+	inline void setModbus_SerParity(const std::string & ups, const std::string & val)         { setStr(ups, "ser_parity",          val); }
 	inline void setModel(const std::string & ups, const std::string & model)                  { setStr(ups, "model",               model); }
 	inline void setModelName(const std::string & ups, const std::string & modelname)          { setStr(ups, "modelname",           modelname); }
 	inline void setNotification(const std::string & ups, const std::string & notification)    { setStr(ups, "notification",        notification); }
-	inline void setOldMAC(const std::string & ups, const std::string & oldmac)                { setStr(ups, "oldmac",              oldmac); }
 	inline void setPassword(const std::string & ups, const std::string & password)            { setStr(ups, "password",            password); }
 	inline void setPort(const std::string & ups, const std::string & port)                    { setStr(ups, "port",                port); }
 	inline void setPrefix(const std::string & ups, const std::string & prefix)                { setStr(ups, "prefix",              prefix); }
@@ -990,79 +2032,199 @@ class UpsConfiguration : public GenericConfiguration
 	inline void setShutdownArguments(const std::string & ups, const std::string & sd_args)    { setStr(ups, "shutdownArguments",   sd_args); }
 	inline void setSNMPversion(const std::string & ups, const std::string & snmp_version)     { setStr(ups, "snmp_version",        snmp_version); }
 	inline void setSubdriver(const std::string & ups, const std::string & subdriver)          { setStr(ups, "subdriver",           subdriver); }
+	inline void setSynchronous(const std::string & ups, const std::string & synchronous)      { setStr(ups, "synchronous",         synchronous); }
+	inline void setTtyMode(const std::string & ups, const std::string & val)                  { setStr(ups, "ttymode",             val); }
 	inline void setType(const std::string & ups, const std::string & type)                    { setStr(ups, "type",                type); }
 	inline void setUPStype(const std::string & ups, const std::string & upstype)              { setStr(ups, "upstype",             upstype); }
+	inline void setUpsId(const std::string & ups, const std::string & val)                    { setStr(ups, "upsid",               val); }
+	inline void setUsbBusPort(const std::string & ups, const std::string & val)               { setStr(ups, "busport",             val); }
+	inline void setUsbDevice(const std::string & ups, const std::string & val)                { setStr(ups, "device",              val); }
 	inline void setUSD(const std::string & ups, const std::string & usd)                      { setStr(ups, "usd",                 usd); }
 	inline void setUsername(const std::string & ups, const std::string & username)            { setStr(ups, "username",            username); }
+	inline void setUser(const std::string & ups, const std::string & user)                    { setStr(ups, "user",                user); }
 	inline void setValidationSequence(const std::string & ups, const std::string & valid_seq) { setStr(ups, "validationSequence",  valid_seq); }
 	inline void setVendor(const std::string & ups, const std::string & vendor)                { setStr(ups, "vendor",              vendor); }
 	inline void setVendorID(const std::string & ups, const std::string & vendorid)            { setStr(ups, "vendorid",            vendorid); }
+	inline void setWorkRangeType(const std::string & ups, const std::string & val)            { setStr(ups, "work_range_type",     val); }
 	inline void setWUGrace(const std::string & ups, const std::string & wugrace)              { setStr(ups, "wugrace",             wugrace); }
 
-	inline void setSDOrder(const std::string & ups, long long int ord)             { setInt(ups, "sdorder",            ord); }
-	inline void setMaxStartDelay(const std::string & ups, long long int delay)     { setInt(ups, "maxstartdelay",      delay); }
-	inline void setADVorder(const std::string & ups, long long int advorder)       { setInt(ups, "advorder",           advorder); }     // CHECKME
-	inline void setBatteryPercentage(const std::string & ups, long long int batt)  { setInt(ups, "batteryPercentage",  batt); }         // CHECKME
-	inline void setOffDelay(const std::string & ups, long long int offdelay)       { setInt(ups, "OffDelay",           offdelay); }     // CHECKME
-	inline void setOnDelay(const std::string & ups, long long int ondelay)         { setInt(ups, "OnDelay",            ondelay); }      // CHECKME
-	inline void setBattVoltMult(const std::string & ups, long long int mult)       { setInt(ups, "battvoltmult",       mult); }         // CHECKME
-	inline void setBaudRate(const std::string & ups, long long int baud_rate)      { setInt(ups, "baud_rate",          baud_rate); }    // CHECKME
-	inline void setBaudrate(const std::string & ups, long long int baudrate)       { setInt(ups, "baudrate",           baudrate); }     // CHECKME
-	inline void setCablePower(const std::string & ups, long long int cablepower)   { setInt(ups, "cablepower",         cablepower); }   // CHECKME
-	inline void setChargeTime(const std::string & ups, long long int chargetime)   { setInt(ups, "chargetime",         chargetime); }   // CHECKME
-	inline void setDaysOff(const std::string & ups, long long int daysoff)         { setInt(ups, "daysoff",            daysoff); }      // CHECKME
-	inline void setDaysWeek(const std::string & ups, long long int daysweek)       { setInt(ups, "daysweek",           daysweek); }     // CHECKME
-	inline void setFrequency(const std::string & ups, long long int frequency)     { setInt(ups, "frequency",          frequency); }    // CHECKME
-	inline void setHourOff(const std::string & ups, long long int houroff)         { setInt(ups, "houroff",            houroff); }      // CHECKME
-	inline void setHourOn(const std::string & ups, long long int houron)           { setInt(ups, "houron",             houron); }       // CHECKME
-	inline void setIdleLoad(const std::string & ups, long long int idleload)       { setInt(ups, "idleload",           idleload); }     // CHECKME
-	inline void setInputTimeout(const std::string & ups, long long int timeout)    { setInt(ups, "input_timeout",      timeout); }      // CHECKME
-	inline void setLineVoltage(const std::string & ups, long long int linevoltage) { setInt(ups, "linevoltage",        linevoltage); }  // CHECKME
-	inline void setLoadpercentage(const std::string & ups, long long int load)     { setInt(ups, "loadPercentage",     load); }         // CHECKME
-	inline void setMaxLoad(const std::string & ups, long long int max_load)        { setInt(ups, "max_load",           max_load); }     // CHECKME
-	inline void setMFR(const std::string & ups, long long int mfr)                 { setInt(ups, "mfr",                mfr); }          // CHECKME
-	inline void setMinCharge(const std::string & ups, long long int mincharge)     { setInt(ups, "mincharge",          mincharge); }    // CHECKME
-	inline void setMinRuntime(const std::string & ups, long long int minruntime)   { setInt(ups, "minruntime",         minruntime); }   // CHECKME
-	inline void setNomBattVolt(const std::string & ups, long long int nombattvolt) { setInt(ups, "nombattvolt",        nombattvolt); }  // CHECKME
-	inline void setNumOfBytesFromUPS(const std::string & ups, long long int bytes) { setInt(ups, "numOfBytesFromUPS",  bytes); }        // CHECKME
-	inline void setOffdelay(const std::string & ups, long long int offdelay)       { setInt(ups, "offdelay",           offdelay); }     // CHECKME
-	inline void setOndelay(const std::string & ups, long long int ondelay)         { setInt(ups, "ondelay",            ondelay); }      // CHECKME
-	inline void setOutputPace(const std::string & ups, long long int output_pace)  { setInt(ups, "output_pace",        output_pace); }  // CHECKME
-	inline void setPollFreq(const std::string & ups, long long int pollfreq)       { setInt(ups, "pollfreq",           pollfreq); }     // CHECKME
-	inline void setPowerUp(const std::string & ups, long long int powerup)         { setInt(ups, "powerup",            powerup); }      // CHECKME
-	inline void setPrgShut(const std::string & ups, long long int prgshut)         { setInt(ups, "prgshut",            prgshut); }      // CHECKME
-	inline void setRebootDelay(const std::string & ups, long long int delay)       { setInt(ups, "rebootdelay",        delay); }        // CHECKME
-	inline void setSDtime(const std::string & ups, long long int sdtime)           { setInt(ups, "sdtime",             sdtime); }       // CHECKME
-	inline void setShutdownDelay(const std::string & ups, long long int delay)     { setInt(ups, "shutdown_delay",     delay); }        // CHECKME
-	inline void setStartDelay(const std::string & ups, long long int delay)        { setInt(ups, "startdelay",         delay); }        // CHECKME
-	inline void setTestTime(const std::string & ups, long long int testtime)       { setInt(ups, "testtime",           testtime); }     // CHECKME
-	inline void setTimeout(const std::string & ups, long long int timeout)         { setInt(ups, "timeout",            timeout); }      // CHECKME
-	inline void setUPSdelayShutdown(const std::string & ups, long long int delay)  { setInt(ups, "ups.delay.shutdown", delay); }        // CHECKME
-	inline void setUPSdelayStart(const std::string & ups, long long int delay)     { setInt(ups, "ups.delay.start",    delay); }        // CHECKME
-	inline void setVoltage(const std::string & ups, long long int voltage)         { setInt(ups, "voltage",            voltage); }      // CHECKME
+	inline void setADVorder(const std::string & ups, long long int advorder)                  { setInt(ups, "advorder",            advorder); }     // CHECKME
+	inline void setAsem_HB(const std::string & ups, long long int val)                        { setInt(ups, "hb",                  val); }
+	inline void setAsem_LB(const std::string & ups, long long int val)                        { setInt(ups, "lb",                  val); }
+	inline void setBatteryNumber(const std::string & ups, long long int val)                  { setInt(ups, "battery_number",      val); }
+	inline void setBatteryPercentage(const std::string & ups, long long int batt)             { setInt(ups, "batteryPercentage",   batt); }         // CHECKME
+	inline void setBattVoltMult(const std::string & ups, long long int mult)                  { setInt(ups, "battvoltmult",        mult); }         // CHECKME
+	inline void setBaudRate(const std::string & ups, long long int baud_rate)                 { setInt(ups, "baud_rate",           baud_rate); }    // CHECKME
+	inline void setBaudrate(const std::string & ups, long long int baudrate)                  { setInt(ups, "baudrate",            baudrate); }     // CHECKME
+	inline void setCablePower(const std::string & ups, long long int cablepower)              { setInt(ups, "cablepower",          cablepower); }   // CHECKME
+	inline void setChargeTime(const std::string & ups, long long int chargetime)              { setInt(ups, "chargetime",          chargetime); }   // CHECKME
+	inline void setDaysOff(const std::string & ups, long long int daysoff)                    { setInt(ups, "daysoff",             daysoff); }      // CHECKME
+	inline void setDaysWeek(const std::string & ups, long long int daysweek)                  { setInt(ups, "daysweek",            daysweek); }     // CHECKME
+	inline void setDebugMin(const std::string & ups, long long int val)                       { setInt(ups, "debug_min",           val); }
+	inline void setFrequency(const std::string & ups, long long int frequency)                { setInt(ups, "frequency",           frequency); }    // CHECKME
+	inline void setHourOff(const std::string & ups, long long int houroff)                    { setInt(ups, "houroff",             houroff); }      // CHECKME
+	inline void setHourOn(const std::string & ups, long long int houron)                      { setInt(ups, "houron",              houron); }       // CHECKME
+	inline void setI2C_address(const std::string & ups, long long int val)                    { setInt(ups, "i2c_address",         val); }
+	inline void setIdleLoad(const std::string & ups, long long int idleload)                  { setInt(ups, "idleload",            idleload); }     // CHECKME
+	inline void setInputTimeout(const std::string & ups, long long int timeout)               { setInt(ups, "input_timeout",       timeout); }      // CHECKME
+	inline void setInterruptSize(const std::string & ups, long long int val)                  { setInt(ups, "interruptsize",       val); }
+	inline void setLineVoltage(const std::string & ups, long long int linevoltage)            { setInt(ups, "linevoltage",         linevoltage); }  // CHECKME
+	inline void setLoadpercentage(const std::string & ups, long long int load)                { setInt(ups, "loadPercentage",      load); }         // CHECKME
+	inline void setMaxLoad(const std::string & ups, long long int max_load)                   { setInt(ups, "max_load",            max_load); }     // CHECKME
+	inline void setMaxPollsWithoutData(const std::string & ups, long long int val)            { setInt(ups, "max_polls_without_data", val); }
+	inline void setMaxStartDelay(const std::string & ups, long long int delay)                { setInt(ups, "maxstartdelay",       delay); }
+	inline void setMFR(const std::string & ups, long long int mfr)                            { setInt(ups, "mfr",                 mfr); }          // CHECKME
+	inline void setMinCharge(const std::string & ups, long long int mincharge)                { setInt(ups, "mincharge",           mincharge); }    // CHECKME
+	inline void setMinRuntime(const std::string & ups, long long int minruntime)              { setInt(ups, "minruntime",          minruntime); }   // CHECKME
+	inline void setModbus_ByteTimeoutSec(const std::string & ups, long long int val)          { setInt(ups, "mod_byte_to_s",       val); }
+	inline void setModbus_ByteTimeoutUsec(const std::string & ups, long long int val)         { setInt(ups, "mod_byte_to_us",      val); }
+	inline void setModbus_CHRG_addr(const std::string & ups, long long int val)               { setInt(ups, "CHRG_addr",           val); }
+	inline void setModbus_CHRG_noro(const std::string & ups, long long int val)               { setInt(ups, "CHRG_noro",           val); }
+	inline void setModbus_CHRG_regtype(const std::string & ups, long long int val)            { setInt(ups, "CHRG_regtype",        val); }
+	inline void setModbus_DISCHRG_addr(const std::string & ups, long long int val)            { setInt(ups, "DISCHRG_addr",        val); }
+	inline void setModbus_DISCHRG_noro(const std::string & ups, long long int val)            { setInt(ups, "DISCHRG_noro",        val); }
+	inline void setModbus_DISCHRG_regtype(const std::string & ups, long long int val)         { setInt(ups, "DISCHRG_regtype",     val); }
+	inline void setModbus_DataBits(const std::string & ups, long long int val)                { setInt(ups, "databits",            val); }
+	inline void setModbus_DeviceSlaveId(const std::string & ups, long long int val)           { setInt(ups, "dev_slave_id",        val); }
+	inline void setModbus_FSD_addr(const std::string & ups, long long int val)                { setInt(ups, "FSD_addr",            val); }
+	inline void setModbus_FSD_noro(const std::string & ups, long long int val)                { setInt(ups, "FSD_noro",            val); }
+	inline void setModbus_FSD_pulse_duration(const std::string & ups, long long int val)      { setInt(ups, "FSD_pulse_duration",  val); }
+	inline void setModbus_FSD_regtype(const std::string & ups, long long int val)             { setInt(ups, "FSD_regtype",         val); }
+	inline void setModbus_HB_addr(const std::string & ups, long long int val)                 { setInt(ups, "HB_addr",             val); }
+	inline void setModbus_HB_noro(const std::string & ups, long long int val)                 { setInt(ups, "HB_noro",             val); }
+	inline void setModbus_HB_regtype(const std::string & ups, long long int val)              { setInt(ups, "HB_regtype",          val); }
+	inline void setModbus_LB_addr(const std::string & ups, long long int val)                 { setInt(ups, "LB_addr",             val); }
+	inline void setModbus_LB_noro(const std::string & ups, long long int val)                 { setInt(ups, "LB_noro",             val); }
+	inline void setModbus_LB_regtype(const std::string & ups, long long int val)              { setInt(ups, "LB_regtype",          val); }
+	inline void setModbus_OB_addr(const std::string & ups, long long int val)                 { setInt(ups, "OB_addr",             val); }
+	inline void setModbus_OB_noro(const std::string & ups, long long int val)                 { setInt(ups, "OB_noro",             val); }
+	inline void setModbus_OB_regtype(const std::string & ups, long long int val)              { setInt(ups, "OB_regtype",          val); }
+	inline void setModbus_OL_addr(const std::string & ups, long long int val)                 { setInt(ups, "OL_addr",             val); }
+	inline void setModbus_OL_noro(const std::string & ups, long long int val)                 { setInt(ups, "OL_noro",             val); }
+	inline void setModbus_OL_regtype(const std::string & ups, long long int val)              { setInt(ups, "OL_regtype",          val); }
+	inline void setModbus_RB_addr(const std::string & ups, long long int val)                 { setInt(ups, "RB_addr",             val); }
+	inline void setModbus_RB_noro(const std::string & ups, long long int val)                 { setInt(ups, "RB_noro",             val); }
+	inline void setModbus_RB_regtype(const std::string & ups, long long int val)              { setInt(ups, "RB_regtype",          val); }
+	inline void setModbus_ResponseTimeoutMsec(const std::string & ups, long long int val)     { setInt(ups, "response_timeout_ms", val); }
+	inline void setModbus_ResponseTimeoutSec(const std::string & ups, long long int val)      { setInt(ups, "mod_resp_to_s",       val); }
+	inline void setModbus_ResponseTimeoutUsec(const std::string & ups, long long int val)     { setInt(ups, "mod_resp_to_us",      val); }
+	inline void setModbus_RioSlaveId(const std::string & ups, long long int val)              { setInt(ups, "rio_slave_id",        val); }
+	inline void setModbus_SerBaudRate(const std::string & ups, long long int val)             { setInt(ups, "ser_baud_rate",       val); }
+	inline void setModbus_SerDataBit(const std::string & ups, long long int val)              { setInt(ups, "ser_data_bit",        val); }
+	inline void setModbus_SerStopBit(const std::string & ups, long long int val)              { setInt(ups, "ser_stop_bit",        val); }
+	inline void setModbus_SlaveId(const std::string & ups, long long int val)                 { setInt(ups, "slaveid",             val); }
+	inline void setModbus_StopBits(const std::string & ups, long long int val)                { setInt(ups, "stopbits",            val); }
+	inline void setNomBattVolt(const std::string & ups, long long int nombattvolt)            { setInt(ups, "nombattvolt",         nombattvolt); }  // CHECKME
+	inline void setNumOfBytesFromUPS(const std::string & ups, long long int bytes)            { setInt(ups, "numOfBytesFromUPS",   bytes); }        // CHECKME
+	inline void setOffDelay(const std::string & ups, long long int offdelay)                  { setInt(ups, "OffDelay",            offdelay); }     // CHECKME
+	inline void setOffdelay(const std::string & ups, long long int offdelay)                  { setInt(ups, "offdelay",            offdelay); }     // CHECKME
+	inline void setOnDelay(const std::string & ups, long long int ondelay)                    { setInt(ups, "OnDelay",             ondelay); }      // CHECKME
+	inline void setOndelay(const std::string & ups, long long int ondelay)                    { setInt(ups, "ondelay",             ondelay); }      // CHECKME
+	inline void setOnlineDischargeLogThrottleHovercharge(const std::string & ups, long long int val) { setInt(ups, "onlinedischarge_log_throttle_hovercharge", val); }
+	inline void setOnlineDischargeLogThrottleSec(const std::string & ups, long long int val)  { setInt(ups, "onlinedischarge_log_throttle_sec", val); }
+	inline void setOutputPace(const std::string & ups, long long int output_pace)             { setInt(ups, "output_pace",         output_pace); }  // CHECKME
+	inline void setOutputPhaseAngle(const std::string & ups, long long int val)               { setInt(ups, "output_phase_angle",  val); }
+	inline void setPinsShutdownMode(const std::string & ups, long long int val)               { setInt(ups, "pins_shutdown_mode",  val); }
+	inline void setPollFreq(const std::string & ups, long long int pollfreq)                  { setInt(ups, "pollfreq",            pollfreq); }     // CHECKME
+	inline void setPowerUp(const std::string & ups, long long int powerup)                    { setInt(ups, "powerup",             powerup); }      // CHECKME
+	inline void setPrgShut(const std::string & ups, long long int prgshut)                    { setInt(ups, "prgshut",             prgshut); }      // CHECKME
+	inline void setRebootDelay(const std::string & ups, long long int delay)                  { setInt(ups, "rebootdelay",         delay); }        // CHECKME
+	inline void setSDtime(const std::string & ups, long long int sdtime)                      { setInt(ups, "sdtime",              sdtime); }       // CHECKME
+	inline void setSDOrder(const std::string & ups, long long int ord)                        { setInt(ups, "sdorder",             ord); }
+	inline void setSemistaticFreq(const std::string & ups, long long int val)                 { setInt(ups, "semistaticfreq",      val); }
+	inline void setShutdownDelay(const std::string & ups, long long int delay)                { setInt(ups, "shutdown_delay",      delay); }        // CHECKME
+	inline void setShutdownDuration(const std::string & ups, long long int val)               { setInt(ups, "shutdown_duration",   val); }
+	inline void setShutdownTimer(const std::string & ups, long long int val)                  { setInt(ups, "shutdown_timer",      val); }
+	inline void setSlaveAddress(const std::string & ups, long long int val)                   { setInt(ups, "slave_address",       val); }
+	inline void setSnmpRetries(const std::string & ups, long long int val)                    { setInt(ups, "snmp_retries",        val); }
+	inline void setSnmpTimeout(const std::string & ups, long long int val)                    { setInt(ups, "snmp_timeout",        val); }
+	inline void setStartDelay(const std::string & ups, long long int delay)                   { setInt(ups, "startdelay",          delay); }        // CHECKME
+	inline void setTestTime(const std::string & ups, long long int testtime)                  { setInt(ups, "testtime",            testtime); }     // CHECKME
+	inline void setTimeout(const std::string & ups, long long int timeout)                    { setInt(ups, "timeout",             timeout); }      // CHECKME
+	inline void setUPSdelayShutdown(const std::string & ups, long long int delay)             { setInt(ups, "ups.delay.shutdown",  delay); }        // CHECKME
+	inline void setUPSdelayStart(const std::string & ups, long long int delay)                { setInt(ups, "ups.delay.start",     delay); }        // CHECKME
+	inline void setVoltage(const std::string & ups, long long int voltage)                    { setInt(ups, "voltage",             voltage); }      // CHECKME
+	inline void setWaitBeforeReconnect(const std::string & ups, long long int val)            { setInt(ups, "waitbeforereconnect", val); }
+
+	// Items below are "unused" - mostly set in
+	// drivers/nutdrv_qx_masterguard.c
+	inline void setFault1(const std::string & ups, const std::string & val)                   { setStr(ups, "fault_1",             val); }
+	inline void setFault2(const std::string & ups, const std::string & val)                   { setStr(ups, "fault_2",             val); }
+	inline void setFault3(const std::string & ups, const std::string & val)                   { setStr(ups, "fault_3",             val); }
+	inline void setFault4(const std::string & ups, const std::string & val)                   { setStr(ups, "fault_4",             val); }
+	inline void setFault5(const std::string & ups, const std::string & val)                   { setStr(ups, "fault_5",             val); }
+	inline void setInputFaultVoltage(const std::string & ups, const std::string & val)        { setStr(ups, "input_fault_voltage", val); }
+	inline void setNominalCellVoltage(const std::string & ups, const std::string & val)       { setStr(ups, "nominal_cell_voltage",val); }
+	inline void setNumberOfBatteryCells(const std::string & ups, const std::string & val)     { setStr(ups, "number_of_battery_cells", val); }
+	inline void setOutputVoltages(const std::string & ups, const std::string & val)           { setStr(ups, "output_voltages",     val); }
+	inline void setRechargeTime(const std::string & ups, const std::string & val)             { setStr(ups, "recharge_time",       val); }
+	inline void setRuntimeFull(const std::string & ups, const std::string & val)              { setStr(ups, "runtime_full",        val); }
+	inline void setRuntimeHalf(const std::string & ups, const std::string & val)              { setStr(ups, "runtime_half",        val); }
+	inline void setSeries(const std::string & ups, const std::string & val)                   { setStr(ups, "series",              val); }
+
+	// Items below are essentially booleans (expected values
+	// are "enabled/disabled") -- refactoring planned per
+	// https://github.com/networkupstools/nut/issues/2421
+	inline void setAdvancedEcoMode(const std::string & ups, const std::string & val)          { setStr(ups, "advanced_eco_mode",   val); }
+	inline void setAlarmControl(const std::string & ups, const std::string & val)             { setStr(ups, "alarm_control",       val); }
+	inline void setBatteryAlarm(const std::string & ups, const std::string & val)             { setStr(ups, "battery_alarm",       val); }
+	inline void setBatteryOpenStatusCheck(const std::string & ups, const std::string & val)   { setStr(ups, "battery_open_status_check", val); }
+	inline void setBypassAlarm(const std::string & ups, const std::string & val)              { setStr(ups, "bypass_alarm",        val); }
+	inline void setBypassForbidding(const std::string & ups, const std::string & val)         { setStr(ups, "bypass_forbidding",   val); }
+	inline void setBypassWhenOff(const std::string & ups, const std::string & val)            { setStr(ups, "bypass_when_off",     val); }
+	inline void setConstantPhaseAngle(const std::string & ups, const std::string & val)       { setStr(ups, "constant_phase_angle",val); }
+	inline void setConverterMode(const std::string & ups, const std::string & val)            { setStr(ups, "converter_mode",      val); }
+	inline void setEcoMode(const std::string & ups, const std::string & val)                  { setStr(ups, "eco_mode",            val); }
+	inline void setLimitedRuntimeOnBattery(const std::string & ups, const std::string & val)  { setStr(ups, "limited_runtime_on_battery", val); }
+	inline void setSiteFaultDetection(const std::string & ups, const std::string & val)       { setStr(ups, "site_fault_detection",val); }
+
+	/** belkinunv: both a flag (wait for AC power) and value (also wait for charge level) */
 	inline void setWait(const std::string & ups, long long int wait)               { setInt(ups, "wait",               wait); }         // CHECKME
 
-	inline void setNolock(const std::string & ups, bool set = true)         { setStr(ups, "nolock",         bool2str(set)); }
-	inline void setCable(const std::string & ups, bool set = true)          { setStr(ups, "cable",          bool2str(set)); }
-	inline void setDumbTerm(const std::string & ups, bool set = true)       { setStr(ups, "dumbterm",       bool2str(set)); }
-	inline void setExplore(const std::string & ups, bool set = true)        { setStr(ups, "explore",        bool2str(set)); }
-	inline void setFakeLowBatt(const std::string & ups, bool set = true)    { setStr(ups, "fake_lowbatt",   bool2str(set)); }
-	inline void setFlash(const std::string & ups, bool set = true)          { setStr(ups, "flash",          bool2str(set)); }
-	inline void setFullUpdate(const std::string & ups, bool set = true)     { setStr(ups, "full_update",    bool2str(set)); }
-	inline void setLangIDfix(const std::string & ups, bool set = true)      { setStr(ups, "langid_fix",     bool2str(set)); }
-	inline void setLoadOff(const std::string & ups, bool set = true)        { setStr(ups, "load.off",       bool2str(set)); }
-	inline void setLoadOn(const std::string & ups, bool set = true)         { setStr(ups, "load.on",        bool2str(set)); }
-	inline void setNoHang(const std::string & ups, bool set = true)         { setStr(ups, "nohang",         bool2str(set)); }
-	inline void setNoRating(const std::string & ups, bool set = true)       { setStr(ups, "norating",       bool2str(set)); }
-	inline void setNoTransferOIDs(const std::string & ups, bool set = true) { setStr(ups, "notransferoids", bool2str(set)); }
-	inline void setNoVendor(const std::string & ups, bool set = true)       { setStr(ups, "novendor",       bool2str(set)); }
-	inline void setNoWarnNoImp(const std::string & ups, bool set = true)    { setStr(ups, "nowarn_noimp",   bool2str(set)); }
-	inline void setPollOnly(const std::string & ups, bool set = true)       { setStr(ups, "pollonly",       bool2str(set)); }
-	inline void setSilent(const std::string & ups, bool set = true)         { setStr(ups, "silent",         bool2str(set)); }
-	inline void setStatusOnly(const std::string & ups, bool set = true)     { setStr(ups, "status_only",    bool2str(set)); }
-	inline void setSubscribe(const std::string & ups, bool set = true)      { setStr(ups, "subscribe",      bool2str(set)); }
-	inline void setUseCRLF(const std::string & ups, bool set = true)        { setStr(ups, "use_crlf",       bool2str(set)); }
-	inline void setUsePreLF(const std::string & ups, bool set = true)       { setStr(ups, "use_pre_lf",     bool2str(set)); }
+	/** May be a flag or a number; 0 is among valid values (default -1 for unset) */
+	inline void setUsbSetAltInterface(const std::string & ups, long long int val = 0)       { if (val >= 0) { setInt(ups, "usb_set_altinterface", val); } else { remove(ups, "usb_set_altinterface"); } }         // CHECKME
+
+	// NUT specifies these as "hexnum" values (optionally with prefixed 0x but hex anyway)
+	inline void setUsbConfigIndex(const std::string & ups, long long int val)               { setIntHex(ups, "usb_config_index",               val); }         // CHECKME
+	inline void setUsbHidDescIndex(const std::string & ups, long long int val)              { setIntHex(ups, "usb_hid_desc_index",             val); }         // CHECKME
+	inline void setUsbHidRepIndex(const std::string & ups, long long int val)               { setIntHex(ups, "usb_hid_rep_index",              val); }         // CHECKME
+	inline void setUsbHidEndpointIn(const std::string & ups, long long int val)             { setIntHex(ups, "usb_hid_ep_in",                  val); }         // CHECKME
+	inline void setUsbHidEndpointOut(const std::string & ups, long long int val)            { setIntHex(ups, "usb_hid_ep_out",                 val); }         // CHECKME
+
+	inline void setBatteryMax(const std::string & ups, double val)                          { setDouble(ups, "battery_max",        val); }
+	inline void setBatteryMin(const std::string & ups, double val)                          { setDouble(ups, "battery_min",        val); }
+	inline void setCSHackDelay(const std::string & ups, double val)                         { setDouble(ups, "cshdelay",           val); }
+	inline void setMaxBypassFreq(const std::string & ups, double val)                       { setDouble(ups, "max_bypass_freq",    val); }
+	inline void setMaxBypassVolt(const std::string & ups, double val)                       { setDouble(ups, "max_bypass_volt",    val); }
+	inline void setMinBypassFreq(const std::string & ups, double val)                       { setDouble(ups, "min_bypass_freq",    val); }
+	inline void setMinBypassVolt(const std::string & ups, double val)                       { setDouble(ups, "min_bypass_volt",    val); }
+
+	// Flag - if exists then "true"; remove() to "unset" => "false"
+	inline void setCancelShutdown(const std::string & ups, bool set = true) { setFlag(ups, "CS",             set); }
+	inline void setDumbTerm(const std::string & ups, bool set = true)       { setFlag(ups, "dumbterm",       set); }
+	inline void setExplore(const std::string & ups, bool set = true)        { setFlag(ups, "explore",        set); }
+	inline void setFakeLowBatt(const std::string & ups, bool set = true)    { setFlag(ups, "fake_lowbatt",   set); }
+	inline void setFlash(const std::string & ups, bool set = true)          { setFlag(ups, "flash",          set); }
+	inline void setIgnoreLB(const std::string & ups, bool set = true)       { setFlag(ups, "ignorelb",       set); }
+	inline void setNoHang(const std::string & ups, bool set = true)         { setFlag(ups, "nohang",         set); }
+	inline void setNoRating(const std::string & ups, bool set = true)       { setFlag(ups, "norating",       set); }
+	inline void setNoTransferOIDs(const std::string & ups, bool set = true) { setFlag(ups, "notransferoids", set); }
+	inline void setNoVendor(const std::string & ups, bool set = true)       { setFlag(ups, "novendor",       set); }
+	inline void setNoWarnNoImp(const std::string & ups, bool set = true)    { setFlag(ups, "nowarn_noimp",   set); }
+	inline void setOldMAC(const std::string & ups, bool set = true)         { setFlag(ups, "oldmac",         set); }
+	inline void setPollOnly(const std::string & ups, bool set = true)       { setFlag(ups, "pollonly",       set); }
+	inline void setSilent(const std::string & ups, bool set = true)         { setFlag(ups, "silent",         set); }
+	inline void setStatusOnly(const std::string & ups, bool set = true)     { setFlag(ups, "status_only",    set); }	// aka OPTI_MINPOLL
+	inline void setSubscribe(const std::string & ups, bool set = true)      { setFlag(ups, "subscribe",      set); }
+	inline void setUseCRLF(const std::string & ups, bool set = true)        { setFlag(ups, "use_crlf",       set); }
+	inline void setUsePreLF(const std::string & ups, bool set = true)       { setFlag(ups, "use_pre_lf",     set); }
+
+	inline void setNolock(const std::string & ups, bool set = true)         { setBool(ups, "nolock",         set); }
+	inline void setCable(const std::string & ups, bool set = true)          { setBool(ups, "cable",          set); }
+	inline void setFullUpdate(const std::string & ups, bool set = true)     { setBool(ups, "full_update",    set); }
+	inline void setLangIDfix(const std::string & ups, bool set = true)      { setBool(ups, "langid_fix",     set); }
+	inline void setLoadOff(const std::string & ups, bool set = true)        { setBool(ups, "load.off",       set); }
+	inline void setLoadOn(const std::string & ups, bool set = true)         { setBool(ups, "load.on",        set); }
 
 	/** \} */
 
@@ -1077,14 +2239,16 @@ class UpsdUsersConfiguration : public GenericConfiguration
 	/** upsmon mode */
 	typedef enum {
 		UPSMON_UNDEF = 0,  /**< Unknown mode */
-		UPSMON_MASTER,     /**< Master  mode */
-		UPSMON_SLAVE,      /**< Slave   mode */
+		UPSMON_PRIMARY,    /**< Primary   (legacy "Master") mode */
+		UPSMON_SECONDARY,  /**< Secondary (legacy "Slave")  mode */
 	} upsmon_mode_t;
 
 	/** User-specific configuration attributes getters and setters \{ */
 
 	inline std::string getPassword(const std::string & user) const { return getStr(user, "password"); }
 
+	/** Currently valid actions include "SET" and "FSD",
+	 *  but the method does not constrain the values */
 	inline ConfigParamList getActions(const std::string & user) const
 	{
 		ConfigParamList actions;
@@ -1092,6 +2256,8 @@ class UpsdUsersConfiguration : public GenericConfiguration
 		return actions;
 	}
 
+	/** Valid commands are "ALL" or a list of specific commands
+	 *  supported by the device (NUT driver dependent) */
 	inline ConfigParamList getInstantCommands(const std::string & user) const
 	{
 		ConfigParamList cmds;
@@ -1117,6 +2283,9 @@ class UpsdUsersConfiguration : public GenericConfiguration
 	 *
 	 *  \param  mode  Mode
 	 */
+	/* TOTHINK: Do we need a writer (other method, optional parameter
+	 * to this one) for obsolete wordings of the upsmon mode?
+	 * Note: reader in the getter accepts both old and new values. */
 	void setUpsmonMode(upsmon_mode_t mode);
 
 	/** \} */
diff --git a/include/nutipc.hpp b/include/nutipc.hpp
index d668363b3c..56618d6200 100644
--- a/include/nutipc.hpp
+++ b/include/nutipc.hpp
@@ -5,6 +5,10 @@
 
         Author: Vaclav Krpec  <VaclavKrpec@Eaton.com>
 
+    Copyright (C) 2024 NUT Community
+
+        Author: Jim Klimov  <jimklimov+nut@gmail.com>
+
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
@@ -810,7 +814,11 @@ void Signal::HandlerThread<H>::quit()
 
 
 template <class H>
-Signal::HandlerThread<H>::~HandlerThread<H>()
+Signal::HandlerThread<H>::~HandlerThread
+#if (defined __clang__)
+	<H>
+#endif
+()
 #if (defined __cplusplus) && (__cplusplus < 201100)
 	throw(std::runtime_error)
 #endif
diff --git a/include/nutstream.hpp b/include/nutstream.hpp
index 13c9cf76ed..68352942cc 100644
--- a/include/nutstream.hpp
+++ b/include/nutstream.hpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
 	2012	Vaclav Krpec  <VaclavKrpec@Eaton.com>
+	2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
diff --git a/include/nutwriter.hpp b/include/nutwriter.hpp
index b04c44acbb..6d88ca6c09 100644
--- a/include/nutwriter.hpp
+++ b/include/nutwriter.hpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
 	2012	Vaclav Krpec  <VaclavKrpec@Eaton.com>
+	2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -126,7 +127,7 @@ class NutWriter {
 
 
 /**
- *  \brief  NUT configuration writer interface
+ *  \brief  NUT configuration writer interface (generic)
  */
 class NutConfigWriter: public NutWriter {
 	protected:
diff --git a/include/parseconf.h b/include/parseconf.h
index 828a1e09b3..3c8c8851da 100644
--- a/include/parseconf.h
+++ b/include/parseconf.h
@@ -24,15 +24,15 @@
 
 /* Not including nut_stdint.h because this is part of end-user API */
 #if defined HAVE_INTTYPES_H
-	#include <inttypes.h>
+#	include <inttypes.h>
 #endif
 
 #if defined HAVE_STDINT_H
-	#include <stdint.h>
+#	include <stdint.h>
 #endif
 
 #if defined HAVE_LIMITS_H
-	#include <limits.h>
+#	include <limits.h>
 #endif
 
 #ifdef __cplusplus
diff --git a/include/proto.h b/include/proto.h
index f88dd61f1c..68c251a118 100644
--- a/include/proto.h
+++ b/include/proto.h
@@ -24,7 +24,13 @@
 #ifndef NUT_PROTO_H_SEEN
 #define NUT_PROTO_H_SEEN 1
 
-#include "config.h"
+/* "config.h" is generated by autotools and lacks a header guard, so
+ * we use an unambiguously named macro we know we must have, as one.
+ * It must be the first header: be sure to know all about system config.
+ */
+#ifndef NUT_NETVERSION
+# include "config.h"
+#endif
 
 #include "attribute.h"
 
diff --git a/include/state.h b/include/state.h
index 60dc3433fe..9857e4d584 100644
--- a/include/state.h
+++ b/include/state.h
@@ -32,6 +32,8 @@ extern "C" {
 
 #define ST_SOCK_BUF_LEN 512
 
+#include "timehead.h"
+
 #if defined(HAVE_CLOCK_GETTIME) && defined(HAVE_CLOCK_MONOTONIC) && HAVE_CLOCK_GETTIME && HAVE_CLOCK_MONOTONIC
 typedef struct timespec	st_tree_timespec_t;
 #else
diff --git a/include/str.h b/include/str.h
index d7aac249f6..44cd3a667d 100644
--- a/include/str.h
+++ b/include/str.h
@@ -32,7 +32,7 @@ extern "C" {
 /* Some compilers and/or C libraries do not handle printf("%s", NULL) correctly */
 #ifndef NUT_STRARG
 # if (defined REQUIRE_NUT_STRARG) && (REQUIRE_NUT_STRARG == 0)
-#  define NUT_STRARG(x) x
+#  define NUT_STRARG(x) (x)
 # else
 /* Is required, or not defined => err on safe side */
 #  define NUT_STRARG(x) (x?x:"(null)")
diff --git a/include/timehead.h b/include/timehead.h
index 7a5d989a7d..0eeea4bf9b 100644
--- a/include/timehead.h
+++ b/include/timehead.h
@@ -1,8 +1,8 @@
 /* timehead.h - from the autoconf docs: sanely include the right time headers everywhere
 
-   Copyright (C) 2001  Russell Kroll <rkroll@exploits.org>
-	2005	Arnaud Quette <arnaud.quette@free.fr>
-	2020	Jim Klimov <jimklimov@gmail.com>
+   Copyright (C) 2001	Russell Kroll <rkroll@exploits.org>
+	2005	 	Arnaud Quette <arnaud.quette@free.fr>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -44,10 +44,12 @@ extern "C" {
 char * strptime(const char *buf, const char *fmt, struct tm *tm);
 #endif
 
-#ifndef HAVE_LOCALTIME_R
-# ifdef HAVE_LOCALTIME_S
-/* A bit of a silly trick, but should help on MSYS2 builds it seems */
-#  define localtime_r(timer, buf) localtime_s(timer, buf)
+#if !(defined HAVE_LOCALTIME_R && HAVE_LOCALTIME_R) && !(defined HAVE_DECL_LOCALTIME_R && HAVE_DECL_LOCALTIME_R)
+# if (defined HAVE_LOCALTIME_S && HAVE_LOCALTIME_S) || (defined HAVE_DECL_LOCALTIME_S && HAVE_DECL_LOCALTIME_S)
+/* A bit of a silly trick, but should help on MSYS2 builds it seems
+ *  errno_t localtime_s(struct tm *_Tm, const time_t *_Time)
+ */
+#  define localtime_r(timer, buf) (localtime_s(buf, timer) ? NULL : buf)
 # else
 #  include <string.h> /* memcpy */
 static inline struct tm *localtime_r( const time_t *timer, struct tm *buf ) {
@@ -59,9 +61,10 @@ static inline struct tm *localtime_r( const time_t *timer, struct tm *buf ) {
 # endif
 #endif
 
-#ifndef HAVE_GMTIME_R
-# ifdef HAVE_GMTIME_S
-#  define gmtime_r(timer, buf) gmtime_s(timer, buf)
+#if !(defined HAVE_GMTIME_R && HAVE_GMTIME_R) && !(defined HAVE_DECL_GMTIME_R && HAVE_DECL_GMTIME_R)
+# if (defined HAVE_GMTIME_S && HAVE_GMTIME_S) || (defined HAVE_DECL_GMTIME_S && HAVE_DECL_GMTIME_S)
+/* See comment above */
+#  define gmtime_r(timer, buf) (gmtime_s(buf, timer) ? NULL : buf)
 # else
 #  include <string.h> /* memcpy */
 static inline struct tm *gmtime_r( const time_t *timer, struct tm *buf ) {
@@ -73,6 +76,19 @@ static inline struct tm *gmtime_r( const time_t *timer, struct tm *buf ) {
 # endif
 #endif
 
+#if !(defined HAVE_TIMEGM && HAVE_TIMEGM) && !(defined HAVE_DECL_TIMEGM && HAVE_DECL_TIMEGM)
+# if (defined HAVE__MKGMTIME && HAVE__MKGMTIME) || (defined HAVE_DECL__MKGMTIME && HAVE_DECL__MKGMTIME)
+#  define timegm(tm) _mkgmtime(tm)
+# else
+#  ifdef WANT_TIMEGM_FALLBACK
+	/* use an implementation from fallbacks in NUT codebase */
+#   define timegm(tm) timegm_fallback(tm)
+#  else
+#   error "No fallback implementation for timegm"
+#  endif
+# endif
+#endif
+
 #ifdef __cplusplus
 /* *INDENT-OFF* */
 }
diff --git a/indent.sh b/indent.sh
index 0aaf571f32..67cfd72352 100755
--- a/indent.sh
+++ b/indent.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # Filter NUT C source file style to conform to recommendations of
 # https://www.networkupstools.org/docs/developer-guide.chunked/ar01s03.html#_coding_style
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 7d272d8de6..63a0427104 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 EXTRA_DIST = README.adoc
 
diff --git a/m4/ax_c_pragmas.m4 b/m4/ax_c_pragmas.m4
index f2cf78f676..af33afb6a3 100644
--- a/m4/ax_c_pragmas.m4
+++ b/m4/ax_c_pragmas.m4
@@ -146,6 +146,33 @@ dnl ###        [CFLAGS="${CFLAGS_SAVED} -Werror=pragmas -Werror=unknown-warning"
   ]) dnl Special pragma support testing for clang
 
   dnl Test common pragmas for GCC (and compatible) compilers
+  AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wpedantic"],
+    [ax_cv__pragma__gcc__diags_ignored_pedantic],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[void func(void) {
+#pragma GCC diagnostic ignored "-Wpedantic"
+}
+]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_pedantic=yes],
+      [ax_cv__pragma__gcc__diags_ignored_pedantic=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_pedantic" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_PEDANTIC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wpedantic"])
+  ])
+
+  AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wpedantic" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_pedantic_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wpedantic"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_pedantic_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_pedantic_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_pedantic_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_PEDANTIC_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wpedantic" (outside functions)])
+  ])
+
   AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wunused-function"],
     [ax_cv__pragma__gcc__diags_ignored_unused_function],
     [AC_COMPILE_IFELSE(
@@ -161,6 +188,21 @@ dnl ###        [CFLAGS="${CFLAGS_SAVED} -Werror=pragmas -Werror=unknown-warning"
     AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_FUNCTION], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wunused-function"])
   ])
 
+  AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wunused-parameter"],
+    [ax_cv__pragma__gcc__diags_ignored_unused_parameter],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[void func(void) {
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+}
+]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_unused_parameter=yes],
+      [ax_cv__pragma__gcc__diags_ignored_unused_parameter=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_unused_parameter" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_PARAMETER], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wunused-parameter"])
+  ])
+
   AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wdeprecated-declarations"],
     [ax_cv__pragma__gcc__diags_ignored_deprecated_declarations],
     [AC_COMPILE_IFELSE(
@@ -662,6 +704,33 @@ dnl ###        [CFLAGS="${CFLAGS_SAVED} -Werror=pragmas -Werror=unknown-warning"
     AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_STMT_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wextra-semi-stmt" (outside functions)])
   ])
 
+  AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Waddress"],
+    [ax_cv__pragma__gcc__diags_ignored_address],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[void func(void) {
+#pragma GCC diagnostic ignored "-Waddress"
+}
+]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_address=yes],
+      [ax_cv__pragma__gcc__diags_ignored_address=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_address" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ADDRESS], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Waddress"])
+  ])
+
+  AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Waddress" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_address_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Waddress"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_address_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_address_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_address_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ADDRESS_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Waddress" (outside functions)])
+  ])
+
   AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wcast-align"],
     [ax_cv__pragma__gcc__diags_ignored_cast_align],
     [AC_COMPILE_IFELSE(
@@ -689,6 +758,7 @@ dnl ###        [CFLAGS="${CFLAGS_SAVED} -Werror=pragmas -Werror=unknown-warning"
     AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wcast-align" (outside functions)])
   ])
 
+  dnl https://reviews.llvm.org/D134831
   AC_CACHE_CHECK([for pragma GCC diagnostic ignored "-Wcast-function-type-strict"],
     [ax_cv__pragma__gcc__diags_ignored_cast_function_type_strict],
     [AC_COMPILE_IFELSE(
@@ -883,6 +953,90 @@ dnl ###        [CFLAGS="${CFLAGS_SAVED} -Werror=pragmas -Werror=unknown-warning"
     AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wexit-time-destructors" (outside functions)])
   ])
 
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wsuggest-override" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_suggest_override_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wsuggest-override"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_suggest_override_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_suggest_override_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_suggest_override_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wsuggest-override" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wsuggest-destructor-override" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_suggest_destructor_override_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wsuggest-destructor-override"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_suggest_destructor_override_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_suggest_destructor_override_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_suggest_destructor_override_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wsuggest-destructor-override" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wweak-vtables" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_weak_vtables_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wweak-vtables"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_weak_vtables_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_weak_vtables_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_weak_vtables_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wweak-vtables" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_deprecated_dynamic_exception_spec_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_deprecated_dynamic_exception_spec_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_deprecated_dynamic_exception_spec_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_deprecated_dynamic_exception_spec_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wextra-semi" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_extra_semi_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wextra-semi"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_extra_semi_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_extra_semi_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_extra_semi_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wextra-semi" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wold-style-cast" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_old_style_cast_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wold-style-cast"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_old_style_cast_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_old_style_cast_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_old_style_cast_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wold-style-cast" (outside functions)])
+  ])
+
+  AC_CACHE_CHECK([for C++ pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant" (outside functions)],
+    [ax_cv__pragma__gcc__diags_ignored_zero_as_null_pointer_constant_besidefunc],
+    [AC_COMPILE_IFELSE(
+      [AC_LANG_PROGRAM([[#pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant"]], [])],
+      [ax_cv__pragma__gcc__diags_ignored_zero_as_null_pointer_constant_besidefunc=yes],
+      [ax_cv__pragma__gcc__diags_ignored_zero_as_null_pointer_constant_besidefunc=no]
+    )]
+  )
+  AS_IF([test "$ax_cv__pragma__gcc__diags_ignored_zero_as_null_pointer_constant_besidefunc" = "yes"],[
+    AC_DEFINE([HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ZERO_AS_NULL_POINTER_CONSTANT_BESIDEFUNC], 1, [define if your compiler has #pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant" (outside functions)])
+  ])
+
   AC_LANG_POP([C++])
 
   dnl # Meta-macros for simpler use-cases where we pick
@@ -1040,7 +1194,34 @@ return 0;
   )
   unset myWARN_CFLAGS
 
-  AS_IF([test "$ax_cv__printf_string_null" = "yes"],[
+  NUT_ARG_ENABLE([NUT_STRARG-always],
+    [Enable NUT_STRARG macro to handle NULL string printing even if system libraries seem to support it natively],
+    [auto])
+
+  dnl gcc-13.2.0 and gcc-13.3.0 were seen to complain about
+  dnl alleged formatting string overflow (seems like a false
+  dnl positive in that case). Require the full macro there
+  dnl by default.
+  dnl AC_MSG_NOTICE([CC_VERSION='$CC_VERSION'])
+  AS_IF([test x"$nut_enable_NUT_STRARG_always" = xauto], [
+    nut_enable_NUT_STRARG_always=no
+    AS_IF([test "${CLANGCC}" = "yes"], [
+        true dnl no-op at the moment
+dnl        AS_CASE(["$CC_VERSION"],
+dnl            [*" "18.*], [nut_enable_NUT_STRARG_always=yes]
+dnl        )
+        ],[
+        AS_IF([test "${GCC}" = "yes"], [
+            AS_CASE(["$CC_VERSION"],
+                [*" "13.*], [nut_enable_NUT_STRARG_always=yes]
+            )
+        ])
+    ])
+    AS_IF([test x"$nut_enable_NUT_STRARG_always" = xyes],
+        [AC_MSG_NOTICE([Automatically enabled NUT_STRARG-always due to compiler version used])])
+  ])
+
+  AS_IF([test "$ax_cv__printf_string_null" = "yes" && test x"$nut_enable_NUT_STRARG_always" != xyes],[
     AM_CONDITIONAL([REQUIRE_NUT_STRARG], [false])
     AC_DEFINE([REQUIRE_NUT_STRARG], [0],
       [Define to 0 if your libc can printf("%s", NULL) sanely, or to 1 if your libc requires workarounds to print NULL values.])
diff --git a/m4/ax_realpath_lib.m4 b/m4/ax_realpath_lib.m4
new file mode 100644
index 0000000000..d57de269ff
--- /dev/null
+++ b/m4/ax_realpath_lib.m4
@@ -0,0 +1,207 @@
+dnl Resolve real path (if we can) to a library file that would be used
+dnl by gcc/clang compatible toolkit. Relies on AX_REALPATH macro and
+dnl may benefit from a REALPATH envvar pointing to a command-line tool
+dnl (otherwise m4/shell implementation gets used), and NUT_COMPILER_FAMILY.
+dnl Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+dnl Licensed under the terms of GPLv2 or newer.
+
+dnl Calling script is welcome to pre-detect external REALPATH implementation,
+dnl otherwise shell implementation would be used (hopefully capable enough):
+dnl AC_CHECK_PROGS([REALPATH], [realpath], [])
+
+AC_DEFUN([AX_REALPATH_LIB_PREREQ],
+[
+if test -z "${nut_ax_realpath_lib_prereq_seen}"; then
+    nut_ax_realpath_lib_prereq_seen=yes
+
+    AC_REQUIRE([NUT_COMPILER_FAMILY])dnl
+    AS_CASE(["${target_os}"],
+        [*mingw*], [
+            AS_IF([test x"${DLLTOOL-}" = x],
+                [AC_CHECK_TOOLS([DLLTOOL], [dlltool dlltool.exe], [false])])
+            AS_IF([test x"${OBJDUMP-}" = x],
+                [AC_CHECK_TOOLS([OBJDUMP], [objdump objdump.exe], [false])])
+            dnl # Assuming mingw (sourceware) x86_64-w64-mingw32-ld or similar
+            AS_IF([test x"${LD-}" = x],
+                [AC_CHECK_TOOLS([LD], [ld ld.exe], [false])])
+        ],
+        [*darwin*], [
+            dnl # Can be a non-GNU ld
+            AS_IF([test x"${LD-}" = x],
+                [AC_CHECK_TOOLS([LD], [ld], [false])])
+        ]
+    )
+fi
+])
+
+AC_DEFUN([AX_REALPATH_LIB],
+[
+    dnl # resolve libname - #1 value (not quoted by caller) if we can;
+    dnl # save into varname #2.
+    dnl # In case of problems return #3 (optional, defaults to empty).
+    AC_REQUIRE([AX_REALPATH_LIB_PREREQ])dnl
+
+    AS_IF([test x"$1" = x], [AC_MSG_ERROR([Bad call to REALPATH_LIB macro (arg1)])])
+    AS_IF([test x"$2" = x], [AC_MSG_ERROR([Bad call to REALPATH_LIB macro (arg2)])])
+
+    AS_IF([test "x$GCC" = xyes -o "x$CLANGCC" = xyes], [
+        myLIBNAME="$1"
+        AS_CASE(["${myLIBNAME}"],
+            [-l*], [myLIBNAME="`echo "$myLIBNAME" | sed 's/^-l/lib/'`"]
+        )
+
+        dnl # Primarily we care to know dynamically linked (shared object)
+        dnl # files, so inject the extension to the presumed base name
+        AS_CASE(["${myLIBNAME}"],
+            [*.so*|*.a|*.o|*.lo|*.la|*.dll|*.dll.a|*.lib|*.dylib|*.sl], [],
+            [
+                AS_CASE(["${target_os}"],
+                    [*mingw*],  [myLIBNAME="${myLIBNAME}.dll"],
+                    [*darwin*], [myLIBNAME="${myLIBNAME}.dylib"],
+                    [*hpux*|*hp?ux*], [
+                                 dnl # See detailed comments in nut_platform.h
+                                 myLIBNAME="${myLIBNAME}.sl"
+                                ],[myLIBNAME="${myLIBNAME}.so"])
+            ]
+        )
+
+        AS_CASE(["${myLIBNAME}"],
+            [lib*], [
+                dnl Alas, the portable solution with sed is to avoid
+                dnl parentheses and pipe chars, got too many different
+                dnl ways to escape them in the wild
+                myLIBNAME_LD="`echo "$myLIBNAME" | sed -e 's/^lib/-l/' -e 's/\.dll$//' -e 's/\.dll\.a$//' -e 's/\.a$//' -e 's/\.o$//' -e 's/\.la$//' -e 's/\.lo$//' -e 's/\.lib$//' -e 's/\.dylib$//' -e 's/\.so\..*$//' -e 's/\.so//' -e 's/\.sl\..*$//' -e 's/\.sl//'`"
+            ], [myLIBNAME_LD="-l$myLIBNAME"]    dnl best-effort...
+        )
+
+        AC_MSG_CHECKING([for real path to $1 (re-parsed as ${myLIBNAME} likely file name / ${myLIBNAME_LD} linker arg)])
+        myLIBPATH=""
+        AS_CASE(["${target_os}"],
+            [*mingw*], [
+                AS_IF([test x"${LD}" != x -a x"${LD}" != xfalse -a x"${DLLTOOL}" != x -a x"${DLLTOOL}" != xfalse], [
+                    dnl Expected output (Linux mingw cross-build) ends like:
+                    dnl   ==================================================
+                    dnl   x86_64-w64-mingw32-ld: mode i386pep
+                    dnl   attempt to open /usr/x86_64-w64-mingw32/lib/libnetsnmp.dll.a succeeded
+                    dnl   /usr/x86_64-w64-mingw32/lib/libnetsnmp.dll.a
+                    dnl ...which we then resolve with dlltool into a libnetsnmp-40.dll
+                    dnl and finally find one in /usr/x86_64-w64-mingw32/bin/libnetsnmp-40.dll
+                    dnl (note the version number embedded into base name).
+                    { myLIBPATH="`$LD --verbose -Bdynamic ${myLIBNAME_LD} | grep -wi dll | tail -1`" \
+                    && test -n "${myLIBPATH}" && test -s "${myLIBPATH}" ; } \
+                    || { myLIBPATH="`$LD $LDFLAGS $LIBS --verbose -Bdynamic ${myLIBNAME_LD} | grep -wi dll | tail -1`" \
+                    && test -n "${myLIBPATH}" && test -s "${myLIBPATH}" ; } \
+                    || myLIBPATH=""
+
+                    dnl Resolve dynamic library "internal" name from its stub, if needed
+                    AS_CASE(["${myLIBPATH}"],
+                        [*.dll.a], [
+                            myLIBPATH="`$DLLTOOL -I "${myLIBPATH}"`" || myLIBPATH=""
+                            ]
+                    )
+
+                    dnl Internal name may be just that, with no path info
+                    AS_CASE(["${myLIBPATH}"],
+                        [*/*], [],
+                        [
+                            for D in \
+                                "/usr/${target}/bin" \
+                                "/usr/${target}/lib" \
+                                "${MSYSTEM_PREFIX}/bin" \
+                                "${MSYSTEM_PREFIX}/lib" \
+                                "${MINGW_PREFIX}/bin" \
+                                "${MINGW_PREFIX}/lib" \
+                                `${CC} --print-search-dirs 2>/dev/null | grep libraries: | sed 's,^libraries: *=/,/,'` \
+                            ; do
+                                if test -s "$D/${myLIBPATH}" 2>/dev/null ; then
+                                    myLIBPATH="$D/${myLIBPATH}"
+                                    break
+                                fi
+                            done
+                            unset D
+                        ]
+                    )
+                ])
+            ], [ dnl # POSIX/MacOS builds
+                { myLIBPATH="`${CC} --print-file-name="$myLIBNAME"`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                || { myLIBPATH="`${CC} $CFLAGS --print-file-name="$myLIBNAME"`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                || { myLIBPATH="`${CC} $CFLAGS $LDFLAGS $LIBS --print-file-name="$myLIBNAME"`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                || myLIBPATH=""
+            ]
+        )
+
+        AS_IF([test -z "${myLIBPATH}" && test x"${LD}" != x -a x"${LD}" != xfalse], [
+            AS_CASE(["${target_os}"],
+                [*darwin*], [
+                    dnl Try MacOS-style LD as fallback; expecting strings like
+                    dnl   ld: warning: /usr/local/lib/libneon.dylib, ignoring unexpected dylib file
+                    my_uname_m="`uname -m`"
+                    { myLIBPATH="`${LD} -dynamic -r -arch "${target_cpu}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                    || { myLIBPATH="`${LD} $LDFLAGS -dynamic -r -arch "${target_cpu}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                    || { myLIBPATH="`${LD} $LDFLAGS $LIBS -dynamic -r -arch "${target_cpu}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                    || if test x"${target_cpu}" != x"${my_uname_m}" ; then
+                        { myLIBPATH="`${LD} -dynamic -r -arch "${my_uname_m}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                        || { myLIBPATH="`${LD} $LDFLAGS -dynamic -r -arch "${my_uname_m}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                        || { myLIBPATH="`${LD} $LDFLAGS $LIBS -dynamic -r -arch "${my_uname_m}" -search_dylibs_first "${myLIBNAME_LD}" 2>&1 | grep -w dylib | sed 's/^@<:@^\/@:>@*\(\/.*\.dylib\),.*$/\1/'`" && test -n "$myLIBPATH" && test -s "$myLIBPATH" ; } \
+                        || myLIBPATH=""
+                    else
+                        myLIBPATH=""
+                    fi
+                    rm -f a.out 2>/dev/null || true
+                    unset my_uname_m
+                ]
+            )
+        ])
+
+        AS_IF([test -n "${myLIBPATH}" && test -s "${myLIBPATH}"], [
+            AC_MSG_RESULT([initially '${myLIBPATH}'])
+
+            AC_MSG_CHECKING([whether the file is a "GNU ld script" and not a binary])
+            AS_IF([LANG=C LC_ALL=C file "${myLIBPATH}" | grep -Ei '(ascii|text)' && grep -w GROUP "${myLIBPATH}" >/dev/null], [
+                # dnl e.g. # cat /usr/lib/x86_64-linux-gnu/libusb.so
+                # dnl    /* GNU ld script.  */
+                # dnl    GROUP ( /lib/x86_64-linux-gnu/libusb-0.1.so.4.4.4 )
+                # dnl Note that spaces around parentheses vary, more keywords
+                # dnl may be present in a group (e.g. AS_NEEDED), and comment
+                # dnl strings are inconsistent (useless to match by).
+                AC_MSG_RESULT([yes, iterate further])
+                myLIBPATH_LDSCRIPT="`grep -w GROUP "${myLIBPATH}" | sed 's,^.*GROUP *( *\(/@<:@^ @:>@*\.so@<:@^ @:>@*\)@<:@^0-9a-zA-Z_.-@:>@.*$,\1,'`"
+                AS_IF([test -n "${myLIBPATH_LDSCRIPT}" && test -s "${myLIBPATH_LDSCRIPT}"], [
+                    AC_MSG_NOTICE([will dig into ${myLIBPATH_LDSCRIPT}])
+
+                    dnl # See detailed comments just below
+                    myLIBPATH_REAL="${myLIBPATH_LDSCRIPT}"
+                    AX_REALPATH([${myLIBPATH_LDSCRIPT}], [myLIBPATH_REAL])
+                ], [
+                    AC_MSG_NOTICE([could not determine a further path name, will use what we have])
+
+                    dnl # See detailed comments just below
+                    myLIBPATH_REAL="${myLIBPATH}"
+                    AX_REALPATH([${myLIBPATH}], [myLIBPATH_REAL])
+                ])
+            ],[
+                AC_MSG_RESULT([no, seems like a normal binary])
+
+                dnl # Resolving the directory location is a nice bonus
+                dnl # (usually the paths are relative to toolkit and ugly,
+                dnl # though maybe arguably portable with regard to symlinks).
+                dnl # The primary goal is to resolve the actual library file
+                dnl # name like "libnetsnmp.so.1.2.3", so we can preferentially
+                dnl # try to dlopen() it on a system with a packaged footprint
+                dnl # that does not serve short (developer-friendly) links like
+                dnl # "libnetsnmp.so".
+                myLIBPATH_REAL="${myLIBPATH}"
+                AX_REALPATH([${myLIBPATH}], [myLIBPATH_REAL])
+            ])
+
+            AC_MSG_RESULT(${myLIBPATH_REAL})
+            $2="${myLIBPATH_REAL}"
+        ],[
+            AC_MSG_RESULT([not found])
+            $2="$3"
+        ])
+    ],
+    [AC_MSG_WARN([Compiler not detected as GCC/CLANG-compatible, skipping REALPATH_LIB($1)])
+     $2="$3"
+    ])
+])
diff --git a/m4/nut_check_aspell.m4 b/m4/nut_check_aspell.m4
index dbccd27878..4515821add 100644
--- a/m4/nut_check_aspell.m4
+++ b/m4/nut_check_aspell.m4
@@ -114,7 +114,7 @@ if test -z "${nut_have_aspell_seen}"; then
 		AS_IF([test -n "$ASPELL_FILTER_TEX_PATH" -a -d "$ASPELL_FILTER_TEX_PATH"], [ASPELL_NUT_TEXMODE_ARGS="--filter-path='${ASPELL_FILTER_TEX_PATH}' ${ASPELL_NUT_TEXMODE_ARGS}"])
 		ASPELL_NUT_COMMON_ARGS="-d en -a"
 		dnl Using "eval" to handle quotes, in case of funny paths
-		out0="`LANG=C; LC_ALL=C; export LANG; export LC_ALL; exec -- 2>&1; set -x; echo test | eval ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS}`"; res0=$?
+		out0="`LANG=C; LC_ALL=C; export LANG; export LC_ALL; ( set -x; echo test | eval ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS} ) 2>&1`"; res0=$?
 		AS_IF([test x"$res0" != x0], [
 			AC_MSG_NOTICE([FAILED CMD: ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS}])
 			AC_MSG_NOTICE([aspell result ($res0) and output: $out0])
@@ -126,7 +126,7 @@ if test -z "${nut_have_aspell_seen}"; then
 				AC_MSG_RESULT(no)
 				AC_MSG_CHECKING([if detected aspell configuration works with built-in paths (tweaked one finds wrong binary modules)])
 				ASPELL_NUT_TEXMODE_ARGS="-t"
-				out0="`LANG=C; LC_ALL=C; export LANG; export LC_ALL; exec -- 2>&1; set -x; echo test | eval ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS}`"; res0=$?
+				out0="`LANG=C; LC_ALL=C; export LANG; export LC_ALL; ( set -x; echo test | eval ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS} ) 2>&1`"; res0=$?
 				AS_IF([test x"$res0" = x0], [ASPELL_FILTER_TEX_PATH=""], [
 					AC_MSG_NOTICE([FAILED CMD: ${ASPELL} ${ASPELL_NUT_TEXMODE_ARGS} ${ASPELL_NUT_COMMON_ARGS}])
 					AC_MSG_NOTICE([aspell result ($res0) and output: $out0])
diff --git a/m4/nut_check_bool.m4 b/m4/nut_check_bool.m4
new file mode 100644
index 0000000000..f77d345fbc
--- /dev/null
+++ b/m4/nut_check_bool.m4
@@ -0,0 +1,378 @@
+dnl # For the sake of portability, check if the system offers a "bool" or a
+dnl # "bool_t" type, and "true"/"false" values for it, and try to determine
+dnl # how exactly these are spelled and implemented. For consumers in the
+dnl # codebase, this plays along with "includes/nut_bool.h" header.
+dnl # Ideally the <stdbool.h> just exists and provides reasonable types and
+dnl # values (all lower-case), per the standard, which we would just alias
+dnl # as "nut_bool_t" and use.
+dnl # See also https://en.cppreference.com/w/cpp/header/cstdbool for more
+dnl # info about what should be available where per standard approach.
+
+dnl # Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+
+AC_DEFUN([NUT_CHECK_BOOL],
+[
+if test -z "${nut_check_bool_seen}"; then
+    nut_check_bool_seen="yes"
+
+    AC_MSG_NOTICE([Checking below whether bool types are provided by system headers and how])
+
+    AC_LANG_PUSH([C++])
+    AC_CHECK_HEADERS_ONCE([cstdbool])
+    AC_LANG_POP([C++])
+
+    AC_LANG_PUSH([C])
+
+    dnl # Check for existing definition of boolean type (should be stdbool.h, but...)
+    AC_CHECK_HEADERS_ONCE([stdbool.h])
+
+    myINCLUDE_STDBOOL="
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#endif
+"
+
+    dnl # Below we would check for C99 built-in "_Bool", and for "bool",
+    dnl # "boolean" and/or "bool_t" type names with various spellings
+    dnl # that may come from headers like <stdbool.h>
+
+    FOUND__BOOL_TYPE=""
+    FOUND__BOOL_IMPLEM_STR=""
+    dnl # _bool
+    HAVE__BOOL_TYPE_LOWERCASE=false
+    dnl # _BOOL
+    HAVE__BOOL_TYPE_UPPERCASE=false
+    dnl # _Bool
+    HAVE__BOOL_TYPE_CAMELCASE=false
+
+    FOUND_BOOL_TYPE=""
+    FOUND_BOOL_IMPLEM_STR=""
+    dnl # bool
+    HAVE_BOOL_TYPE_LOWERCASE=false
+    dnl # BOOL
+    HAVE_BOOL_TYPE_UPPERCASE=false
+    dnl # Bool
+    HAVE_BOOL_TYPE_CAMELCASE=false
+
+    FOUND_BOOLEAN_TYPE=""
+    FOUND_BOOLEAN_IMPLEM_STR=""
+    dnl # boolean
+    HAVE_BOOLEAN_TYPE_LOWERCASE=false
+    dnl # BOOLEAN
+    HAVE_BOOLEAN_TYPE_UPPERCASE=false
+    dnl # Boolean
+    HAVE_BOOLEAN_TYPE_CAMELCASE=false
+
+    FOUND_BOOL_T_TYPE=""
+    FOUND_BOOL_T_IMPLEM_STR=""
+    dnl # bool_t
+    HAVE_BOOL_T_TYPE_LOWERCASE=false
+    dnl # BOOL_T
+    HAVE_BOOL_T_TYPE_UPPERCASE=false
+    dnl # Bool_t?
+    HAVE_BOOL_T_TYPE_CAMELCASE=false
+
+    FOUND__BOOL_VALUE_TRUE=""
+    FOUND__BOOL_VALUE_FALSE=""
+    dnl # true/false
+    HAVE__BOOL_VALUE_LOWERCASE=false
+    dnl # TRUE/FALSE
+    HAVE__BOOL_VALUE_UPPERCASE=false
+    dnl # True/False
+    HAVE__BOOL_VALUE_CAMELCASE=false
+
+    FOUND_BOOL_VALUE_TRUE=""
+    FOUND_BOOL_VALUE_FALSE=""
+    HAVE_BOOL_VALUE_LOWERCASE=false
+    HAVE_BOOL_VALUE_UPPERCASE=false
+    HAVE_BOOL_VALUE_CAMELCASE=false
+
+    FOUND_BOOLEAN_VALUE_TRUE=""
+    FOUND_BOOLEAN_VALUE_FALSE=""
+    HAVE_BOOLEAN_VALUE_LOWERCASE=false
+    HAVE_BOOLEAN_VALUE_UPPERCASE=false
+    HAVE_BOOLEAN_VALUE_CAMELCASE=false
+
+    FOUND_BOOL_T_VALUE_TRUE=""
+    FOUND_BOOL_T_VALUE_FALSE=""
+    HAVE_BOOL_T_VALUE_LOWERCASE=false
+    HAVE_BOOL_T_VALUE_UPPERCASE=false
+    HAVE_BOOL_T_VALUE_CAMELCASE=false
+
+    HAVE__BOOL_IMPLEM_MACRO=false
+    HAVE__BOOL_IMPLEM_INT=false
+    HAVE__BOOL_IMPLEM_ENUM=false
+
+    HAVE_BOOL_IMPLEM_MACRO=false
+    HAVE_BOOL_IMPLEM_INT=false
+    HAVE_BOOL_IMPLEM_ENUM=false
+
+    HAVE_BOOLEAN_IMPLEM_MACRO=false
+    HAVE_BOOLEAN_IMPLEM_INT=false
+    HAVE_BOOLEAN_IMPLEM_ENUM=false
+
+    HAVE_BOOL_T_IMPLEM_MACRO=false
+    HAVE_BOOL_T_IMPLEM_INT=false
+    HAVE_BOOL_T_IMPLEM_ENUM=false
+
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [_bool b])], [HAVE__BOOL_TYPE_LOWERCASE=true; FOUND__BOOL_TYPE="_bool"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [_BOOL b])], [HAVE__BOOL_TYPE_UPPERCASE=true; FOUND__BOOL_TYPE="_BOOL"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [_Bool b])], [HAVE__BOOL_TYPE_CAMELCASE=true; FOUND__BOOL_TYPE="_Bool"])
+
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [bool b])], [HAVE_BOOL_TYPE_LOWERCASE=true; FOUND_BOOL_TYPE="bool"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [BOOL b])], [HAVE_BOOL_TYPE_UPPERCASE=true; FOUND_BOOL_TYPE="BOOL"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [Bool b])], [HAVE_BOOL_TYPE_CAMELCASE=true; FOUND_BOOL_TYPE="Bool"])
+
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [boolean b])], [HAVE_BOOLEAN_TYPE_LOWERCASE=true; FOUND_BOOLEAN_TYPE="boolean"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [BOOLEAN b])], [HAVE_BOOLEAN_TYPE_UPPERCASE=true; FOUND_BOOLEAN_TYPE="BOOLEAN"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [Boolean b])], [HAVE_BOOLEAN_TYPE_CAMELCASE=true; FOUND_BOOLEAN_TYPE="Boolean"])
+
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [bool_t b])], [HAVE_BOOL_T_TYPE_LOWERCASE=true; FOUND_BOOL_T_TYPE="bool_t"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [BOOL_T b])], [HAVE_BOOL_T_TYPE_UPPERCASE=true; FOUND_BOOL_T_TYPE="BOOL_T"])
+    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [Bool_t b])], [HAVE_BOOL_T_TYPE_CAMELCASE=true; FOUND_BOOL_T_TYPE="Bool_t"])
+
+    AS_IF([test x"${FOUND__BOOL_TYPE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND__BOOL_TYPE} bT = true, bF = false])], [HAVE__BOOL_VALUE_LOWERCASE=true; FOUND__BOOL_VALUE_TRUE="true"; FOUND__BOOL_VALUE_FALSE="false"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND__BOOL_TYPE} bT = TRUE, bF = FALSE])], [HAVE__BOOL_VALUE_UPPERCASE=true; FOUND__BOOL_VALUE_TRUE="TRUE"; FOUND__BOOL_VALUE_FALSE="FALSE"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND__BOOL_TYPE} bT = True, bF = False])], [HAVE__BOOL_VALUE_CAMELCASE=true; FOUND__BOOL_VALUE_TRUE="True"; FOUND__BOOL_VALUE_FALSE="False"])
+    ])
+
+    AS_IF([test x"${FOUND_BOOL_TYPE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_TYPE} bT = true, bF = false])], [HAVE_BOOL_VALUE_LOWERCASE=true; FOUND_BOOL_VALUE_TRUE="true"; FOUND_BOOL_VALUE_FALSE="false"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_TYPE} bT = TRUE, bF = FALSE])], [HAVE_BOOL_VALUE_UPPERCASE=true; FOUND_BOOL_VALUE_TRUE="TRUE"; FOUND_BOOL_VALUE_FALSE="FALSE"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_TYPE} bT = True, bF = False])], [HAVE_BOOL_VALUE_CAMELCASE=true; FOUND_BOOL_VALUE_TRUE="True"; FOUND_BOOL_VALUE_FALSE="False"])
+    ])
+
+    AS_IF([test x"${FOUND_BOOLEAN_TYPE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOLEAN_TYPE} bT = true, bF = false])], [HAVE_BOOLEAN_VALUE_LOWERCASE=true; FOUND_BOOLEAN_VALUE_TRUE="true"; FOUND_BOOL_VALUE_FALSE="false"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOLEAN_TYPE} bT = TRUE, bF = FALSE])], [HAVE_BOOLEAN_VALUE_UPPERCASE=true; FOUND_BOOLEAN_VALUE_TRUE="TRUE"; FOUND_BOOL_VALUE_FALSE="FALSE"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOLEAN_TYPE} bT = True, bF = False])], [HAVE_BOOLEAN_VALUE_CAMELCASE=true; FOUND_BOOLEAN_VALUE_TRUE="True"; FOUND_BOOL_VALUE_FALSE="False"])
+    ])
+
+    AS_IF([test x"${FOUND_BOOL_T_TYPE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_T_TYPE} b = true, bF = false])], [HAVE_BOOL_T_VALUE_LOWERCASE=true; FOUND_BOOL_T_VALUE_TRUE="true"; FOUND_BOOL_T_VALUE_FALSE="false"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_T_TYPE} b = TRUE, bF = FALSE])], [HAVE_BOOL_T_VALUE_UPPERCASE=true; FOUND_BOOL_T_VALUE_TRUE="TRUE"; FOUND_BOOL_T_VALUE_FALSE="FALSE"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [${FOUND_BOOL_T_TYPE} b = True, bF = False])], [HAVE_BOOL_T_VALUE_CAMELCASE=true; FOUND_BOOL_T_VALUE_TRUE="True"; FOUND_BOOL_T_VALUE_FALSE="False"])
+    ])
+
+    dnl # FIXME: Some more diligent checks for signed/unsigned int/char/...
+    dnl #  type details? e.g. via sizeof, assignment to negatives, etc.
+    AS_IF([test x"${FOUND__BOOL_TYPE}" = x && test x"${FOUND_BOOL_TYPE}" = x && test x"${FOUND_BOOLEAN_TYPE}" = x && test x"${FOUND_BOOL_T_TYPE}" = x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [int bT = true, bF = false])], [FOUND_BOOL_TYPE="int"; HAVE_BOOL_VALUE_LOWERCASE=true; FOUND_BOOL_VALUE_TRUE="true"; FOUND_BOOL_VALUE_FALSE="false"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [int bT = TRUE, bF = FALSE])], [FOUND_BOOL_TYPE="int"; HAVE_BOOL_VALUE_UPPERCASE=true; FOUND_BOOL_VALUE_TRUE="TRUE"; FOUND_BOOL_VALUE_FALSE="FALSE"])
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [int bT = True, bF = False])], [FOUND_BOOL_TYPE="int"; HAVE_BOOL_VALUE_CAMELCASE=true; FOUND_BOOL_VALUE_TRUE="True"; FOUND_BOOL_VALUE_FALSE="False"])
+    ])
+
+    dnl # Assume there are only 3 implementation options we can discern here
+
+    dnl ####################################################################
+
+    AS_IF([test x"${FOUND__BOOL_TYPE}" != x && test x"${FOUND__BOOL_VALUE_TRUE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+#ifndef ${FOUND__BOOL_VALUE_TRUE}
+#error "${FOUND__BOOL_VALUE_TRUE} is not a macro
+#endif
+#ifndef ${FOUND__BOOL_VALUE_FALSE}
+#error "${FOUND__BOOL_VALUE_FALSE} is not a macro
+#endif
+    ])], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND__BOOL_TYPE} bT = ${FOUND__BOOL_VALUE_TRUE};
+bT = 42
+    ])], [HAVE__BOOL_IMPLEM_INT=true; FOUND__BOOL_IMPLEM="number"], [HAVE__BOOL_IMPLEM_ENUM=true; FOUND__BOOL_IMPLEM="enum"])
+    ], [HAVE__BOOL_IMPLEM_MACRO=true; FOUND__BOOL_IMPLEM="macro"])
+
+            dnl # Final check
+            AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND__BOOL_TYPE} b = ${FOUND__BOOL_VALUE_TRUE};
+int ret = 0;
+
+if (!(!b == ${FOUND__BOOL_VALUE_FALSE})) ret = 1;
+if (!(b  != ${FOUND__BOOL_VALUE_FALSE})) ret = 2;
+if (!(!b != ${FOUND__BOOL_VALUE_TRUE}))  ret = 3;
+if (!b) ret = 4;
+if (ret)
+    return ret
+/* no ";return 0;" here - autoconf adds one */
+            ])],
+            [ dnl # All tests passed, remember this
+                    AC_MSG_NOTICE([Detected a semantically usable "_Bool"-like type name ${FOUND__BOOL_TYPE} implemented as ${FOUND__BOOL_IMPLEM} with boolean values '${FOUND__BOOL_VALUE_TRUE}' and '${FOUND__BOOL_VALUE_FALSE}'])
+                    AC_DEFINE_UNQUOTED([FOUND__BOOL_TYPE],        [${FOUND__BOOL_TYPE}], [C spelling of _Bool type])
+                    AC_DEFINE_UNQUOTED([FOUND__BOOL_IMPLEM_STR],  ["${FOUND__BOOL_IMPLEM}"], [String spelling of _Bool type implementation])
+                    AC_DEFINE_UNQUOTED([FOUND__BOOL_VALUE_TRUE],  [${FOUND__BOOL_VALUE_TRUE}], [C spelling of _Bool type true value])
+                    AC_DEFINE_UNQUOTED([FOUND__BOOL_VALUE_FALSE], [${FOUND__BOOL_VALUE_FALSE}], [C spelling of _Bool type false value])
+
+                    AS_IF([${HAVE__BOOL_TYPE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_TYPE_LOWERCASE], [1], [Name of ${FOUND__BOOL_TYPE} is defined as lower-case token])])
+                    AS_IF([${HAVE__BOOL_TYPE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_TYPE_UPPERCASE], [1], [Name of ${FOUND__BOOL_TYPE} is defined as upper-case token])])
+                    AS_IF([${HAVE__BOOL_TYPE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_TYPE_CAMELCASE], [1], [Name of ${FOUND__BOOL_TYPE} is defined as camel-case token])])
+
+                    AS_IF([${HAVE__BOOL_VALUE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_VALUE_LOWERCASE], [1], [Boolean values of ${FOUND__BOOL_TYPE} are defined as lower-case tokens])])
+                    AS_IF([${HAVE__BOOL_VALUE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_VALUE_UPPERCASE], [1], [Boolean values of ${FOUND__BOOL_TYPE} are defined as upper-case tokens])])
+                    AS_IF([${HAVE__BOOL_VALUE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_VALUE_CAMELCASE], [1], [Boolean values of ${FOUND__BOOL_TYPE} are defined as camel-case tokens])])
+
+                    AS_IF([${HAVE__BOOL_IMPLEM_INT}],   [AC_DEFINE_UNQUOTED([HAVE__BOOL_IMPLEM_INT],   [1], [Boolean type ${FOUND__BOOL_TYPE} is defined as a general-purpose number type (int)])])
+                    AS_IF([${HAVE__BOOL_IMPLEM_ENUM}],  [AC_DEFINE_UNQUOTED([HAVE__BOOL_IMPLEM_ENUM],  [1], [Boolean type ${FOUND__BOOL_TYPE} is defined as an enum with specific values allowed])])
+                    AS_IF([${HAVE__BOOL_IMPLEM_MACRO}], [AC_DEFINE_UNQUOTED([HAVE__BOOL_IMPLEM_MACRO], [1], [Boolean values of ${FOUND__BOOL_TYPE} are defined as a preprocessor macro (type/implem is questionable)])])
+            ],
+            [AC_MSG_NOTICE([Detected a "_Bool"-like type name ${FOUND__BOOL_TYPE}, but it was not semantically usable])])
+    ], [AC_MSG_NOTICE([A "_Bool"-like type name or its useful values were not detected])])
+
+    dnl ####################################################################
+
+    AS_IF([test x"${FOUND_BOOL_TYPE}" != x && test x"${FOUND_BOOL_VALUE_TRUE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+#ifndef ${FOUND_BOOL_VALUE_TRUE}
+#error "${FOUND_BOOL_VALUE_TRUE} is not a macro
+#endif
+#ifndef ${FOUND_BOOL_VALUE_FALSE}
+#error "${FOUND_BOOL_VALUE_FALSE} is not a macro
+#endif
+    ])], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND_BOOL_TYPE} bT = ${FOUND_BOOL_VALUE_TRUE};
+bT = 42
+    ])], [HAVE_BOOL_IMPLEM_INT=true; FOUND_BOOL_IMPLEM="number"], [HAVE_BOOL_IMPLEM_ENUM=true; FOUND_BOOL_IMPLEM="enum"])
+    ], [HAVE_BOOL_IMPLEM_MACRO=true; FOUND_BOOL_IMPLEM="macro"])
+
+            dnl # Final check
+            AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND_BOOL_TYPE} b = ${FOUND_BOOL_VALUE_TRUE};
+int ret = 0;
+
+if (!(!b == ${FOUND_BOOL_VALUE_FALSE})) ret = 1;
+if (!(b  != ${FOUND_BOOL_VALUE_FALSE})) ret = 2;
+if (!(!b != ${FOUND_BOOL_VALUE_TRUE}))  ret = 3;
+if (!b) ret = 4;
+if (ret)
+    return ret
+/* no ";return 0;" here - autoconf adds one */
+            ])],
+            [ dnl # All tests passed, remember this
+                    AC_MSG_NOTICE([Detected a semantically usable "bool"-like type name ${FOUND_BOOL_TYPE} implemented as ${FOUND_BOOL_IMPLEM} with boolean values '${FOUND_BOOL_VALUE_TRUE}' and '${FOUND_BOOL_VALUE_FALSE}'])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_TYPE],        [${FOUND_BOOL_TYPE}], [C spelling of bool type])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_IMPLEM_STR],  ["${FOUND_BOOL_IMPLEM}"], [String spelling of bool type implementation])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_VALUE_TRUE],  [${FOUND_BOOL_VALUE_TRUE}], [C spelling of bool type true value])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_VALUE_FALSE], [${FOUND_BOOL_VALUE_FALSE}], [C spelling of bool type false value])
+
+                    AS_IF([${HAVE_BOOL_TYPE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_TYPE_LOWERCASE], [1], [Name of ${FOUND_BOOL_TYPE} is defined as lower-case token])])
+                    AS_IF([${HAVE_BOOL_TYPE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_TYPE_UPPERCASE], [1], [Name of ${FOUND_BOOL_TYPE} is defined as upper-case token])])
+                    AS_IF([${HAVE_BOOL_TYPE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_TYPE_CAMELCASE], [1], [Name of ${FOUND_BOOL_TYPE} is defined as camel-case token])])
+
+                    AS_IF([${HAVE_BOOL_VALUE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_VALUE_LOWERCASE], [1], [Boolean values of ${FOUND_BOOL_TYPE} are defined as lower-case tokens])])
+                    AS_IF([${HAVE_BOOL_VALUE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_VALUE_UPPERCASE], [1], [Boolean values of ${FOUND_BOOL_TYPE} are defined as upper-case tokens])])
+                    AS_IF([${HAVE_BOOL_VALUE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_VALUE_CAMELCASE], [1], [Boolean values of ${FOUND_BOOL_TYPE} are defined as camel-case tokens])])
+
+                    AS_IF([${HAVE_BOOL_IMPLEM_INT}],   [AC_DEFINE_UNQUOTED([HAVE_BOOL_IMPLEM_INT],   [1], [Boolean type ${FOUND_BOOL_TYPE} is defined as a general-purpose number type (int)])])
+                    AS_IF([${HAVE_BOOL_IMPLEM_ENUM}],  [AC_DEFINE_UNQUOTED([HAVE_BOOL_IMPLEM_ENUM],  [1], [Boolean type ${FOUND_BOOL_TYPE} is defined as an enum with specific values allowed])])
+                    AS_IF([${HAVE_BOOL_IMPLEM_MACRO}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_IMPLEM_MACRO], [1], [Boolean values of ${FOUND_BOOL_TYPE} are defined as a preprocessor macro (type/implem is questionable)])])
+            ],
+            [AC_MSG_NOTICE([Detected a "bool"-like type name ${FOUND_BOOL_TYPE}, but it was not semantically usable])])
+    ], [AC_MSG_NOTICE([A "bool"-like type name or its useful values were not detected])])
+
+    dnl ####################################################################
+
+    AS_IF([test x"${FOUND_BOOLEAN_TYPE}" != x && test x"${FOUND_BOOLEAN_VALUE_TRUE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+#ifndef ${FOUND_BOOLEAN_VALUE_TRUE}
+#error "${FOUND_BOOLEAN_VALUE_TRUE} is not a macro
+#endif
+#ifndef ${FOUND_BOOLEAN_VALUE_FALSE}
+#error "${FOUND_BOOLEAN_VALUE_FALSE} is not a macro
+#endif
+    ])], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND_BOOLEAN_TYPE} bT = ${FOUND_BOOLEAN_VALUE_TRUE};
+bT = 42
+    ])], [HAVE_BOOLEAN_IMPLEM_INT=true; FOUND_BOOLEAN_IMPLEM="number"], [HAVE_BOOLEAN_IMPLEM_ENUM=true; FOUND_BOOLEAN_IMPLEM="enum"])
+    ], [HAVE_BOOLEAN_IMPLEM_MACRO=true; FOUND_BOOLEAN_IMPLEM="macro"])
+
+            dnl # Final check
+            AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND_BOOLEAN_TYPE} b = ${FOUND_BOOLEAN_VALUE_TRUE};
+int ret = 0;
+
+if (!(!b == ${FOUND_BOOLEAN_VALUE_FALSE})) ret = 1;
+if (!(b  != ${FOUND_BOOLEAN_VALUE_FALSE})) ret = 2;
+if (!(!b != ${FOUND_BOOLEAN_VALUE_TRUE}))  ret = 3;
+if (!b) ret = 4;
+if (ret)
+    return ret
+/* no ";return 0;" here - autoconf adds one */
+            ])],
+            [ dnl # All tests passed, remember this
+                    AC_MSG_NOTICE([Detected a semantically usable "boolean"-like type name ${FOUND_BOOLEAN_TYPE} implemented as ${FOUND_BOOLEAN_IMPLEM} with boolean values '${FOUND_BOOLEAN_VALUE_TRUE}' and '${FOUND_BOOL_VALUE_FALSE}'])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOLEAN_TYPE],        [${FOUND_BOOLEAN_TYPE}], [C spelling of boolean type])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOLEAN_IMPLEM_STR],  ["${FOUND_BOOLEAN_IMPLEM}"], [String spelling of boolean type implementation])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOLEAN_VALUE_TRUE],  [${FOUND_BOOLEAN_VALUE_TRUE}], [C spelling of boolean type true value])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOLEAN_VALUE_FALSE], [${FOUND_BOOLEAN_VALUE_FALSE}], [C spelling of boolean type false value])
+
+                    AS_IF([${HAVE_BOOLEAN_TYPE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_TYPE_LOWERCASE], [1], [Name of ${FOUND_BOOLEAN_TYPE} is defined as lower-case token])])
+                    AS_IF([${HAVE_BOOLEAN_TYPE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_TYPE_UPPERCASE], [1], [Name of ${FOUND_BOOLEAN_TYPE} is defined as upper-case token])])
+                    AS_IF([${HAVE_BOOLEAN_TYPE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_TYPE_CAMELCASE], [1], [Name of ${FOUND_BOOLEAN_TYPE} is defined as camel-case token])])
+
+                    AS_IF([${HAVE_BOOLEAN_VALUE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_VALUE_LOWERCASE], [1], [Boolean values of ${FOUND_BOOLEAN_TYPE} are defined as lower-case tokens])])
+                    AS_IF([${HAVE_BOOLEAN_VALUE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_VALUE_UPPERCASE], [1], [Boolean values of ${FOUND_BOOLEAN_TYPE} are defined as upper-case tokens])])
+                    AS_IF([${HAVE_BOOLEAN_VALUE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_VALUE_CAMELCASE], [1], [Boolean values of ${FOUND_BOOLEAN_TYPE} are defined as camel-case tokens])])
+
+                    AS_IF([${HAVE_BOOLEAN_IMPLEM_INT}],   [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_IMPLEM_INT],   [1], [Boolean type ${FOUND_BOOLEAN_TYPE} is defined as a general-purpose number type (int)])])
+                    AS_IF([${HAVE_BOOLEAN_IMPLEM_ENUM}],  [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_IMPLEM_ENUM],  [1], [Boolean type ${FOUND_BOOLEAN_TYPE} is defined as an enum with specific values allowed])])
+                    AS_IF([${HAVE_BOOLEAN_IMPLEM_MACRO}], [AC_DEFINE_UNQUOTED([HAVE_BOOLEAN_IMPLEM_MACRO], [1], [Boolean values of ${FOUND_BOOLEAN_TYPE} are defined as a preprocessor macro (type/implem is questionable)])])
+            ],
+            [AC_MSG_NOTICE([Detected a "boolean"-like type name ${FOUND_BOOLEAN_TYPE}, but it was not semantically usable])])
+    ], [AC_MSG_NOTICE([A "boolean"-like type name or its useful values were not detected])])
+
+    dnl ####################################################################
+
+    AS_IF([test x"${FOUND_BOOL_T_TYPE}" != x && test x"${FOUND_BOOL_T_VALUE_TRUE}" != x], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+#ifndef ${FOUND_BOOL_T_VALUE_TRUE}
+#error "${FOUND_BOOL_T_VALUE_TRUE} is not a macro
+#endif
+    ])], [
+            AC_COMPILE_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_T_STDBOOL}], [
+${FOUND_BOOL_T_TYPE} bT = ${FOUND_BOOL_T_VALUE_TRUE};
+bT = 42
+    ])], [HAVE_BOOL_T_IMPLEM_INT=true; FOUND_BOOL_T_IMPLEM="number"], [HAVE_BOOL_T_IMPLEM_ENUM=true; FOUND_BOOL_T_IMPLEM="enum"])
+    ], [HAVE_BOOL_T_IMPLEM_MACRO=true; FOUND_BOOL_T_IMPLEM="macro"])
+
+            dnl # Final check
+            AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([${myINCLUDE_STDBOOL}], [
+${FOUND_BOOL_T_TYPE} b = ${FOUND_BOOL_T_VALUE_TRUE};
+int ret = 0;
+
+if (!(!b == ${FOUND_BOOL_T_VALUE_FALSE})) ret = 1;
+if (!(b  != ${FOUND_BOOL_T_VALUE_FALSE})) ret = 2;
+if (!(!b != ${FOUND_BOOL_T_VALUE_TRUE}))  ret = 3;
+if (!b) ret = 4;
+if (ret)
+    return ret
+/* no ";return 0;" here - autoconf adds one */
+            ])],
+            [ dnl # All tests passed, remember this
+                    AC_MSG_NOTICE([Detected a semantically usable "bool_t"-like type name ${FOUND_BOOL_T_TYPE} implemented as ${FOUND_BOOL_T_IMPLEM} with boolean values '${FOUND_BOOL_T_VALUE_TRUE}' and '${FOUND_BOOL_T_VALUE_FALSE}'])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_T_TYPE],        [${FOUND_BOOL_T_TYPE}], [C spelling of bool_t type])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_T_IMPLEM_STR],  ["${FOUND_BOOL_T_IMPLEM}"], [String spelling of bool_t type implementation])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_T_VALUE_TRUE],  [${FOUND_BOOL_T_VALUE_TRUE}], [C spelling of bool_t type true value])
+                    AC_DEFINE_UNQUOTED([FOUND_BOOL_T_VALUE_FALSE], [${FOUND_BOOL_T_VALUE_FALSE}], [C spelling of bool_t type false value])
+
+                    AS_IF([${HAVE_BOOL_T_TYPE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_TYPE_LOWERCASE], [1], [Name of ${FOUND_BOOL_T_TYPE} is defined as lower-case token])])
+                    AS_IF([${HAVE_BOOL_T_TYPE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_TYPE_UPPERCASE], [1], [Name of ${FOUND_BOOL_T_TYPE} is defined as upper-case token])])
+                    AS_IF([${HAVE_BOOL_T_TYPE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_TYPE_CAMELCASE], [1], [Name of ${FOUND_BOOL_T_TYPE} is defined as camel-case token])])
+
+                    AS_IF([${HAVE_BOOL_T_VALUE_LOWERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_VALUE_LOWERCASE], [1], [Boolean values of ${FOUND_BOOL_T_TYPE} are defined as lower-case tokens])])
+                    AS_IF([${HAVE_BOOL_T_VALUE_UPPERCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_VALUE_UPPERCASE], [1], [Boolean values of ${FOUND_BOOL_T_TYPE} are defined as upper-case tokens])])
+                    AS_IF([${HAVE_BOOL_T_VALUE_CAMELCASE}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_VALUE_CAMELCASE], [1], [Boolean values of ${FOUND_BOOL_T_TYPE} are defined as camel-case tokens])])
+
+                    AS_IF([${HAVE_BOOL_T_IMPLEM_INT}],   [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_IMPLEM_INT],   [1], [Boolean type ${FOUND_BOOL_T_TYPE} is defined as a general-purpose number type (int)])])
+                    AS_IF([${HAVE_BOOL_T_IMPLEM_ENUM}],  [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_IMPLEM_ENUM],  [1], [Boolean type ${FOUND_BOOL_T_TYPE} is defined as an enum with specific values allowed])])
+                    AS_IF([${HAVE_BOOL_T_IMPLEM_MACRO}], [AC_DEFINE_UNQUOTED([HAVE_BOOL_T_IMPLEM_MACRO], [1], [Boolean values of ${FOUND_BOOL_T_TYPE} are defined as a preprocessor macro (type/implem is questionable)])])
+            ],
+            [AC_MSG_NOTICE([Detected a "bool_t"-like type name ${FOUND_BOOL_T_TYPE}, but it was not semantically usable])])
+    ], [AC_MSG_NOTICE([A "bool_t"-like type name or its useful values were not detected])])
+
+    dnl ####################################################################
+
+    AC_LANG_POP([C])
+
+fi
+])
diff --git a/m4/nut_check_headers_windows.m4 b/m4/nut_check_headers_windows.m4
index ce0286d045..4d52a15961 100644
--- a/m4/nut_check_headers_windows.m4
+++ b/m4/nut_check_headers_windows.m4
@@ -208,3 +208,41 @@ AC_DEFUN([NUT_CHECK_HEADER_WS2TCPIP], [
   esac
   AM_CONDITIONAL(HAVE_WS2TCPIP_H, test "x$nut_cv_header_ws2tcpip_h" = xyes)
 ])
+
+dnl NUT_CHECK_HEADER_IPHLPAPI
+dnl -------------------------------------------------
+dnl Check for compilable and valid iphlpapi.h header
+
+AC_DEFUN([NUT_CHECK_HEADER_IPHLPAPI], [
+  AC_REQUIRE([NUT_CHECK_HEADER_WINSOCK2])dnl
+  AC_CACHE_CHECK([for iphlpapi.h], [nut_cv_header_iphlpapi_h], [
+    AC_LANG_PUSH([C])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([[
+#undef inline
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#endif
+#include <windows.h>
+#include <winsock2.h>
+#include <iphlpapi.h>
+      ]],[[
+        PIP_ADAPTER_ADDRESSES pAddresses = NULL;
+        IP_ADAPTER_PREFIX *pPrefix = NULL;
+        PIP_ADAPTER_INFO pAdapter = NULL;
+      ]])
+    ],[
+      nut_cv_header_iphlpapi_h="yes"
+    ],[
+      nut_cv_header_iphlpapi_h="no"
+    ])
+    AC_LANG_POP([C])
+  ])
+  AS_CASE([$nut_cv_header_iphlpapi_h],
+    [yes], [
+      AC_DEFINE_UNQUOTED(HAVE_IPHLPAPI_H, 1,
+        [Define to 1 if you have the iphlpapi.h header file.])
+      ]
+  )
+  AM_CONDITIONAL(HAVE_IPHLPAPI_H, test "x$nut_cv_header_iphlpapi_h" = xyes)
+])
diff --git a/m4/nut_check_libavahi.m4 b/m4/nut_check_libavahi.m4
index d0c4989d61..feddcce281 100644
--- a/m4/nut_check_libavahi.m4
+++ b/m4/nut_check_libavahi.m4
@@ -83,6 +83,22 @@ if test -z "${nut_have_avahi_seen}"; then
 			LIBAVAHI_CFLAGS="${CFLAGS}"
 			LIBAVAHI_LIBS="${LIBS}"
 		fi
+
+		dnl Help ltdl if we can (nut-scanner etc.)
+		for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*avahi*client*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBAVAHI], [])
+					AS_IF([test -n "${SOPATH_LIBAVAHI}" && test -s "${SOPATH_LIBAVAHI}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBAVAHI],["${SOPATH_LIBAVAHI}"],[Path to dynamic library on build system])
+						SOFILE_LIBAVAHI="`basename "$SOPATH_LIBAVAHI"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBAVAHI],["${SOFILE_LIBAVAHI}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		done
+		unset TOKEN
 	fi
 
 	dnl restore original CFLAGS and LIBS
diff --git a/m4/nut_check_libfreeipmi.m4 b/m4/nut_check_libfreeipmi.m4
index 5fad0c6438..45190ea45f 100644
--- a/m4/nut_check_libfreeipmi.m4
+++ b/m4/nut_check_libfreeipmi.m4
@@ -92,6 +92,22 @@ if test -z "${nut_have_libfreeipmi_seen}"; then
 		AC_DEFINE(HAVE_FREEIPMI, 1, [Define if FreeIPMI support is available])
 		LIBIPMI_CFLAGS="${CFLAGS}"
 		LIBIPMI_LIBS="${LIBS}"
+
+		dnl Help ltdl if we can (nut-scanner etc.)
+		for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*ipmi*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBFREEIPMI], [])
+					AS_IF([test -n "${SOPATH_LIBFREEIPMI}" && test -s "${SOPATH_LIBFREEIPMI}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBFREEIPMI],["${SOPATH_LIBFREEIPMI}"],[Path to dynamic library on build system])
+						SOFILE_LIBFREEIPMI="`basename "$SOPATH_LIBFREEIPMI"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBFREEIPMI],["${SOFILE_LIBFREEIPMI}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		done
+		unset TOKEN
 	fi
 
 	if test "${nut_have_freeipmi_11x_12x}" = "yes"; then
diff --git a/m4/nut_check_libgd.m4 b/m4/nut_check_libgd.m4
index a8c7de5d17..b2b56666aa 100644
--- a/m4/nut_check_libgd.m4
+++ b/m4/nut_check_libgd.m4
@@ -141,6 +141,28 @@ if test -z "${nut_have_libgd_seen}"; then
 		])
 	])
 
+	if test "${nut_have_libgd}" = "yes"; then
+		AC_MSG_CHECKING([whether we can build, link and/or run a program with libgd])
+		AC_LANG_PUSH([C])
+		AX_RUN_OR_LINK_IFELSE([AC_LANG_PROGRAM([
+#include <gd.h>
+#include <gdfontmb.h>
+#include <stdio.h>
+],
+[
+FILE *tmpf = tmpfile();
+gdImagePtr im = gdImageCreate(64, 128);
+int back_color = gdImageColorAllocate(im, 255, 128, 32);
+gdImageFilledRectangle(im, 0, 0, 64, 128, back_color);
+gdImageColorTransparent(im, back_color);
+gdImagePng(im, tmpf ? tmpf : stderr);
+gdImageDestroy(im);
+]
+		)], [], [nut_have_libgd=no])
+		AC_LANG_POP([C])
+		AC_MSG_RESULT([${nut_have_libgd}])
+	fi
+
 	if test "${nut_have_libgd}" = "yes"; then
 		AC_DEFINE(HAVE_LIBGD, 1, [Define if you have Boutell's libgd installed])
 		LIBGD_CFLAGS="${CFLAGS}"
diff --git a/m4/nut_check_libltdl.m4 b/m4/nut_check_libltdl.m4
index 8c6857ecfe..9c67e93eef 100644
--- a/m4/nut_check_libltdl.m4
+++ b/m4/nut_check_libltdl.m4
@@ -50,12 +50,19 @@ if test -z "${nut_have_libltdl_seen}"; then
 	], [])dnl No fallback here - we probe suitable libs below
 	AC_MSG_RESULT([${LIBS}])
 
-	AC_CHECK_HEADERS(ltdl.h, [nut_have_libltdl=yes], [nut_have_libltdl=no], [AC_INCLUDES_DEFAULT])
+	AC_CHECK_HEADERS(ltdl.h, [nut_have_libltdl=yes], [
+		dnl Double-check if we stashed include paths to try above
+		AS_IF([test -n "$myCFLAGS"], [
+			CFLAGS="$myCFLAGS"
+			AS_UNSET([ac_cv_header_ltdl_h])
+			AC_CHECK_HEADERS(ltdl.h, [nut_have_libltdl=yes], [nut_have_libltdl=no], [AC_INCLUDES_DEFAULT])
+			],[nut_have_libltdl=no]
+		)], [AC_INCLUDES_DEFAULT])
 	AS_IF([test x"$nut_have_libltdl" = xyes], [
 		dnl ltdl-number may help find it for MingW DLLs naming
 		AC_SEARCH_LIBS(lt_dlinit, ltdl ltdl-7, [], [
 			nut_have_libltdl=no
-			AS_IF([test -n "$myCFLAGS"], [
+			AS_IF([test -n "$myCFLAGS" -a x"$myCFLAGS" != x"$CFLAGS"], [
 				CFLAGS="$myCFLAGS"
 				dnl No ltdl-7 here, this codepath is unlikely on Windows where that matters:
 				AC_SEARCH_LIBS(lt_dlinit, ltdl, [nut_have_libltdl=yes], [])
diff --git a/m4/nut_check_libmodbus.m4 b/m4/nut_check_libmodbus.m4
index dbaae4968e..c596bb1edc 100644
--- a/m4/nut_check_libmodbus.m4
+++ b/m4/nut_check_libmodbus.m4
@@ -72,7 +72,12 @@ if test -z "${nut_have_libmodbus_seen}"; then
 	AC_CHECK_FUNCS(modbus_set_byte_timeout, [], [nut_have_libmodbus=no])
 	AC_CHECK_FUNCS(modbus_set_response_timeout, [], [nut_have_libmodbus=no])
 
-	AC_CHECK_FUNCS(modbus_new_rtu_usb, [nut_have_libmodbus_usb=yes], [nut_have_libmodbus_usb=no])
+	AC_CHECK_FUNCS(modbus_new_rtu_usb, [nut_have_libmodbus_usb=yes], [
+		AS_IF([test x"${nut_with_usb}" = xyes && test x"${nut_with_modbus}" = xyes && test x"${nut_have_libmodbus}" = xyes ], [
+			AC_MSG_WARN([Both --with-modbus and --with-usb were requested, and a libmodbus was found, but it seems to not support USB. You may require a custom build per https://github.com/networkupstools/nut/wiki/APC-UPS-with-Modbus-protocol])
+		])
+		nut_have_libmodbus_usb=no
+	])
 
 	dnl modbus_set_byte_timeout() and modbus_set_response_timeout()
 	dnl in 3.0.x and 3.1.x have different args (since ~2013): the
diff --git a/m4/nut_check_libneon.m4 b/m4/nut_check_libneon.m4
index 944f7a356e..015ed7dc71 100644
--- a/m4/nut_check_libneon.m4
+++ b/m4/nut_check_libneon.m4
@@ -78,6 +78,22 @@ if test -z "${nut_have_neon_seen}"; then
 		AC_CHECK_FUNCS(ne_set_connect_timeout ne_sock_connect_timeout)
 		LIBNEON_CFLAGS="${CFLAGS}"
 		LIBNEON_LIBS="${LIBS}"
+
+		dnl Help ltdl if we can (nut-scanner etc.)
+		for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*neon*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBNEON], [])
+					AS_IF([test -n "${SOPATH_LIBNEON}" && test -s "${SOPATH_LIBNEON}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBNEON],["${SOPATH_LIBNEON}"],[Path to dynamic library on build system])
+						SOFILE_LIBNEON="`basename "$SOPATH_LIBNEON"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBNEON],["${SOFILE_LIBNEON}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		done
+		unset TOKEN
 	fi
 
 	dnl restore original CFLAGS and LIBS
diff --git a/m4/nut_check_libnetsnmp.m4 b/m4/nut_check_libnetsnmp.m4
index 389ac2d2ff..ed341686d9 100644
--- a/m4/nut_check_libnetsnmp.m4
+++ b/m4/nut_check_libnetsnmp.m4
@@ -79,6 +79,7 @@ if test -z "${nut_have_libnetsnmp_seen}"; then
 		AC_MSG_WARN([did not find either net-snmp-config or pkg-config for net-snmp])
 	fi
 
+	myCFLAGS_SOURCE=""
 	AC_MSG_CHECKING(for Net-SNMP cflags)
 	AC_ARG_WITH(snmp-includes,
 		AS_HELP_STRING([@<:@--with-snmp-includes=CFLAGS@:>@], [include flags for the Net-SNMP library]),
@@ -88,17 +89,21 @@ if test -z "${nut_have_libnetsnmp_seen}"; then
 			AC_MSG_ERROR(invalid option --with(out)-snmp-includes - see docs/configure.txt)
 			;;
 		*)
+			myCFLAGS_SOURCE="confarg"
 			CFLAGS="${withval}"
 			;;
 		esac
 	], [AS_IF(["${prefer_NET_SNMP_CONFIG}"],
-		[CFLAGS="`${NET_SNMP_CONFIG} --base-cflags 2>/dev/null`"],
+		[CFLAGS="`${NET_SNMP_CONFIG} --base-cflags 2>/dev/null`"
+		 myCFLAGS_SOURCE="netsnmp-config"],
 		[AS_IF([test x"$have_PKG_CONFIG" = xyes],
-			[CFLAGS="`$PKG_CONFIG --silence-errors --cflags netsnmp 2>/dev/null`"]
+			[CFLAGS="`$PKG_CONFIG --silence-errors --cflags netsnmp 2>/dev/null`"
+			 myCFLAGS_SOURCE="pkg-config"],
+			[myCFLAGS_SOURCE="default"]
 			)]
 		)]
 	)
-	AC_MSG_RESULT([${CFLAGS}])
+	AC_MSG_RESULT([${CFLAGS} (source: ${myCFLAGS_SOURCE})])
 
 	myLIBS_SOURCE=""
 	AC_MSG_CHECKING(for Net-SNMP libs)
@@ -124,11 +129,19 @@ if test -z "${nut_have_libnetsnmp_seen}"; then
 			 myLIBS_SOURCE="default"])]
 		)]
 	)
-	AC_MSG_RESULT([${LIBS}])
+	AC_MSG_RESULT([${LIBS} (source: ${myLIBS_SOURCE})])
 
 	dnl Check if the Net-SNMP library is usable
 	nut_have_libnetsnmp_static=no
-	AC_CHECK_HEADERS(net-snmp/net-snmp-config.h, [nut_have_libnetsnmp=yes], [nut_have_libnetsnmp=no], [AC_INCLUDES_DEFAULT])
+	nut_have_libnetsnmp=no
+	AC_CHECK_HEADERS([net-snmp/net-snmp-config.h],
+		dnl The second header requires the first to be included
+		[AC_CHECK_HEADERS([net-snmp/net-snmp-includes.h], [nut_have_libnetsnmp=yes], [],
+		 [AC_INCLUDES_DEFAULT
+		 #include <net-snmp/net-snmp-config.h>
+		 ])
+		], [], [AC_INCLUDES_DEFAULT])
+
 	AC_CHECK_FUNCS(init_snmp, [], [
 		dnl Probably is dysfunctional, except one case...
 		nut_have_libnetsnmp=no
@@ -156,6 +169,7 @@ if test -z "${nut_have_libnetsnmp_seen}"; then
 		])
 	])
 	AS_UNSET([myLIBS_SOURCE])
+	AS_UNSET([myCFLAGS_SOURCE])
 
 	AS_IF([test "${nut_have_libnetsnmp}" = "yes"], [
 		LIBNETSNMP_CFLAGS="${CFLAGS}"
@@ -347,7 +361,23 @@ int num = NETSNMP_DRAFT_BLUMENTHAL_AES_04 + 1; /* if defined, NETSNMP_DRAFT_BLUM
 			 AC_DEFINE_UNQUOTED(NUT_HAVE_LIBNETSNMP_DRAFT_BLUMENTHAL_AES_04, 0, [Variable or macro by this name is not resolvable])
 			])
 
+		dnl Help ltdl if we can (nut-scanner etc.)
+		for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*snmp*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBNETSNMP], [])
+					AS_IF([test -n "${SOPATH_LIBNETSNMP}" && test -s "${SOPATH_LIBNETSNMP}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBNETSNMP],["${SOPATH_LIBNETSNMP}"],[Path to dynamic library on build system])
+						SOFILE_LIBNETSNMP="`basename "$SOPATH_LIBNETSNMP"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBNETSNMP],["${SOFILE_LIBNETSNMP}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		done
+		unset TOKEN
 	])
+
 	AC_LANG_POP([C])
 
 	dnl restore original CFLAGS and LIBS
diff --git a/m4/nut_check_libregex.m4 b/m4/nut_check_libregex.m4
index 86c2bc1552..8980b25d57 100644
--- a/m4/nut_check_libregex.m4
+++ b/m4/nut_check_libregex.m4
@@ -60,23 +60,19 @@ if test -z "${nut_have_libregex_seen}"; then
 	dnl # Maybe already involved in NUT for Windows builds...
 	nut_have_regex=no
 	AC_CHECK_HEADER([regex.h],
-		[nut_have_regex=yes
-		 AC_DEFINE([HAVE_REGEX_H], [1],
+		[AC_DEFINE([HAVE_REGEX_H], [1],
 			[Define to 1 if you have <regex.h>.])])
+
 	AC_CHECK_DECLS([regexec, regcomp], [nut_have_regex=yes], [],
 [#ifdef HAVE_REGEX_H
 # include <regex.h>
 #endif
 ])
 
-	AC_SEARCH_LIBS([regcomp, regexec], [], [nut_have_regex=yes], [
-		AS_IF([test x"$LIBS" = x], [
-			dnl Avoid using cached reply for the absent library name
-			unset ac_cv_search_regcomp__regexec || true
-			AC_SEARCH_LIBS([regcomp, regexec], [regex], [
-				LIBS="-lregex"
-				nut_have_regex=yes
-			])
+	AS_IF([test x"${nut_have_regex}" = xyes], [
+		nut_have_regex=no
+		AC_SEARCH_LIBS([regcomp], [regex], [
+			AC_SEARCH_LIBS([regcomp], [regex], [nut_have_regex=yes])
 		])
 	])
 
diff --git a/m4/nut_check_libsystemd.m4 b/m4/nut_check_libsystemd.m4
index 155add4423..cf7b09ccda 100644
--- a/m4/nut_check_libsystemd.m4
+++ b/m4/nut_check_libsystemd.m4
@@ -13,22 +13,42 @@ if test -z "${nut_have_libsystemd_seen}"; then
 	CFLAGS_ORIG="${CFLAGS}"
 	LIBS_ORIG="${LIBS}"
 
+	SYSTEMD_VERSION="none"
+
+	AC_CHECK_TOOL(SYSTEMCTL, systemctl, none)
+
 	AS_IF([test x"$have_PKG_CONFIG" = xyes],
 		[dnl See which version of the systemd library (if any) is installed
 		 dnl FIXME : Support detection of cflags/ldflags below by legacy
 		 dnl discovery if pkgconfig is not there
 		 AC_MSG_CHECKING(for libsystemd version via pkg-config)
 		 SYSTEMD_VERSION="`$PKG_CONFIG --silence-errors --modversion libsystemd 2>/dev/null`"
-		 if test "$?" != "0" -o -z "${SYSTEMD_VERSION}"; then
-		    SYSTEMD_VERSION="none"
-		 fi
+		 AS_IF([test "$?" != "0" -o -z "${SYSTEMD_VERSION}"], [
+			SYSTEMD_VERSION="none"
+		 ])
 		 AC_MSG_RESULT(${SYSTEMD_VERSION} found)
-		],
-		[SYSTEMD_VERSION="none"
-		 AC_MSG_NOTICE([can not check libsystemd settings via pkg-config])
 		]
 	)
 
+	AS_IF([test x"${SYSTEMD_VERSION}" = xnone], [
+		 AS_IF([test x"${SYSTEMCTL}" != xnone], [
+			AC_MSG_CHECKING(for libsystemd version via systemctl)
+			dnl NOTE: Unlike the configure.ac file, in a "pure"
+			dnl m4 script like this one, we have to escape the
+			dnl dollar-number references (in awk below) lest they
+			dnl get seen as m4 function positional parameters.
+			SYSTEMD_VERSION="`LANG=C LC_ALL=C ${SYSTEMCTL} --version | grep -E '^systemd@<:@ \t@:>@*@<:@0-9@:>@@<:@0-9@:>@*' | awk '{print ''$''2}'`" \
+			&& test -n "${SYSTEMD_VERSION}" \
+			|| SYSTEMD_VERSION="none"
+			AC_MSG_RESULT(${SYSTEMD_VERSION} found)
+		 ])
+		]
+	)
+
+	AS_IF([test x"${SYSTEMD_VERSION}" = xnone], [
+		AC_MSG_NOTICE([can not check libsystemd settings via pkg-config nor systemctl])
+	])
+
 	AC_MSG_CHECKING(for libsystemd cflags)
 	AC_ARG_WITH(libsystemd-includes,
 		AS_HELP_STRING([@<:@--with-libsystemd-includes=CFLAGS@:>@], [include flags for the systemd library]),
@@ -76,11 +96,31 @@ if test -z "${nut_have_libsystemd_seen}"; then
 	AC_CHECK_HEADERS(systemd/sd-daemon.h, [nut_have_libsystemd=yes], [nut_have_libsystemd=no], [AC_INCLUDES_DEFAULT])
 	AC_CHECK_FUNCS(sd_notify, [], [nut_have_libsystemd=no])
 
+	nut_have_libsystemd_inhibitor=no
 	AS_IF([test x"${nut_have_libsystemd}" = x"yes"], [
 		dnl Check for additional feature support in library (optional)
 		AC_CHECK_FUNCS(sd_booted sd_watchdog_enabled sd_notify_barrier)
 		LIBSYSTEMD_CFLAGS="${CFLAGS}"
 		LIBSYSTEMD_LIBS="${LIBS}"
+
+		dnl Since systemd 183: https://systemd.io/INHIBITOR_LOCKS/
+		dnl ...or 221: https://www.freedesktop.org/software/systemd/man/latest/sd_bus_call_method.html
+		dnl and some bits even later (e.g. message container reading)
+		AS_IF([test "$SYSTEMD_VERSION" -ge 221], [
+			nut_have_libsystemd_inhibitor=yes
+			AC_CHECK_HEADERS(systemd/sd-bus.h, [], [nut_have_libsystemd_inhibitor=no], [AC_INCLUDES_DEFAULT])
+			AC_CHECK_FUNCS([sd_bus_call_method sd_bus_message_read_basic sd_bus_open_system sd_bus_default_system sd_bus_get_property_trivial], [], [nut_have_libsystemd_inhibitor=no])
+			dnl NOTE: In practice we use "p"-suffixed sd_bus_flush_close_unrefp
+			dnl  and sd_bus_message_unrefp methods prepared by a macro in sd-bus.h
+			AC_CHECK_FUNCS([sd_bus_flush_close_unref sd_bus_message_unref sd_bus_error_free], [], [nut_have_libsystemd_inhibitor=no])
+			dnl Optional methods: nicer with them, can do without
+			AC_CHECK_FUNCS([sd_bus_open_system_with_description sd_bus_set_description])
+			dnl For inhibitor per se, we do not have to read containers:
+			dnl AC_CHECK_FUNCS([sd_bus_message_enter_container sd_bus_message_exit_container])
+		])
+
+		AC_MSG_CHECKING(for libsystemd inhibitor interface support)
+		AC_MSG_RESULT([${nut_have_libsystemd_inhibitor}])
 	])
 
 	dnl restore original CFLAGS and LIBS
diff --git a/m4/nut_check_libusb.m4 b/m4/nut_check_libusb.m4
index 186e7c6e2f..236e013355 100644
--- a/m4/nut_check_libusb.m4
+++ b/m4/nut_check_libusb.m4
@@ -88,9 +88,13 @@ if test -z "${nut_have_libusb_seen}"; then
 		 AS_IF([test x"${LIBUSB_0_1_VERSION}" != xnone], [
 			AS_CASE(["${target_os}"],
 				[*mingw*], [
-					AC_MSG_NOTICE([mingw builds prefer libusb-0.1(-compat) if available])
-					LIBUSB_VERSION="${LIBUSB_0_1_VERSION}"
-					nut_usb_lib="(libusb-0.1)"
+					AS_IF([test x"$build" = x"$host"], [
+						AC_MSG_NOTICE([mingw/MSYS2 native builds prefer libusb-0.1(-compat) over libusb-1.0 if both are available])
+						LIBUSB_VERSION="${LIBUSB_0_1_VERSION}"
+						nut_usb_lib="(libusb-0.1)"
+						],[
+						AC_MSG_NOTICE([mingw cross-builds prefer libusb-1.0 over libusb-0.1(-compat) if both are available])
+						])
 					])
 				]
 			)
@@ -371,14 +375,48 @@ if test -z "${nut_have_libusb_seen}"; then
 	dnl with some value.
 	AS_IF([test "${nut_with_usb}" = "yes" && test "${nut_usb_lib}" = "(libusb-1.0)"],
 		[AC_DEFINE([WITH_LIBUSB_1_0], [1],
-			[Define to 1 for version 1.0 of the libusb (via pkg-config).])],
+			[Define to 1 for version 1.0 of the libusb (via pkg-config).])
+
+		 dnl Help ltdl if we can (nut-scanner etc.)
+		 for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*usb*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBUSB1], [])
+					AS_IF([test -n "${SOPATH_LIBUSB1}" && test -s "${SOPATH_LIBUSB1}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBUSB1],["${SOPATH_LIBUSB1}"],[Path to dynamic library on build system])
+						SOFILE_LIBUSB1="`basename "$SOPATH_LIBUSB1"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBUSB1],["${SOFILE_LIBUSB1}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		 done
+		 unset TOKEN
+                ],
 		[AC_DEFINE([WITH_LIBUSB_1_0], [0],
 			[Define to 1 for version 1.0 of the libusb (via pkg-config).])]
 	)
 
 	AS_IF([test "${nut_with_usb}" = "yes" && test "${nut_usb_lib}" = "(libusb-0.1)" -o "${nut_usb_lib}" = "(libusb-0.1-config)"],
 		[AC_DEFINE([WITH_LIBUSB_0_1], [1],
-			[Define to 1 for version 0.1 of the libusb (via pkg-config or libusb-config).])],
+			[Define to 1 for version 0.1 of the libusb (via pkg-config or libusb-config).])
+
+		 dnl Help ltdl if we can (nut-scanner etc.)
+		 for TOKEN in $LIBS ; do
+			AS_CASE(["${TOKEN}"],
+				[-l*usb*], [
+					AX_REALPATH_LIB([${TOKEN}], [SOPATH_LIBUSB0], [])
+					AS_IF([test -n "${SOPATH_LIBUSB0}" && test -s "${SOPATH_LIBUSB0}"], [
+						AC_DEFINE_UNQUOTED([SOPATH_LIBUSB0],["${SOPATH_LIBUSB0}"],[Path to dynamic library on build system])
+						SOFILE_LIBUSB0="`basename "$SOPATH_LIBUSB0"`"
+						AC_DEFINE_UNQUOTED([SOFILE_LIBUSB0],["${SOFILE_LIBUSB0}"],[Base file name of dynamic library on build system])
+						break
+					])
+				]
+			)
+		 done
+		 unset TOKEN
+                ],
 		[AC_DEFINE([WITH_LIBUSB_0_1], [0],
 			[Define to 1 for version 0.1 of the libusb (via pkg-config or libusb-config).])]
 	)
diff --git a/m4/nut_check_pkgconfig.m4 b/m4/nut_check_pkgconfig.m4
index fd9a2449ef..4e2b6b77bd 100644
--- a/m4/nut_check_pkgconfig.m4
+++ b/m4/nut_check_pkgconfig.m4
@@ -5,7 +5,7 @@ dnl do the checking only once.
 
 AC_DEFUN([NUT_CHECK_PKGCONFIG],
 [
-AS_IF([test -z "${nut_have_pkg_config_seen}"], [
+  AS_IF([test -z "${nut_have_pkg_config_seen}"], [
 	nut_have_pkg_config_seen=yes
 
 	dnl Note that PKG_CONFIG may be a filename, path,
@@ -83,8 +83,43 @@ AS_IF([test -z "${nut_have_pkg_config_seen}"], [
 		 PKG_CONFIG="false"
 		],
 		[AS_IF([test x"$have_PKG_CONFIG_MACROS" = xno],
-			[AC_MSG_WARN([pkg-config macros are needed to look for further dependencies, but in some cases pkg-config program can be used directly])]
-		)]
+			[AC_MSG_WARN([pkg-config macros are needed to look for further dependencies, but in some cases pkg-config program can be used directly])])
+
+		 AC_MSG_CHECKING([for pkg-config envvar PKG_CONFIG_PATH (if passed to configure script)])
+		 AC_MSG_RESULT([${PKG_CONFIG_PATH}])
+
+		 AC_MSG_CHECKING([for pkg-config reported pc_path])
+		 myPKG_CONFIG_PC_PATH="`pkg-config --variable pc_path pkg-config`" || myPKG_CONFIG_PC_PATH=""
+		 AC_MSG_RESULT([${myPKG_CONFIG_PC_PATH}])
+
+		 dnl # The piece below is inspired by https://github.com/wxWidgets/wxWidgets/commit/7899850496ba2707c41cc534b51d14ac5b9fdbba
+		 dnl When cross-compiling for another system from Linux, don't use .pc files on
+		 dnl the build system, they are at best useless and can be harmful (e.g. they
+		 dnl may define options inappropriate for the cross-build, resulting in the
+		 dnl failure of all the subsequent tests).
+		 dnl
+		 dnl However do use .pc files for the host libraries that can be found by the
+		 dnl host-specific pkg-config if it was found by PKG_PROG_PKG_CONFIG above.
+		 AS_IF([test x"$build" != x"$host"], [
+			AS_CASE(["$PKG_CONFIG"],
+				[*/"$host"-pkg-config], [],
+				[AC_MSG_WARN([Not using native pkg-config when cross-compiling.])
+
+				 dnl pkg.m4 forbids the use of PKG_XXX, so undo it here
+				 dnl to avoid autoconf errors.
+				 m4_pattern_allow([PKG_CONFIG_LIBDIR])
+
+				 dnl If pkg-config libdir is already defined, we suppose that
+				 dnl callers know what they're doing and leave it alone, but
+				 dnl if not, set it to a path in which no .pc files will be found.
+				 AS_IF([test x"$PKG_CONFIG_LIBDIR" = x], [
+					AC_MSG_WARN([Exporting a hack PKG_CONFIG_LIBDIR to avoid search for .pc files in host paths])
+					PKG_CONFIG_LIBDIR=/dev/null
+					export PKG_CONFIG_LIBDIR
+					])
+				])
+			])
+		]
 	)
 
   ]) dnl if nut_have_pkg_config_seen
diff --git a/m4/nut_check_python.m4 b/m4/nut_check_python.m4
index b44a5cd5bb..b05057d8eb 100644
--- a/m4/nut_check_python.m4
+++ b/m4/nut_check_python.m4
@@ -47,6 +47,8 @@ AC_DEFUN([NUT_CHECK_PYTHON],
         PYTHON=""
         PYTHON_SITE_PACKAGES=""
         PYTHON_VERSION_REPORT=""
+        PYTHON_VERSION_INFO_REPORT=""
+        PYTHON_SYSPATH_REPORT=""
         AS_CASE([${nut_with_python}],
             [auto|yes|""], [AC_CHECK_PROGS([PYTHON], [python python3 python2], [_python_runtime])],
             [no], [PYTHON="no"],
@@ -98,7 +100,7 @@ AC_DEFUN([NUT_CHECK_PYTHON],
 
         AS_IF([test -n "${PYTHON}" && test "${PYTHON}" != "no"], [
             AS_IF([test x"`$PYTHON -c 'import sys; print (sys.version_info >= (2, 6))'`" = xTrue],
-                [PYTHON_VERSION_REPORT=" (`$PYTHON -c 'import sys; print (sys.version_info)'`)"],
+                [PYTHON_VERSION_INFO_REPORT=" (`$PYTHON -c 'import sys; print (sys.version_info)'`)"],
                 [AC_MSG_WARN([Version reported by ${PYTHON} was not suitable as python])
                  PYTHON=no])
             ])
@@ -111,10 +113,21 @@ AC_DEFUN([NUT_CHECK_PYTHON],
             ])
 
         AC_MSG_CHECKING([python interpeter to call])
-        AC_MSG_RESULT([${PYTHON}${PYTHON_VERSION_REPORT}])
+        AC_MSG_RESULT([${PYTHON}${PYTHON_VERSION_INFO_REPORT}])
         AC_SUBST([PYTHON], [${PYTHON}])
         AM_CONDITIONAL([HAVE_PYTHON], [test -n "${PYTHON}" && test "${PYTHON}" != "no"])
         AS_IF([test -n "${PYTHON}" && test "${PYTHON}" != "no"], [
+            AC_MSG_CHECKING([python build sys.version])
+            dnl Can have extra lines about compiler used, etc.
+            PYTHON_VERSION_REPORT="`${PYTHON} -c 'import sys; print(sys.version);' | tr '\n' ' '`" \
+            || PYTHON_VERSION_REPORT=""
+            AC_MSG_RESULT([${PYTHON_VERSION_REPORT}])
+
+            AC_MSG_CHECKING([python sys.path used to search for modules])
+            PYTHON_SYSPATH_REPORT="`${PYTHON} -c 'import sys; print(sys.path);'`" \
+            || PYTHON_SYSPATH_REPORT=""
+            AC_MSG_RESULT([${PYTHON_SYSPATH_REPORT}])
+
             export PYTHON
             AC_CACHE_CHECK([python site-packages location], [nut_cv_PYTHON_SITE_PACKAGES], [
                 nut_cv_PYTHON_SITE_PACKAGES="`${PYTHON} -c 'import site; print(site.getsitepackages().pop(0))'`"
@@ -139,10 +152,12 @@ AC_DEFUN([NUT_CHECK_PYTHON2],
         PYTHON2=""
         PYTHON2_SITE_PACKAGES=""
         PYTHON2_VERSION_REPORT=""
+        PYTHON2_VERSION_INFO_REPORT=""
+        PYTHON2_SYSPATH_REPORT=""
         AS_CASE([${nut_with_python2}],
             [auto|yes|""], [
                 dnl Cross check --with-python results:
-                AS_CASE(["${PYTHON_VERSION_REPORT}"],
+                AS_CASE(["${PYTHON_VERSION_INFO_REPORT}"],
                     [*major=2,*], [
                         PYTHON2="`${PYTHON} -c 'import sys; print(sys.executable);' 2>/dev/null`" && test -n "${PYTHON2}" || PYTHON2="${PYTHON}"
                         PYTHON2="`realpath "${PYTHON2}" 2>/dev/null`" && test -n "${PYTHON2}" || {
@@ -210,7 +225,7 @@ AC_DEFUN([NUT_CHECK_PYTHON2],
 
         AS_IF([test -n "${PYTHON2}" && test "${PYTHON2}" != "no"], [
             AS_IF([test x"`$PYTHON2 -c 'import sys; print (sys.version_info >= (2, 6) and sys.version_info < (3, 0))'`" = xTrue],
-                [PYTHON2_VERSION_REPORT=" (`$PYTHON2 -c 'import sys; print (sys.version_info)'`)"],
+                [PYTHON2_VERSION_INFO_REPORT=" (`$PYTHON2 -c 'import sys; print (sys.version_info)'`)"],
                 [AC_MSG_WARN([Version reported by ${PYTHON2} was not suitable as python2])
                  PYTHON2=no])
             ])
@@ -223,10 +238,21 @@ AC_DEFUN([NUT_CHECK_PYTHON2],
             ])
 
         AC_MSG_CHECKING([python2 interpeter to call])
-        AC_MSG_RESULT([${PYTHON2}${PYTHON2_VERSION_REPORT}])
+        AC_MSG_RESULT([${PYTHON2}${PYTHON2_VERSION_INFO_REPORT}])
         AC_SUBST([PYTHON2], [${PYTHON2}])
         AM_CONDITIONAL([HAVE_PYTHON2], [test -n "${PYTHON2}" && test "${PYTHON2}" != "no"])
         AS_IF([test -n "${PYTHON2}" && test "${PYTHON2}" != "no"], [
+            AC_MSG_CHECKING([python2 build sys.version])
+            dnl Can have extra lines about compiler used, etc.
+            PYTHON2_VERSION_REPORT="`${PYTHON2} -c 'import sys; print(sys.version);' | tr '\n' ' '`" \
+            || PYTHON2_VERSION_REPORT=""
+            AC_MSG_RESULT([${PYTHON2_VERSION_REPORT}])
+
+            AC_MSG_CHECKING([python2 sys.path used to search for modules])
+            PYTHON2_SYSPATH_REPORT="`${PYTHON2} -c 'import sys; print(sys.path);'`" \
+            || PYTHON2_SYSPATH_REPORT=""
+            AC_MSG_RESULT([${PYTHON2_SYSPATH_REPORT}])
+
             export PYTHON2
             AC_CACHE_CHECK([python2 site-packages location], [nut_cv_PYTHON2_SITE_PACKAGES], [
                 nut_cv_PYTHON2_SITE_PACKAGES="`${PYTHON2} -c 'import site; print(site.getsitepackages().pop(0))'`"
@@ -251,10 +277,12 @@ AC_DEFUN([NUT_CHECK_PYTHON3],
         PYTHON3=""
         PYTHON3_SITE_PACKAGES=""
         PYTHON3_VERSION_REPORT=""
+        PYTHON3_VERSION_INFO_REPORT=""
+        PYTHON3_SYSPATH_REPORT=""
         AS_CASE([${nut_with_python3}],
             [auto|yes|""], [
                 dnl Cross check --with-python results:
-                AS_CASE(["${PYTHON_VERSION_REPORT}"],
+                AS_CASE(["${PYTHON_VERSION_INFO_REPORT}"],
                     [*major=3,*], [
                         PYTHON3="`${PYTHON} -c 'import sys; print(sys.executable);' 2>/dev/null`" && test -n "${PYTHON3}" || PYTHON3="${PYTHON}"
                         PYTHON3="`realpath "${PYTHON3}" 2>/dev/null`" && test -n "${PYTHON3}" || {
@@ -322,7 +350,7 @@ AC_DEFUN([NUT_CHECK_PYTHON3],
 
         AS_IF([test -n "${PYTHON3}" && test "${PYTHON3}" != "no"], [
             AS_IF([test x"`$PYTHON3 -c 'import sys; print (sys.version_info >= (3, 0))'`" = xTrue],
-                [PYTHON3_VERSION_REPORT=" (`$PYTHON3 -c 'import sys; print (sys.version_info)'`)"],
+                [PYTHON3_VERSION_INFO_REPORT=" (`$PYTHON3 -c 'import sys; print (sys.version_info)'`)"],
                 [AC_MSG_WARN([Version reported by ${PYTHON3} was not suitable as python3])
                  PYTHON3=no])
             ])
@@ -335,10 +363,21 @@ AC_DEFUN([NUT_CHECK_PYTHON3],
             ])
 
         AC_MSG_CHECKING([python3 interpeter to call])
-        AC_MSG_RESULT([${PYTHON3}${PYTHON3_VERSION_REPORT}])
+        AC_MSG_RESULT([${PYTHON3}${PYTHON3_VERSION_INFO_REPORT}])
         AC_SUBST([PYTHON3], [${PYTHON3}])
         AM_CONDITIONAL([HAVE_PYTHON3], [test -n "${PYTHON3}" && test "${PYTHON3}" != "no"])
         AS_IF([test -n "${PYTHON3}" && test "${PYTHON3}" != "no"], [
+            AC_MSG_CHECKING([python3 build sys.version])
+            dnl Can have extra lines about compiler used, etc.
+            PYTHON3_VERSION_REPORT="`${PYTHON3} -c 'import sys; print(sys.version);' | tr '\n' ' '`" \
+            || PYTHON3_VERSION_REPORT=""
+            AC_MSG_RESULT([${PYTHON3_VERSION_REPORT}])
+
+            AC_MSG_CHECKING([python3 sys.path used to search for modules])
+            PYTHON3_SYSPATH_REPORT="`${PYTHON3} -c 'import sys; print(sys.path);'`" \
+            || PYTHON3_SYSPATH_REPORT=""
+            AC_MSG_RESULT([${PYTHON3_SYSPATH_REPORT}])
+
             export PYTHON3
             AC_CACHE_CHECK([python3 site-packages location], [nut_cv_PYTHON3_SITE_PACKAGES], [
                 nut_cv_PYTHON3_SITE_PACKAGES="`${PYTHON3} -c 'import site; print(site.getsitepackages().pop(0))'`"
diff --git a/m4/nut_compiler_family.m4 b/m4/nut_compiler_family.m4
index 361a77a444..b6e5f06fc3 100644
--- a/m4/nut_compiler_family.m4
+++ b/m4/nut_compiler_family.m4
@@ -2,6 +2,9 @@ dnl detect if current compiler is clang or gcc (or...)
 
 AC_DEFUN([NUT_COMPILER_FAMILY],
 [
+if test -z "${nut_compiler_family_seen}"; then
+  nut_compiler_family_seen=yes
+
   CC_VERSION_FULL="`LANG=C LC_ALL=C $CC --version 2>&1`"   || CC_VERSION_FULL=""
   CXX_VERSION_FULL="`LANG=C LC_ALL=C $CXX --version 2>&1`" || CXX_VERSION_FULL=""
   CPP_VERSION_FULL="`LANG=C LC_ALL=C $CPP --version 2>&1`" || CPP_VERSION_FULL=""
@@ -86,6 +89,7 @@ AC_DEFUN([NUT_COMPILER_FAMILY],
   AS_IF([test "x$CC_VERSION" = x],  [CC_VERSION="`echo "${CC_VERSION_FULL}" | head -1`"])
   AS_IF([test "x$CXX_VERSION" = x], [CXX_VERSION="`echo "${CXX_VERSION_FULL}" | head -1`"])
   AS_IF([test "x$CPP_VERSION" = x], [CPP_VERSION="`echo "${CPP_VERSION_FULL}" | head -1`"])
+fi
 ])
 
 AC_DEFUN([NUT_CHECK_COMPILE_FLAG],
diff --git a/scripts/HP-UX/makedepot.sh b/scripts/HP-UX/makedepot.sh
index 698bccf44b..82a47db2c0 100755
--- a/scripts/HP-UX/makedepot.sh
+++ b/scripts/HP-UX/makedepot.sh
@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
-set -x 
+set -x
 
 CUR_DIR=$(pwd)
 TOP_DIR=$CUR_DIR/../..
@@ -26,5 +26,4 @@ cd $CUR_DIR
 swpackage -s nut.psf -d $CUR_DIR/nut.depot; \
 #tar cvf nut.depot.tar nut.depot
 #gzip nut.depot.tar
-echo "Execution completed" 
-
+echo "Execution completed"
diff --git a/scripts/Makefile.am b/scripts/Makefile.am
index f0f59aa877..194e95840a 100644
--- a/scripts/Makefile.am
+++ b/scripts/Makefile.am
@@ -25,32 +25,35 @@ EXTRA_DIST = \
     upower/95-upower-hid.rules \
     usb_resetter/README.adoc \
     usb_resetter/nut-driver.service \
+    valgrind/README.adoc \
+    valgrind/.valgrind.supp \
+    valgrind/valgrind.sh \
     Windows/halt.c \
     Windows/Makefile
 
 SUBDIRS = augeas devd hotplug installer python systemd udev ufw Solaris Windows upsdrvsvcctl
 
-SPELLCHECK_SRC = README.adoc RedHat/README.adoc usb_resetter/README.adoc
+SPELLCHECK_SRC = README.adoc RedHat/README.adoc usb_resetter/README.adoc valgrind/README.adoc
 
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
-#	+$(MAKE) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+#	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 # NOTE: Portable suffix rules do not allow prerequisites, so we shim them here
 # by a wildcard target in case the make implementation can put the two together.
 *-spellchecked: Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 
 .sample.sample-spellchecked:
-	+$(MAKE) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 .in.in-spellchecked:
-	+$(MAKE) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 spellcheck spellcheck-interactive spellcheck-sortdict:
-	+$(MAKE) -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC="$(SPELLCHECK_SRC)" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -f $(top_builddir)/docs/Makefile MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC="$(SPELLCHECK_SRC)" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 CLEANFILES = *-spellchecked RedHat/*-spellchecked usb_resetter/*-spellchecked
 
diff --git a/scripts/Solaris/Makefile.am b/scripts/Solaris/Makefile.am
index 3f01ec6034..3fad462879 100644
--- a/scripts/Solaris/Makefile.am
+++ b/scripts/Solaris/Makefile.am
@@ -86,7 +86,7 @@ check-local: $(SOLARIS_CHECK_TARGETS)
 
 check-local-solaris-smf: $(SOLARIS_SMF_MANIFESTS)
 	@[ -x /usr/sbin/svccfg ] || { echo "WARNING : Target $@ skipped due to absent /usr/sbin/svccfg" >&2; return 0; } ; \
-	 RES=0 ; for F in $^ ; do \
+	 RES=0 ; for F in $? ; do \
 	    echo "  SVCCFG-VALIDATE  $$F"; \
 	    /usr/sbin/svccfg validate "$$F" || RES=$$? ; \
 	 done; exit $$RES
@@ -96,7 +96,7 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/Solaris/nut-driver.xml.in b/scripts/Solaris/nut-driver.xml.in
index 81e142ddea..fffd368db9 100644
--- a/scripts/Solaris/nut-driver.xml.in
+++ b/scripts/Solaris/nut-driver.xml.in
@@ -2,14 +2,14 @@
 <!DOCTYPE service_bundle SYSTEM "/usr/share/lib/xml/dtd/service_bundle.dtd.1">
 <!--
 #
-# Copyright 2016 - 2023 Jim Klimov
+# Copyright 2016 - 2024 Jim Klimov
 # Template manifest for instantiated NUT drivers
 #
 -->
 
 <service_bundle type='manifest' name='nut-driver'>
 
-	<service name='system/power/nut-driver' type='service' version='3'>
+	<service name='system/power/nut-driver' type='service' version='4'>
 
 	<!--
 	  Wait for all local and usr filesystem to be mounted - project is
@@ -85,13 +85,13 @@
 		<exec_method
 		type='method'
 		name='start'
-		exec='/sbin/sh -c &apos;NUTDEV="`@NUT_LIBEXECDIR@/nut-driver-enumerator.sh --get-device-for-service %i`" &amp;&amp; [ -n "$NUTDEV" ] || { echo "FATAL: Could not find a NUT device section for service unit %i" >&amp;2 ; exit 1 ; } ; SMF_FMRI=svc:/system/power/nut-server:default @NUT_DATADIR@/solaris-smf/method/svc-nut-server create_run_dir &amp;&amp; @SBINDIR@/upsdrvctl %m "$NUTDEV"&apos;'
+		exec='/sbin/sh -c &apos;NUTDEV="`@NUT_LIBEXECDIR@/nut-driver-enumerator.sh --get-device-for-service %i`" &amp;&amp; [ -n "$NUTDEV" ] || { echo "FATAL: Could not find a NUT device section for service unit %i" >&amp;2 ; exit 1 ; } ; SMF_FMRI=svc:/system/power/nut-server:default @NUT_DATADIR@/solaris-smf/method/svc-nut-server create_run_dir &amp;&amp; NUT_QUIET_INIT_NDE_WARNING=true @SBINDIR@/upsdrvctl %m "$NUTDEV"&apos;'
 		timeout_seconds='0'/>
 
 		<exec_method
 		type='method'
 		name='stop'
-		exec='/sbin/sh -c &apos;NUTDEV="`@NUT_LIBEXECDIR@/nut-driver-enumerator.sh --get-device-for-service %i`" &amp;&amp; [ -n "$NUTDEV" ] || { echo "FATAL: Could not find a NUT device section for service unit %i" >&amp;2 ; exit 1 ; } ; @SBINDIR@/upsdrvctl %m "$NUTDEV"&apos;'
+		exec='/sbin/sh -c &apos;NUTDEV="`@NUT_LIBEXECDIR@/nut-driver-enumerator.sh --get-device-for-service %i`" &amp;&amp; [ -n "$NUTDEV" ] || { echo "FATAL: Could not find a NUT device section for service unit %i" >&amp;2 ; exit 1 ; } ; NUT_QUIET_INIT_NDE_WARNING=true @SBINDIR@/upsdrvctl %m "$NUTDEV"&apos;'
 		timeout_seconds='60' />
 
 	<!-- Note: reload support is currently limited to configuration options
diff --git a/scripts/Windows/Makefile.am b/scripts/Windows/Makefile.am
index 52e4d927f8..abbfd32a37 100644
--- a/scripts/Windows/Makefile.am
+++ b/scripts/Windows/Makefile.am
@@ -77,7 +77,7 @@ SPELLCHECK_SRC = README.adoc DriverInstaller/README.adoc Installer/README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/Windows/build-mingw-nut.sh b/scripts/Windows/build-mingw-nut.sh
index a39765fb00..e36c14de3f 100755
--- a/scripts/Windows/build-mingw-nut.sh
+++ b/scripts/Windows/build-mingw-nut.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # NOTE: bash syntax (non-POSIX script) is used below!
 #
@@ -24,7 +24,7 @@ DLLLDD_SOURCED=true . "${SCRIPTDIR}/dllldd.sh"
 
 # This should match the tarball and directory name,
 # if a stable version is used:
-[ -n "$VER_OPT" ] || VER_OPT=2.8.1
+[ -n "$VER_OPT" ] || VER_OPT=2.8.2
 DEBUG=true
 
 # default to 32bits build
@@ -105,8 +105,11 @@ if [ "$cmd" == "all64" ] || [ "$cmd" == "b64" ] || [ "$cmd" == "all32" ] || [ "$
 	# Note: _WIN32_WINNT>=0x0600 is needed for inet_ntop in mingw headers
 	# and the value 0xffff is anyway forced into some components at least
 	# by netsnmp cflags.
-	export CFLAGS+=" -D_POSIX=1 -D_POSIX_C_SOURCE=200112L -I${ARCH_PREFIX}/include/ -D_WIN32_WINNT=0xffff"
-	export CXXFLAGS+=" -D_POSIX=1 -D_POSIX_C_SOURCE=200112L -I${ARCH_PREFIX}/include/ -D_WIN32_WINNT=0xffff"
+	# _POSIX_THREAD_SAFE_FUNCTIONS whould help with localtime_r() gmtime_r()
+	# on recent mingw releases (as of 2019), per
+	# https://stackoverflow.com/questions/18551409/localtime-r-support-on-mingw
+	export CFLAGS+=" -D_POSIX=1 -D_POSIX_C_SOURCE=200112L -D_POSIX_THREAD_SAFE_FUNCTIONS=200112L -I${ARCH_PREFIX}/include/ -D_WIN32_WINNT=0xffff"
+	export CXXFLAGS+=" -D_POSIX=1 -D_POSIX_C_SOURCE=200112L -D_POSIX_THREAD_SAFE_FUNCTIONS=200112L -I${ARCH_PREFIX}/include/ -D_WIN32_WINNT=0xffff"
 	export LDFLAGS+=" -L${ARCH_PREFIX}/lib/"
 
 	KEEP_NUT_REPORT_FEATURE_FLAG=""
@@ -116,18 +119,34 @@ if [ "$cmd" == "all64" ] || [ "$cmd" == "b64" ] || [ "$cmd" == "all32" ] || [ "$
 
 	# Note: installation prefix here is "/" and desired INSTALL_DIR
 	# location is passed to `make install` as DESTDIR below.
+	# FIXME: Implement support for --without-pkg-config in m4 and use it
+	RES_CFG=0
 	$CONFIGURE_SCRIPT $HOST_FLAG $BUILD_FLAG --prefix=/ \
 	    $KEEP_NUT_REPORT_FEATURE_FLAG \
 	    PKG_CONFIG_PATH="${ARCH_PREFIX}/lib/pkgconfig" \
-	    --without-pkg-config --with-all=auto \
+	    --with-all=auto \
+	    --with-doc="man=auto html-single=auto html-chunked=skip pdf=skip" \
 	    --without-systemdsystemunitdir \
 	    --with-pynut=app \
 	    --with-augeas-lenses-dir=/augeas-lenses \
 	    --enable-Werror \
-	|| exit
-	echo "$0: configure phase complete ($?)" >&2
+	|| RES_CFG=$?
+	echo "$0: configure phase complete ($RES_CFG)" >&2
+	[ x"$RES_CFG" = x0 ] || exit $RES_CFG
 
+	echo "Configuration finished, starting make" >&2
+	if [ -n "$PARMAKE_FLAGS" ]; then
+		echo "For parallel builds, '$PARMAKE_FLAGS' options would be used" >&2
+	fi
+	if [ -n "$MAKEFLAGS" ]; then
+		echo "Generally, MAKEFLAGS='$MAKEFLAGS' options would be passed" >&2
+	fi
+
+	# FIXME: parameterize ${MAKE} ?
 	make 1>/dev/null || exit
+	make doc 1>/dev/null || exit
+	make -k man-man html-man 1>/dev/null || true
+	(cd docs && make check) 1>/dev/null || exit
 	echo "$0: build phase complete ($?)" >&2
 
 	if [ "x$INSTALL_WIN_BUNDLE" = xtrue ] ; then
@@ -152,7 +171,7 @@ if [ "$cmd" == "all64" ] || [ "$cmd" == "b64" ] || [ "$cmd" == "all32" ] || [ "$
 		# on a modern Windows one could go to their installed "sbin" to
 		#   mklink .\libupsclient-3.dll ..\bin\libupsclient-3.dll
 		(cd "$INSTALL_DIR/bin" && ln libupsclient*.dll ../sbin/)
-		(cd "$INSTALL_DIR/cgi-bin" && ln ../bin/libupsclient*.dll ./) \
+		(cd "$INSTALL_DIR/cgi-bin" 2>/dev/null && ln ../bin/libupsclient*.dll ./) \
 		|| echo "NOTE: FAILED to process OPTIONAL cgi-bin directory; was NUT CGI enabled?" >&2
 
 		echo "NOTE: Adding third-party dependency libraries for each installed program" >&2
@@ -172,7 +191,7 @@ if [ "$cmd" == "all64" ] || [ "$cmd" == "b64" ] || [ "$cmd" == "all32" ] || [ "$
 		(cd "$INSTALL_DIR/sbin" && { DESTDIR="$INSTALL_DIR" dllldddir . | while read D ; do ln -f ../bin/"`basename "$D"`" ./ ; done ; } ) || true
 
 		# Hardlink libraries for cgi-bin if present:
-		(cd "$INSTALL_DIR/cgi-bin" && { DESTDIR="$INSTALL_DIR" dllldddir . | while read D ; do ln -f ../bin/"`basename "$D"`" ./ ; done ; } ) \
+		(cd "$INSTALL_DIR/cgi-bin" 2>/dev/null && { DESTDIR="$INSTALL_DIR" dllldddir . | while read D ; do ln -f ../bin/"`basename "$D"`" ./ ; done ; } ) \
 		|| echo "NOTE: FAILED to process OPTIONAL cgi-bin directory; was NUT CGI enabled?" >&2
 	fi
 
diff --git a/scripts/Windows/wininit.c b/scripts/Windows/wininit.c
index f86cd2bf7b..527a87e831 100644
--- a/scripts/Windows/wininit.c
+++ b/scripts/Windows/wininit.c
@@ -1,7 +1,9 @@
 /* wininit.c - MS Windows service which replace the init script
+               (compiled as "nut.exe")
 
    Copyright (C)
 	2010	Frederic Bohe <fredericbohe@eaton.com>
+	2021-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -56,18 +58,19 @@ static void print_event(DWORD priority, const char * fmt, ...)
 	ret = vsnprintf(buf, LARGEBUF, fmt, ap);
 	va_end(ap);
 
-	if(ret<0) {
+	if (ret < 0) {
 		return;
 	}
 
-	if( !service_flag ) {
+	if (!service_flag) {
 		upslogx(LOG_ERR, "EventLog : %s\n",buf);
 	}
 
 	EventSource = RegisterEventSource(NULL, SVCNAME);
 
-	if( NULL != EventSource ) {
-		ReportEvent( EventSource,	/* event log handle */
+	if (NULL != EventSource) {
+		ReportEvent(
+				EventSource,	/* event log handle */
 				priority,	/* event type */
 				0,		/* event category */
 				SVC_EVENT,	/* event identifier */
@@ -81,7 +84,7 @@ static void print_event(DWORD priority, const char * fmt, ...)
 
 	}
 
-	if( buf )
+	if (buf)
 		free(buf);
 }
 
@@ -93,9 +96,9 @@ static DWORD create_process(char * command)
 	BOOL res;
 	DWORD LastError;
 
-	memset(&StartupInfo,0,sizeof(STARTUPINFO));
+	memset(&StartupInfo, 0, sizeof(STARTUPINFO));
 	StartupInfo.cb = sizeof(StartupInfo);
-	memset(&ProcessInformation,0,sizeof(ProcessInformation));
+	memset(&ProcessInformation, 0, sizeof(ProcessInformation));
 
 	res = CreateProcess(
 			NULL,
@@ -111,7 +114,7 @@ static DWORD create_process(char * command)
 			);
 	LastError = GetLastError();
 
-	if( res == 0 ) {
+	if (res == 0) {
 		print_event(LOG_ERR, "Can't create process %s : %d", command, LastError);
 		return 0;
 	}
@@ -119,70 +122,106 @@ static DWORD create_process(char * command)
 	return  ProcessInformation.dwProcessId;
 }
 
+/* Return a statically allocated buffer, no need to free() it */
+static const char * makearg_debug(void)
+{
+	static char	buf[SMALLBUF];
+	char	*p = buf;
+	size_t	i;
+
+	if (nut_debug_level < 1)
+		return("");
+
+	*p = '-';
+	p++;
+	for (i = 0; (i < (size_t)nut_debug_level && i < (sizeof(buf) - 2)); i++, p++) {
+		*p = 'D';
+	}
+	*p = '\0';
+
+	return (const char *)buf;
+}
+
 /* return PID of created process or 0 on failure */
-static DWORD run_drivers()
+static DWORD run_drivers(void)
 {
 	char command[MAX_PATH];
 	char *path;
 
 	path = getfullpath(PATH_BIN);
-	snprintf(command,sizeof(command),"%s\\upsdrvctl.exe start",path);
+	if (nut_debug_level < 1) {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe start", path);
+	} else {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe -d %s start",
+			path, makearg_debug());
+	}
 	free(path);
 	return create_process(command);
 }
 
 /* return PID of created process or 0 on failure */
-static DWORD stop_drivers()
+static DWORD stop_drivers(void)
 {
 	char command[MAX_PATH];
 	char *path;
 
 	path = getfullpath(PATH_BIN);
-	snprintf(command,sizeof(command),"%s\\upsdrvctl.exe stop",path);
+	if (nut_debug_level < 1) {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe stop", path);
+	} else {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe %s stop",
+			path, makearg_debug());
+	}
 	free(path);
 	return create_process(command);
 }
 
 /* return PID of created process or 0 on failure */
-static void run_upsd()
+static void run_upsd(void)
 {
 	char command[MAX_PATH];
 	char *path;
 
 	path = getfullpath(PATH_SBIN);
-	snprintf(command,sizeof(command),"%s\\upsd.exe",path);
+	snprintf(command, sizeof(command), "%s\\upsd.exe", path);
+	if (nut_debug_level > 0) {
+		snprintfcat(command, sizeof(command), " %s", makearg_debug());
+	}
 	free(path);
 	upsd_pid = create_process(command);
 }
 
-static void stop_upsd()
+static void stop_upsd(void)
 {
-	if ( sendsignal( UPSD_PIPE_NAME, COMMAND_STOP ) ) {
-		print_event(LOG_ERR, "Error stopping upsd (%d)",GetLastError());
+	if (sendsignal(UPSD_PIPE_NAME, COMMAND_STOP, 0)) {
+		print_event(LOG_ERR, "Error stopping upsd (%d)", GetLastError());
 	}
 }
 
 /* return PID of created process or 0 on failure */
-static void run_upsmon()
+static void run_upsmon(void)
 {
 	char command[MAX_PATH];
 	char *path;
 
 	path = getfullpath(PATH_SBIN);
-	snprintf(command,sizeof(command),"%s\\upsmon.exe",path);
+	snprintf(command, sizeof(command), "%s\\upsmon.exe", path);
+	if (nut_debug_level > 0) {
+		snprintfcat(command, sizeof(command), " %s", makearg_debug());
+	}
 	free(path);
 	upsmon_pid = create_process(command);
 }
 
-static void stop_upsmon()
+static void stop_upsmon(void)
 {
-	if ( sendsignal( UPSMON_PIPE_NAME, COMMAND_STOP ) ) {
-		print_event(LOG_ERR, "Error stopping upsmon (%d)",GetLastError());
+	if (sendsignal(UPSMON_PIPE_NAME, COMMAND_STOP, 0)) {
+		print_event(LOG_ERR, "Error stopping upsmon (%d)", GetLastError());
 	}
 }
 
 /* Return 0 if powerdown flag is set */
-static DWORD test_powerdownflag()
+static DWORD test_powerdownflag(void)
 {
 	char command[MAX_PATH];
 	char *path;
@@ -195,12 +234,15 @@ static DWORD test_powerdownflag()
 	int timeout = 500;
 
 	path = getfullpath(PATH_SBIN);
-	snprintf(command,sizeof(command),"%s\\upsmon.exe -K",path);
+	snprintf(command, sizeof(command), "%s\\upsmon.exe -K", path);
+	if (nut_debug_level > 0) {
+		snprintfcat(command, sizeof(command), " %s", makearg_debug());
+	}
 	free(path);
 
-	memset(&StartupInfo,0,sizeof(STARTUPINFO));
+	memset(&StartupInfo, 0, sizeof(STARTUPINFO));
 	StartupInfo.cb = sizeof(StartupInfo);
-	memset(&ProcessInformation,0,sizeof(ProcessInformation));
+	memset(&ProcessInformation, 0, sizeof(ProcessInformation));
 
 	res = CreateProcess(
 			NULL,
@@ -216,15 +258,15 @@ static DWORD test_powerdownflag()
 			);
 	LastError = GetLastError();
 
-	if( res == 0 ) {
+	if (res == 0) {
 		print_event(LOG_ERR, "Can't create process %s : %d", command, LastError);
 		return 1;
 	}
 
-	while( i > 0) {
+	while (i > 0) {
 		res = GetExitCodeProcess(ProcessInformation.hProcess, &status);
-		if( res != 0) {
-			if( status != STILL_ACTIVE) {
+		if (res != 0) {
+			if (status != STILL_ACTIVE) {
 				return status;
 			}
 		}
@@ -235,13 +277,18 @@ static DWORD test_powerdownflag()
 	return 1;
 }
 
-static DWORD shutdown_ups()
+static DWORD shutdown_ups(void)
 {
 	char command[MAX_PATH];
 	char *path;
 
 	path = getfullpath(PATH_BIN);
-	snprintf(command,sizeof(command),"%s\\upsdrvctl.exe shutdown",path);
+	if (nut_debug_level < 1) {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe shutdown", path);
+	} else {
+		snprintf(command, sizeof(command), "%s\\upsdrvctl.exe -d %s shutdown",
+			path, makearg_debug());
+	}
 	free(path);
 	return create_process(command);
 }
@@ -254,53 +301,58 @@ static int parse_nutconf(BOOL start_flag)
 	char	buf[SMALLBUF];
 	char	fullname[SMALLBUF];
 
-	snprintf(fn,sizeof(fn),"%s/nut.conf",confpath());
+	snprintf(fn, sizeof(fn), "%s/nut.conf", confpath());
 
 	nutf = fopen(fn, "r");
-	if(nutf == NULL) {
-		snprintf(buf,sizeof(buf),"Error opening %s",fn);
-		print_event(LOG_ERR,buf);
+	if (nutf == NULL) {
+		snprintf(buf, sizeof(buf), "Error opening %s", fn);
+		print_event(LOG_ERR, buf);
 		return 0;
 	}
 
-	while( fgets(buf,sizeof(buf),nutf) != NULL ) {
-		if(buf[0] != '#') {
-			if( strstr(buf,"standalone") != NULL ||
-					strstr(buf,"netserver") != NULL ) {
-				if( start_flag == NUT_START ) {
-					print_event(LOG_INFO,"Starting drivers");
+	while (fgets(buf, sizeof(buf), nutf) != NULL) {
+		if (buf[0] != '#') {
+			if (strstr(buf, "standalone") != NULL
+			||  strstr(buf, "netserver") != NULL
+			) {
+				if (start_flag == NUT_START) {
+					print_event(LOG_INFO, "Starting drivers");
 					run_drivers();
-					print_event(LOG_INFO,"Starting upsd");
+					print_event(LOG_INFO, "Starting upsd");
 					run_upsd();
+
 					/* Wait a moment for the drivers to start */
 					Sleep(5000);
-					print_event(LOG_INFO,"Starting upsmon");
+					print_event(LOG_INFO, "Starting upsmon");
 					run_upsmon();
 					return 1;
 				}
 				else {
-					print_event(LOG_INFO,"stop upsd");
+					print_event(LOG_INFO, "Stopping upsd");
 					stop_upsd();
-					print_event(LOG_INFO,"stop drivers");
+					print_event(LOG_INFO, "Stopping drivers");
 					stop_drivers();
-					print_event(LOG_INFO,"stop upsmon");
+					print_event(LOG_INFO, "Stopping upsmon");
 					stop_upsmon();
-					/* Give a chance to upsmon to write the POWERDOWNFLAG  file */
+
+					/* Give upsmon a chance to write the POWERDOWNFLAG file */
 					Sleep(1000);
-					if( test_powerdownflag() == 0 ) {
-						print_event(LOG_INFO,"shutdown ups");
+					if (test_powerdownflag() == 0) {
+						print_event(LOG_INFO, "Shutting down the UPS");
 						shutdown_ups();
 					}
-					print_event(LOG_INFO,"End of NUT stop");
+					print_event(LOG_INFO, "End of NUT stop");
 					return 1;
 				}
 			}
-			if( strstr(buf,"netclient") != NULL ) {
-				if( start_flag == NUT_START ) {
+			if (strstr(buf, "netclient") != NULL) {
+				if (start_flag == NUT_START) {
+					print_event(LOG_INFO, "Starting upsmon (client only)");
 					run_upsmon();
 					return 1;
 				}
 				else {
+					print_event(LOG_INFO, "Stopping upsmon (client only)");
 					stop_upsmon();
 					return 1;
 				}
@@ -308,9 +360,12 @@ static int parse_nutconf(BOOL start_flag)
 		}
 	}
 
-	GetFullPathName(fn,sizeof(fullname),fullname,NULL);
-	snprintf(buf,sizeof(buf),"nut disabled, please adjust the configuration to your needs. Then set MODE to a suitable value in %s to enable it.",fullname);
-	print_event(LOG_ERR,buf);
+	GetFullPathName(fn, sizeof(fullname), fullname, NULL);
+	snprintf(buf, sizeof(buf),
+		"NUT disabled, please adjust the configuration to your needs. "
+		"Then set MODE to a suitable value in %s to enable it.",
+		fullname);
+	print_event(LOG_ERR, buf);
 	return 0;
 }
 
@@ -320,12 +375,12 @@ static int SvcInstall(const char * SvcName, const char * args)
 	SC_HANDLE Service;
 	TCHAR Path[MAX_PATH];
 
-	if( !GetModuleFileName( NULL, Path, MAX_PATH ) ) {
+	if (!GetModuleFileName(NULL, Path, MAX_PATH)) {
 		printf("Cannot install service (%d)\n", (int)GetLastError());
 		return EXIT_FAILURE;
 	}
 
-	if( args != NULL ) {
+	if (args != NULL) {
 		snprintfcat(Path, sizeof(Path), " %s", args);
 	}
 
@@ -369,6 +424,45 @@ static int SvcInstall(const char * SvcName, const char * args)
 	return EXIT_SUCCESS;
 }
 
+/* Returns a positive value if the service name exists
+ * -2 if we can not open the service manager
+ * -1 if we can not open the service itself
+ * +1 SvcName exists
+ */
+static int SvcExists(const char * SvcName)
+{
+	SC_HANDLE SCManager;
+	SC_HANDLE Service;
+
+	SCManager = OpenSCManager(
+			NULL,			/* local computer */
+			NULL,			/* ServicesActive database */
+			SC_MANAGER_ALL_ACCESS);	/* full access rights */
+
+	if (NULL == SCManager) {
+		upsdebugx(1, "OpenSCManager failed (%d)\n", (int)GetLastError());
+		return -2;
+	}
+
+	Service = OpenService(
+			SCManager,	/* SCM database */
+			SvcName,	/* name of service */
+			DELETE);	/* need delete access */
+
+	if (Service == NULL) {
+		upsdebugx(1, "OpenService failed (%d) for \"%s\"\n",
+			(int)GetLastError(), SvcName);
+		CloseServiceHandle(SCManager);
+		return -1;
+	}
+
+	CloseServiceHandle(Service);
+	CloseServiceHandle(SCManager);
+
+	upsdebugx(1, "Service \"%s\" seems to exist", SvcName);
+	return 1;
+}
+
 static int SvcUninstall(const char * SvcName)
 {
 	SC_HANDLE SCManager;
@@ -395,11 +489,11 @@ static int SvcUninstall(const char * SvcName)
 		return EXIT_FAILURE;
 	}
 
-	if (! DeleteService(Service) )  {
-		upslogx(LOG_ERR,"DeleteService failed (%d)\n", (int)GetLastError());
+	if (!DeleteService(Service))  {
+		upslogx(LOG_ERR, "DeleteService failed (%d)\n", (int)GetLastError());
 	}
 	else {
-		upslogx(LOG_ERR,"Service deleted successfully\n");
+		upslogx(LOG_ERR, "Service deleted successfully\n");
 	}
 
 	CloseServiceHandle(Service);
@@ -408,7 +502,8 @@ static int SvcUninstall(const char * SvcName)
 	return EXIT_SUCCESS;
 }
 
-static void ReportSvcStatus(   DWORD CurrentState,
+static void ReportSvcStatus(
+		DWORD CurrentState,
 		DWORD Win32ExitCode,
 		DWORD WaitHint)
 {
@@ -422,8 +517,9 @@ static void ReportSvcStatus(   DWORD CurrentState,
 		SvcStatus.dwControlsAccepted = 0;
 	else SvcStatus.dwControlsAccepted = SERVICE_ACCEPT_STOP | SERVICE_ACCEPT_SHUTDOWN;
 
-	if ( (CurrentState == SERVICE_RUNNING) ||
-			(CurrentState == SERVICE_STOPPED) ) {
+	if ( (CurrentState == SERVICE_RUNNING)
+	||   (CurrentState == SERVICE_STOPPED)
+	) {
 		SvcStatus.dwCheckPoint = 0;
 	}
 	else {
@@ -431,10 +527,10 @@ static void ReportSvcStatus(   DWORD CurrentState,
 	}
 
 	/* report the status of the service to the SCM */
-	SetServiceStatus( SvcStatusHandle, &SvcStatus );
+	SetServiceStatus(SvcStatusHandle, &SvcStatus);
 }
 
-static void WINAPI SvcCtrlHandler( DWORD Ctrl )
+static void WINAPI SvcCtrlHandler(DWORD Ctrl)
 {
 	switch(Ctrl)
 	{
@@ -463,7 +559,7 @@ static void SvcStart(char * SvcName)
 			SvcName,
 			SvcCtrlHandler);
 
-	if( !SvcStatusHandle ) {
+	if (!SvcStatusHandle) {
 		upslogx(LOG_ERR, "RegisterServiceCtrlHandler\n");
 		return;
 	}
@@ -472,7 +568,7 @@ static void SvcStart(char * SvcName)
 	SvcStatus.dwServiceSpecificExitCode = 0;
 
 	/* Report initial status to the SCM */
-	ReportSvcStatus( SERVICE_START_PENDING, NO_ERROR, 3000 );
+	ReportSvcStatus(SERVICE_START_PENDING, NO_ERROR, 3000);
 }
 
 static void SvcReady(void)
@@ -483,11 +579,11 @@ static void SvcReady(void)
 			FALSE,	/* not signaled */
 			NULL);	/* no name */
 
-	if( svc_stop == NULL ) {
-		ReportSvcStatus( SERVICE_STOPPED, NO_ERROR, 0);
+	if (svc_stop == NULL) {
+		ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
 		return;
 	}
-	ReportSvcStatus( SERVICE_RUNNING, NO_ERROR, 0);
+	ReportSvcStatus(SERVICE_RUNNING, NO_ERROR, 0);
 }
 
 static void close_all(void)
@@ -500,19 +596,19 @@ static void close_all(void)
 
 }
 
-static void WINAPI SvcMain( DWORD argc, LPTSTR *argv )
+static void WINAPI SvcMain(DWORD argc, LPTSTR *argv)
 {
 	DWORD	ret;
 	HANDLE	handles[MAXIMUM_WAIT_OBJECTS];
 	int	maxhandle = 0;
 	pipe_conn_t	*conn;
-	DWORD priority;
-	char * buf;
+	DWORD	priority;
+	char	*buf;
 
 	NUT_UNUSED_VARIABLE(argc);
 	NUT_UNUSED_VARIABLE(argv);
 
-	if(service_flag) {
+	if (service_flag) {
 		SvcStart(SVCNAME);
 	}
 
@@ -521,79 +617,81 @@ static void WINAPI SvcMain( DWORD argc, LPTSTR *argv )
 	/* create a console which will be inherited by children */
 	AllocConsole();
 
-	print_event(LOG_INFO,"Starting");
+	print_event(LOG_INFO, "Starting");
 
 	/* pipe for event log proxy */
 	pipe_create(EVENTLOG_PIPE_NAME);
 
 	/* parse nut.conf and start relevant processes */
-	if ( parse_nutconf(NUT_START) == 0 ) {
+	if (parse_nutconf(NUT_START) == 0) {
 		print_event(LOG_INFO, "exiting");
-		if( service_flag ) {
-			ReportSvcStatus( SERVICE_STOPPED, NO_ERROR, 0);
+		if (service_flag) {
+			ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
 		}
 		return;
 	}
 
-	if(service_flag) {
+	if (service_flag) {
 		SvcReady();
 	}
 
 	while (1) {
 		maxhandle = 0;
-		memset(&handles,0,sizeof(handles));
+		memset(&handles, 0, sizeof(handles));
 
 		/* Wait on the read IO of each connections */
 		for (conn = pipe_connhead; conn; conn = conn->next) {
 			handles[maxhandle] = conn->overlapped.hEvent;
 			maxhandle++;
 		}
+
 		/* Add the new pipe connected event */
 		handles[maxhandle] = pipe_connection_overlapped.hEvent;
 		maxhandle++;
 
 		/* Add SCM event handler in service mode*/
-		if(service_flag) {
+		if (service_flag) {
 			handles[maxhandle] = svc_stop;
 			maxhandle++;
 		}
 
-		ret = WaitForMultipleObjects(maxhandle,handles,FALSE,INFINITE);
+		ret = WaitForMultipleObjects(maxhandle, handles, FALSE, INFINITE);
 
 		if (ret == WAIT_FAILED) {
 			print_event(LOG_ERR, "Wait failed");
 			return;
 		}
 
-		if( handles[ret] == svc_stop && service_flag ) {
+		if (handles[ret] == svc_stop && service_flag) {
 			parse_nutconf(NUT_STOP);
-			if(service_flag) {
+			if (service_flag) {
 				print_event(LOG_INFO, "Exiting");
 				close_all();
-				ReportSvcStatus( SERVICE_STOPPED, NO_ERROR, 0);
+				ReportSvcStatus(SERVICE_STOPPED, NO_ERROR, 0);
 			}
 			return;
 		}
 
 		/* Retrieve the signaled connection */
-		for(conn = pipe_connhead; conn != NULL; conn = conn->next) {
-			if( conn->overlapped.hEvent == handles[ret-WAIT_OBJECT_0]) {
+		for (conn = pipe_connhead; conn != NULL; conn = conn->next) {
+			if (conn->overlapped.hEvent == handles[ret - WAIT_OBJECT_0]) {
 				break;
 			}
 		}
-		/* a new pipe connection has been signaled */
+
 		if (handles[ret] == pipe_connection_overlapped.hEvent) {
+			/* a new pipe connection has been signaled */
 			pipe_connect();
 		}
-		/* one of the read event handle has been signaled */
 		else {
-			if( conn != NULL) {
-				if( pipe_ready(conn) ) {
+			/* one of the read event handles has been signaled */
+			if (conn != NULL) {
+				if (pipe_ready(conn)) {
 					buf = conn->buf;
-					/* a frame is a DWORD indicating priority followed by an array of char (not necessarily followed by a terminal 0 */
-					priority =*((DWORD *)buf);
+					/* a frame is a DWORD indicating priority followed by an array of char (not necessarily followed by a terminal 0) */
+					priority = *((DWORD *)buf);
 					buf = buf + sizeof(DWORD);
-					print_event(priority,buf);
+					print_event(priority, buf);
 
 					pipe_disconnect(conn);
 				}
@@ -602,40 +700,141 @@ static void WINAPI SvcMain( DWORD argc, LPTSTR *argv )
 	}
 }
 
+static void help(const char *arg_progname)
+{
+	print_banner_once(arg_progname, 2);
+
+	printf("NUT for Windows all-in-one wrapper for driver(s), data server and monitoring client\n");
+	printf("including shutdown and power-off handling (where supported). All together they rely\n");
+	printf("on nut.conf and other files in %s\n", confpath());
+
+	printf("\nUsage: %s {start | stop}\n\n", arg_progname);
+	printf("    start	Install as a service (%s) if not yet done, then `net start` it\n", SVCNAME);
+	printf("    stop	If the service (%s) is installed, command it to `net stop`\n", SVCNAME);
+	printf("Note you may have to run this in an elevated privilege command shell, or use `runas`\n");
+
+	printf("\nUsage: %s [OPTION]\n\n", arg_progname);
+
+	printf("Options (note minus not slash as the control character), one of:\n");
+	printf("    -I	Install as a service (%s)\n", SVCNAME);
+	printf("    -U	Uninstall the service\n");
+	printf("    -N	Run once in non-service mode\n");
+	printf("    -D	Raise debug verbosity (passed to launched NUT programs)\n");
+	printf("    -V	Display NUT version and exit\n");
+	printf("    -h	Display this help and exit\n");	/* also /? but be hush about the one slash */
+}
+
 int main(int argc, char **argv)
 {
-	int i;
-	while ((i = getopt(argc, argv, "+IUN")) != -1) {
+	int	i, default_opterr = opterr;
+	const char	*progname = xbasename(argc > 0 ? argv[0] : "nut.exe");
+
+	if (argc > 1) {
+		if (!strcmp(argv[1], "/?")) {
+			help(progname);
+			return EXIT_SUCCESS;
+		}
+
+		if (!strcmp(argv[1], "stop")) {
+			int ret;
+			if (SvcExists(SVCNAME) < 0)
+				fprintf(stderr, "WARNING: Can not access service \"%s\"", SVCNAME);
+
+			ret = system("net stop \"" SVCNAME "\"");
+			if (ret == 0)
+				return EXIT_SUCCESS;
+			fatalx(EXIT_FAILURE, "FAILED stopping %s: %i", SVCNAME, ret);
+		}
+
+		if (!strcmp(argv[1], "start")) {
+			int ret;
+			if (SvcExists(SVCNAME) < 0) {
+				fprintf(stderr, "WARNING: Can not access service \"%s\", registering first", SVCNAME);
+				SvcInstall(SVCNAME, NULL);
+			}
+
+			ret = system("net start \"" SVCNAME "\"");
+			if (ret == 0)
+				return EXIT_SUCCESS;
+			fatalx(EXIT_FAILURE, "FAILED starting %s: %i", SVCNAME, ret);
+		}
+	}
+
+	/* TODO: Do not warn about unknown args - pass them to SvcMain()
+	 * Currently neutered because that method ignores argc/argv de-facto.
+	 *    opterr = 0;
+	 */
+	while ((i = getopt(argc, argv, "+IUNDVh")) != -1) {
 		switch (i) {
 			case 'I':
-				return SvcInstall(SVCNAME,NULL);
+				return SvcInstall(SVCNAME, NULL);
 			case 'U':
 				return SvcUninstall(SVCNAME);
 			case 'N':
 				service_flag = FALSE;
 				upslogx(LOG_ERR, "Running in non-service mode\n");
 				break;
+			case 'D':
+				nut_debug_level++;
+				break;
+			case 'V':
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(progname, 1);
+				nut_report_config_flags();
+				return EXIT_SUCCESS;
+			case 'h':
+				help(progname);
+				return EXIT_SUCCESS;
 			default:
+				/* Assume console-app start would come up - and pass args
+				 * there, quietly; note that getopt() converts unknown
+				 * chars to '?' so we can not log what exactly was wrong.
+				 */
+				upsdebugx(1, "%s: unknown option ignored "
+					"(maybe SvcMain would use it later)",
+					progname);
 				break;
 		}
 	}
 
 	optind = 0;
+	opterr = default_opterr;
 
 	SERVICE_TABLE_ENTRY DispatchTable[] =
 	{
 		{ SVCNAME, (LPSERVICE_MAIN_FUNCTION) SvcMain },
 		{ NULL, NULL }
 	};
+
 	/* This call returns when the service has stopped */
-	if(service_flag ) {
-		if (!StartServiceCtrlDispatcher( DispatchTable ))
+	if (service_flag) {
+		if (!StartServiceCtrlDispatcher(DispatchTable))
 		{
-			print_event(LOG_ERR, "StartServiceCtrlDispatcher failed : exiting, this is a Windows service which can't be run as a regular application by default. Try -N to start it as a regular application");
+			DWORD LastError = GetLastError();
+
+			if (LastError == ERROR_FAILED_SERVICE_CONTROLLER_CONNECT) {
+				const char *msg = "StartServiceCtrlDispatcher failed: "
+					"exiting. This is a Windows service which can't "
+					"be run as a regular application by default. "
+					"Try -N to start it as a regular application.";
+
+				print_event(LOG_ERR, "%s", msg);
+				fprintf(stderr, "ERROR: %s\n\n", msg);
+
+				if (argc < 2) {
+					help(progname);
+				}
+			} else {
+				print_event(LOG_ERR, "StartServiceCtrlDispatcher failed (%ld): "
+					"exiting", LastError);
+			}
+
+			return EXIT_FAILURE;
 		}
 	}
 	else {
-		SvcMain(argc,argv);
+		SvcMain(argc, argv);
 	}
 
 	return EXIT_SUCCESS;
diff --git a/scripts/augeas/Makefile.am b/scripts/augeas/Makefile.am
index dc5e924dee..106a3a3d67 100644
--- a/scripts/augeas/Makefile.am
+++ b/scripts/augeas/Makefile.am
@@ -28,18 +28,33 @@ dist-hook:
 if HAVE_AUGPARSE
 check-local:
 	@echo "augparse proceeding to lenses verification job..."; \
-	echo "DISABLED for now due to https://github.com/networkupstools/nut/issues/657"
+	 echo "DISABLED for now due to https://github.com/networkupstools/nut/issues/657 -" ; \
+	 echo "as a developer, you can run the tests below manually but not automatically:" ; \
+	 echo "    $(AUGPARSE) -I $(builddir)/ -I $(srcdir)/ $(srcdir)/tests/test_nut.aug" ; \
+	 echo "or 'make check-augeas' or 'make check-augeas-all' in `pwd`"
+
+check-augeas:
+	$(AUGPARSE) -I $(builddir)/ -I $(srcdir)/ $(srcdir)/tests/test_nut.aug
+
+check-augeas-all: check-augeas
+	$(AUGPARSE) -I $(builddir)/ -I $(srcdir)/ $(srcdir)/tests/test_nut_flaky.aug
+	$(AUGPARSE) -I $(builddir)/ -I $(srcdir)/ $(srcdir)/tests/test_nut_fixme.aug
 endif
-# FIXME
-#	augparse -I $(srcdir)/ $(srcdir)/tests/test_nut.aug
 
 if WITH_AUGLENS
 # Now "make install" should cover delivery of Augeas lenses...
-# The "auglensdir" value should be set up by configure
+# The "auglensdir" and "auglenstestsdir" values should be set up by configure
 # The *.aug files are generated by rule above or by autogen.sh and/or configure
  auglens_DATA = \
     nuthostsconf.aug  nutupsconf.aug   nutupsdusers.aug   nutupsschedconf.aug \
     nutnutconf.aug    nutupsdconf.aug  nutupsmonconf.aug  nutupssetconf.aug
+
+ auglenstests_DATA = \
+    tests/test_nut.aug
+else
+ EXTRA_DIST += \
+    nuthostsconf.aug.in  nutupsconf.aug.in   nutupsdusers.aug.in   nutupsschedconf.aug.in \
+    nutnutconf.aug.in    nutupsdconf.aug.in  nutupsmonconf.aug.in  nutupssetconf.aug.in
 endif
 
 MAINTAINERCLEANFILES = Makefile.in .dirstamp
diff --git a/scripts/augeas/gen-nutupsconf-aug.py.in b/scripts/augeas/gen-nutupsconf-aug.py.in
index 6132ccb37b..705d074db2 100755
--- a/scripts/augeas/gen-nutupsconf-aug.py.in
+++ b/scripts/augeas/gen-nutupsconf-aug.py.in
@@ -1,5 +1,7 @@
 #!@PYTHON@
-#   Copyright (C) 2010 - Arnaud Quette <arnaud.quette@gmail.com>
+#   Copyright (C)
+#     2010 -        Arnaud Quette <arnaud.quette@gmail.com>
+#     2020 - 2024   Jim Klimov <jimklimov+nut@gmail.com>
 #
 #   This program is free software; you can redistribute it and/or modify
 #   it under the terms of the GNU General Public License as published by
@@ -50,7 +52,7 @@ def grep(string,list):
 		match = expr.search(text)
 		if match != None:
 			# Exclude comments
-			exprComment = re.compile('(/\*([^*]|(\*+[^*/]))*\*+/)|(//.*)')
+			exprComment = re.compile(r'(/\*([^*]|(\*+[^*/]))*\*+/)|(//.*)')
 			if (exprComment.search(match.string) == None):
 				matchList.append(match.string)
 
@@ -80,7 +82,7 @@ if __name__ == '__main__':
 		if filename not in Exceptionlist:
 			fd = codecs.open(filename, encoding='utf-8')
 			# 1.3/ Grep for the "addvar(..." pattern
-			matchResults = grep ('.*addvar[\ ]*\(.*(VAR_FLAG|VAR_VALUE)*,.*', fd)
+			matchResults = grep (r'.*addvar[\ ]*\(.*(VAR_FLAG|VAR_VALUE)*,.*', fd)
 
 			# 1.4/ Extract variable names
 			for line in matchResults:
diff --git a/scripts/augeas/nutnutconf.aug.in b/scripts/augeas/nutnutconf.aug.in
index 69d6f78c39..640cd0fd61 100644
--- a/scripts/augeas/nutnutconf.aug.in
+++ b/scripts/augeas/nutnutconf.aug.in
@@ -3,6 +3,7 @@ Module: NutNutConf
  Parses @CONFPATH@/nut.conf
 
 Author: Frederic Bohe  <fredericbohe@eaton.com>
+        Jim Klimov     <jimklimov+nut@gmail.com>
 
 About: License
   This file is licensed under the GPL.
@@ -32,15 +33,48 @@ let eol      = Util.eol
 let comment  = Util.comment
 let empty    = Util.empty
 
+(* note different definitions than in other configs - this one is shell-syntax *)
+let bool     = /true|false|"true"|"false"|'true'|'false'/
+let num      = /[0-9]+|"[0-9]+"|'[0-9]+'/
+let num_signed      = /[+-]?[0-9]+|"[+-]?[0-9]+"|'[+-]?[0-9]+'/
+let word     = /[^"#; \t\n]+/
+
+(* Variable: quoted_word *)
+let word_space  = /"[^"\n]+"/
+let quoted_word = /"[^" \t\n]+"|'[^' \t\n]+'/
+
+(* Variable: word_all *)
+let word_all = word_space | word | quoted_word
 
 let nut_possible_mode = "none"
 			| "standalone"
 			| "netserver"
 			| "netclient"
+			| "controlled"
+			| "manual"
 
 let nut_mode = [ sep_spc . key "MODE" . def_sep . sep_spc . store nut_possible_mode . eol ]
 
-let nut_lns  = (nut_mode|comment|empty)*
+let nut_bool_re = "ALLOW_NO_DEVICE"
+                  | "ALLOW_NOT_ALL_LISTENERS"
+                  | "POWEROFF_QUIET"
+
+let nut_bool          = [ sep_spc . key nut_bool_re . def_sep . sep_spc . store bool . eol ]
+
+let nut_num_re = "POWEROFF_WAIT"
+
+let nut_num          = [ sep_spc . key nut_num_re . def_sep . sep_spc . store num . eol ]
+
+let nut_num_signed_re = "NUT_DEBUG_LEVEL"
+
+let nut_num_signed          = [ sep_spc . key nut_num_signed_re . def_sep . sep_spc . store num_signed . eol ]
+
+let nut_word_all_re = "UPSD_OPTIONS"
+                  | "UPSMON_OPTIONS"
+
+let nut_word_all          = [ sep_spc . key nut_word_all_re . def_sep . sep_spc . store word_all . eol ]
+
+let nut_lns  = (nut_mode|nut_bool|nut_num|nut_num_signed|nut_word_all|comment|empty)*
 
 let nut_filter = ( incl "@CONFPATH@/nut.conf" )
 			. Util.stdexcl
diff --git a/scripts/augeas/nutupsconf.aug.tpl b/scripts/augeas/nutupsconf.aug.tpl
index 0f7c66cc71..804ce9e17e 100644
--- a/scripts/augeas/nutupsconf.aug.tpl
+++ b/scripts/augeas/nutupsconf.aug.tpl
@@ -4,7 +4,8 @@ Module: NutUpsConf
 
 Author: Raphael Pinson <raphink@gmail.com>
         Frederic Bohe  <fredericbohe@eaton.com>
-        Arnaud Quette <arnaud.quette@gmail.com>
+        Arnaud Quette  <arnaud.quette@gmail.com>
+        Jim Klimov     <jimklimov+nut@gmail.com>
 
 About: License
   This file is licensed under the GPL.
@@ -34,10 +35,16 @@ let ups_global   = "chroot"
                  | "driverpath"
                  | "maxstartdelay"
                  | "maxretry"
+                 | "nowait"
                  | "retrydelay"
                  | "pollinterval"
                  | "synchronous"
                  | "user"
+                 | "group"
+                 | "debug_min"
+
+(* This expression did involve a lot of courtship around the parser *)
+let ups_fields_re = /(default|override)\.[^:=#\r\t\n \/]+/
 
 let ups_fields   = "driver"
                  | "port"
@@ -47,9 +54,12 @@ let ups_fields   = "driver"
                  | "ignorelb"
                  | "maxstartdelay"
                  | "synchronous"
+                 | "user"
+                 | "group"
+                 | "debug_min"
 @SPECIFIC_DRV_VARS@
 
-let ups_entry    = IniFile.indented_entry (ups_global|ups_fields) ups_sep ups_comment
+let ups_entry    = IniFile.indented_entry (ups_global|ups_fields|ups_fields_re) ups_sep ups_comment
 
 let ups_title    = IniFile.indented_title IniFile.record_re
 
diff --git a/scripts/augeas/nutupsdconf.aug.in b/scripts/augeas/nutupsdconf.aug.in
index 09924cfe94..24a0084c51 100644
--- a/scripts/augeas/nutupsdconf.aug.in
+++ b/scripts/augeas/nutupsdconf.aug.in
@@ -4,7 +4,8 @@ Module: NutUpsdConf
 
 Author: Raphael Pinson <raphink@gmail.com>
         Frederic Bohe  <fredericbohe@eaton.com>
-        Arnaud Quette <arnaud.quette@gmail.com>
+        Arnaud Quette  <arnaud.quette@gmail.com>
+        Jim Klimov     <jimklimov+nut@gmail.com>
 
 About: License
   This file is licensed under the GPL.
@@ -37,24 +38,36 @@ let word     = /[^"#; \t\n]+/
 let empty    = Util.empty
 let comment  = Util.comment
 let path     = word
+(* TOTHINK: What if we have spaces? Is "word" good? *)
+let certname = word
+let dbpass   = word
 
+let upsd_debug_min = [ opt_spc . key "DEBUG_MIN" . sep_spc . store num  . eol ]
 let upsd_maxage    = [ opt_spc . key "MAXAGE"    . sep_spc . store num  . eol ]
 let upsd_trackingdelay = [ opt_spc . key "TRACKINGDELAY"    . sep_spc . store num  . eol ]
 let upsd_allow_no_device = [ opt_spc . key "ALLOW_NO_DEVICE"    . sep_spc . store num  . eol ]
 let upsd_allow_not_all_listeners = [ opt_spc . key "ALLOW_NOT_ALL_LISTENERS"    . sep_spc . store num  . eol ]
+let upsd_disable_weak_ssl = [ opt_spc . key "DISABLE_WEAK_SSL"    . sep_spc . store num  . eol ]
 let upsd_statepath = [ opt_spc . key "STATEPATH" . sep_spc . store path . eol ]
 let upsd_listen    = [ opt_spc . key "LISTEN"    . sep_spc 
                           . [ label "interface" . store ip ]
                           . [ sep_spc . label "port" . store num]? ]
 let upsd_listen_list = upsd_listen . eol 
-let upsd_maxconn  = [ opt_spc . key "MAXCONN"    . sep_spc . store num  . eol ]
+let upsd_maxconn  = [ opt_spc . key "MAXCONN"  . sep_spc . store num  . eol ]
 let upsd_certfile = [ opt_spc . key "CERTFILE" . sep_spc . store path . eol ]
+let upsd_certpath = [ opt_spc . key "CERTPATH" . sep_spc . store path . eol ]
+let upsd_certident = [ opt_spc . key "CERTIDENT" . sep_spc
+                          . [ label "certname" . store certname ]
+                          . [ sep_spc . label "dbpass" . store dbpass ] . eol ]
+let upsd_certrequest = [ opt_spc . key "CERTREQUEST"    . sep_spc . store num  . eol ]
 
 (************************************************************************
+ * DEBUG_MIN level
  * MAXAGE seconds
  * TRACKINGDELAY seconds
  * ALLOW_NO_DEVICE Boolean
  * ALLOW_NOT_ALL_LISTENERS Boolean
+ * DISABLE_WEAK_SSL Boolean
  * STATEPATH path
  * LISTEN interface port
  *    Multiple lines each with one LISTEN address (or host name) and an optional
@@ -65,9 +78,23 @@ let upsd_certfile = [ opt_spc . key "CERTFILE" . sep_spc . store path . eol ]
  *    LISTEN 192.168.50.1
  *    LISTEN ::1
  *    LISTEN 2001:0db8:1234:08d3:1319:8a2e:0370:7344
+ * MAXCONN count
+ * CERTFILE path
+ *    Single certificate file (SSL with OpenSSL)
+ * CERTPATH path
+ *    Path to certificate database split into 3 files (SSL with NSS)
+ * CERTIDENT certname dbpass
+ *    Certificate identity to use by the server, and database password
+ *    as needed to read it (SSL with NSS)
+ * CERTREQUEST level
+ *    Request or require client cert? (SSL with NSS)
+ *    Possible values are :
+ *    - 0 to not request to clients to provide any certificate
+ *    - 1 to require to all clients a certificate
+ *    - 2 to require to all clients a valid certificate
  *
  *************************************************************************)
-let upsd_other  =  upsd_maxage | upsd_trackingdelay | upsd_allow_no_device | upsd_allow_not_all_listeners | upsd_statepath | upsd_listen_list | upsd_maxconn | upsd_certfile
+let upsd_other  =  upsd_debug_min | upsd_maxage | upsd_trackingdelay | upsd_allow_no_device | upsd_allow_not_all_listeners | upsd_disable_weak_ssl | upsd_statepath | upsd_listen_list | upsd_maxconn | upsd_certfile | upsd_certpath | upsd_certident | upsd_certrequest
 
 let upsd_lns    = (upsd_other|comment|empty)*
 
diff --git a/scripts/augeas/nutupsdusers.aug.in b/scripts/augeas/nutupsdusers.aug.in
index a138b61e43..92c98375f2 100644
--- a/scripts/augeas/nutupsdusers.aug.in
+++ b/scripts/augeas/nutupsdusers.aug.in
@@ -4,6 +4,7 @@ Module: NutUpsdUsers
 
 Author: Raphael Pinson <raphink@gmail.com>
         Frederic Bohe  <fredericbohe@eaton.com>
+        Jim Klimov     <jimklimov+nut@gmail.com>
 
 About: License
   This file is licensed under the GPL.
@@ -65,9 +66,11 @@ let upsd_users_instcmds   = [ del_spc
                                . ( sep_spc . upsd_users_instcmds_entry )* 
                                . ( upsd_users_comment|eol ) ]
 
+let upsd_users_upsmon_type_re     = /(master|primary|slave|secondary)/
+
 let upsd_users_upsmon    = [ del_spc
                                . key "upsmon" . sep_spc
-                               . store /master|primary|slave|secondary/ . eol ]
+                               . store upsd_users_upsmon_type_re . eol ]
 
 let upsd_users_title    = IniFile.indented_title IniFile.record_re
 
diff --git a/scripts/augeas/nutupsmonconf.aug.in b/scripts/augeas/nutupsmonconf.aug.in
index 712d81e520..f038a3ce75 100644
--- a/scripts/augeas/nutupsmonconf.aug.in
+++ b/scripts/augeas/nutupsmonconf.aug.in
@@ -4,6 +4,7 @@ Module: NutUpsmonConf
 
 Author: Raphael Pinson <raphink@gmail.com>
         Frederic Bohe  <fredericbohe@eaton.com>
+        Jim Klimov     <jimklimov+nut@gmail.com>
 
 About: License
   This file is licensed under the GPL.
@@ -31,6 +32,9 @@ let del_spc  = Util.del_opt_ws ""
 let sep_spc  = Util.del_ws_spc
 let eol      = Util.eol
 let num      = /[0-9]+/
+let num_signed = /[+-]?[0-9]+/
+let bool      = /([01]|yes|no|true|false|on|off|ok)/
+let num_bool  = /([0-9]+|yes|no|true|false|on|off|ok)/
 let word     = /[^"#; \t\n]+/
 let empty    = Util.empty
 let comment  = Util.comment
@@ -42,6 +46,8 @@ let quoted_string = del "\"" "\"" . store /[^"\n]+/ . del "\"" "\""
  * There might be a cleaner way to write this
  *  but I'm stuck with (hostname | hostname . port)?
  *)
+(* Disregard named ports, we use numbers *)
+let hostspec   = /([^ \t\n:]+|[^ \t\n:]+:[0-9]+)/
 let hostname   = [ label "hostname" . store /[^ \t\n:]+/ ]
 let port       = [ label "port"     . store num ]
 let identifier = [ label "upsname" . store /[^ \t\n@]+/ ]
@@ -59,27 +65,48 @@ let upsmon_num_re = "DEADTIME"
                   | "POLLFREQALERT"
                   | "RBWARNTIME"
 
+let upsmon_num_signed_re = "DEBUG_MIN"
+                  | "POLLFAIL_LOG_THROTTLE_MAX"
+                  | "OFFDURATION"
+                  | "OBLBDURATION"
+
+let upsmon_num_bool_re = "SHUTDOWNEXIT"
+
+let upsmon_bool_re = "CERTVERIFY"
+                  | "FORCESSL"
+
 let upsmon_num    = [ del_spc . key upsmon_num_re . sep_spc . store num . eol ]
 
+let upsmon_num_signed    = [ del_spc . key upsmon_num_signed_re . sep_spc . store num_signed . eol ]
+
+let upsmon_num_bool      = [ del_spc . key upsmon_num_bool_re . sep_spc . store num_bool . eol ]
+
+let upsmon_bool          = [ del_spc . key upsmon_bool_re . sep_spc . store bool . eol ]
+
 let upsmon_word   = [ del_spc . key "RUN_AS_USER" . sep_spc . store word . eol ]
 
 let upsmon_file_re = "NOTIFYCMD"
                   | "POWERDOWNFLAG"
                   | "SHUTDOWNCMD"
+                  | "CERTFILE"
+                  | "CERTPATH"
 
 let sto_to_eol = IniFile.sto_to_eol
-(* here we should support both quoted and not quotted
+(* here we should support both quoted and not quoted
  * string but I can't manage to find the right way of doing this
  *)
 let upsmon_file   = [ del_spc . key upsmon_file_re . sto_to_eol . eol ]
 
 (* MONITOR system powervalue username password type *)
+let upsmon_monitor_type_re     = /(master|primary|slave|secondary)/
+
+(* TOTHINK: What if we have spaces? Is "word" good? *)
 let upsmon_monitor = [ del_spc . key "MONITOR" . sep_spc
                          . [ label "system"     . identifier ] . sep_spc
                          . [ label "powervalue" . store num  ] . sep_spc
                          . [ label "username"   . store word ] . sep_spc
                          . [ label "password"   . store word ] . sep_spc
-                         . [ label "type"       . store word ] . eol  ]
+                         . [ label "type"       . store upsmon_monitor_type_re ] . eol  ]
 
 let upsmon_notify_type = "ONLINE"
 			| "ONBATT"
@@ -96,12 +123,14 @@ let upsmon_notify_type = "ONLINE"
 			| "NOTOFF"
 			| "BYPASS"
 			| "NOTBYPASS"
+			| "SUSPEND_STARTING"
+			| "SUSPEND_FINISHED"
 
 let upsmon_notify = [ del_spc . key "NOTIFYMSG" . sep_spc
                          . [ label "type" . store upsmon_notify_type . sep_spc ]
                          . [ label "message" . quoted_string ] . eol ]
 
- let flags = "IGNORE"
+let flags = "IGNORE"
 		| "SYSLOG"
 		| "WALL"
 		| "EXEC"
@@ -117,7 +146,23 @@ let upsmon_notify_flag = [ counter "record"
 			. [ label "type" . store upsmon_notify_type . sep_spc ]
 			. record+ . eol ]
 
-let upsmon_record = upsmon_num|upsmon_word|upsmon_file|upsmon_monitor|upsmon_notify|upsmon_notify_flag
+(* TOTHINK: What if we have spaces? Is "word" good? *)
+let certname = word
+let dbpass   = word
+let upsmon_certident = [ del_spc . key "CERTIDENT" . sep_spc
+                          . [ label "certname" . store certname ]
+                          . [ sep_spc . label "dbpass" . store dbpass ] . eol ]
+
+(* we can have an array of these *)
+let upsmon_certhost = [ del_spc . key "CERTHOST" . sep_spc
+                          . [ label "hostspec" . store hostspec ]
+                          . [ sep_spc . label "certname" . store certname ]
+                          . [ sep_spc . label "certverify" . store num_bool ]
+                          . [ sep_spc . label "forcessl" . store num_bool ] . eol ]
+
+let upsmon_certhost_list = upsmon_certhost . eol
+
+let upsmon_record = upsmon_num|upsmon_num_signed|upsmon_num_bool|upsmon_bool|upsmon_word|upsmon_file|upsmon_monitor|upsmon_notify|upsmon_notify_flag|upsmon_certident|upsmon_certhost_list
 
 let upsmon_lns    = (upsmon_record|comment|empty)*
 
diff --git a/scripts/augeas/tests/test_nut.aug b/scripts/augeas/tests/test_nut.aug
index 084fd8494e..186d904a65 100644
--- a/scripts/augeas/tests/test_nut.aug
+++ b/scripts/augeas/tests/test_nut.aug
@@ -10,19 +10,75 @@ test NutNutConf.nut_lns get nut_conf =
 	{ }
 	{ "MODE" = "standalone" }
 
-let ups_conf  = "
+(* desc is a single token made of two words below *)
+let ups_conf1 = "
 [testups]
 	driver = dummy-ups
 	port = auto
-	desc = \"Dummy UPS\"
+	desc = \"Dummy UPS Driver\"
 "
 
-test NutUpsConf.ups_lns get ups_conf = 
+test NutUpsConf.ups_lns get ups_conf1 =
 	{ }
-	{ "testups" 
+	{ "testups"
 		{ "driver" = "dummy-ups"   }
 		{ "port"   = "auto" }
-		{ "desc"   = "\"Dummy UPS\""    } }
+		{ "desc"   = "Dummy UPS Driver"    } }
+
+(* desc is a single token made of two words prefixed by one quote
+ * as part of its content below (escaped by backslashes) *)
+let ups_conf2 = "
+[testups]
+	driver = dummy-ups
+	port = auto
+	desc = \"\\\"Dummy UPS\" # comment line
+"
+
+test NutUpsConf.ups_lns get ups_conf2 =
+	{ }
+	{ "testups"
+		{ "driver" = "dummy-ups"   }
+		{ "port"   = "auto" }
+		{ "desc"   = "\\\"Dummy UPS"
+			{ "#comment" = "comment line" }
+		}
+	}
+
+(* desc is a single token made of two words surrounded by quotes
+ * as part of its content below (escaped by backslashes) *)
+(* FIXME: Lens fails to parse the second escaped slash, probably
+ *        because of "to_comment_re" or "entry_generic_nocomment"
+ *        test below is truncated so far:
+ * ./tests/test_nut.aug:53.0-58.41:exception thrown in test
+ * ./tests/test_nut.aug:53.5-.37:exception: Get did not match entire input
+ *     Lens: /usr/share/augeas/lenses/dist/inifile.aug:497.25-.43:
+ *     Error encountered at 5:0 (44 characters into string)
+ *     <er = dummy-ups\n\tport = auto\n|=|\tdesc = "\"Dummy UPS\""\n>
+ *
+ *     Tree generated so far:
+ *     /testups
+ * /testups/driver = "dummy-ups"
+ * /testups/port = "auto"
+ *
+ * NOTE That for NUT parsing, such trailing slash is likely a problem
+ * that is not caught by lens parser either: it should mean escaping
+ * the next character (quote) and so an unfinished line. This test case
+ * should have failed but currently does not.
+ *)
+let ups_conf3 = "
+[testups]
+	driver = dummy-ups
+	port = auto
+	desc = \"\\\"Dummy UPS\\\"
+"
+
+test NutUpsConf.ups_lns get ups_conf3 =
+	{ }
+	{ "testups"
+		{ "driver" = "dummy-ups"   }
+		{ "port"   = "auto" }
+		{ "desc"   = "\\\"Dummy UPS\\"    } }
+
 
 
 let upsd_conf = "
diff --git a/scripts/augeas/tests/test_nut_fixme.aug b/scripts/augeas/tests/test_nut_fixme.aug
new file mode 100644
index 0000000000..dc3fc0a458
--- /dev/null
+++ b/scripts/augeas/tests/test_nut_fixme.aug
@@ -0,0 +1,50 @@
+(* Tests for the Nut module *)
+(* FIXME: More development is needed in NUT lens definitions for corner cases
+ * e.g. with multiple quote characters in a line, whether escaped or not.
+ * :; ./gen-nutupsconf-aug.py ; make ; augparse --trace -I ./ ./tests/test_nut_fixme.aug && echo PASSED
+ *)
+
+module Test_nut_fixme =
+
+(* desc is a single token made of two words surrounded by quotes
+ * as part of its content below (escaped by backslashes - literally
+ * a "backslash-doublequote-Dummy-doublequote-backslash" spelling)
+ *)
+let ups_conf3 = "
+[testups]
+	driver = dummy-ups
+	port = auto
+	desc = \"A \\\"Dummy\\\" UPS\"
+"
+
+test NutUpsConf.ups_lns get ups_conf3 =
+	{ }
+	{ "testups"
+		{ "driver" = "dummy-ups"   }
+		{ "port"   = "auto" }
+		{ "desc"   = "A \\\"Dummy\\\" UPS"    } }
+
+
+
+let upsd_conf = "
+MAXAGE 30
+TRACKINGDELAY 600
+ALLOW_NO_DEVICE 1
+LISTEN 0.0.0.0 3493
+MAXCONN 1024
+CERTIDENT \"My Server Cert\" \"Db Pass Phr@se\"
+"
+
+test NutUpsdConf.upsd_lns get upsd_conf = 
+	{ }
+	{ "MAXAGE"      = "30" }
+	{ "TRACKINGDELAY" = "600" }
+	{ "ALLOW_NO_DEVICE" = "1" }
+	{ "LISTEN"
+		{ "interface" = "0.0.0.0" }
+		{ "port"     = "3493"     } }
+	{ "MAXCONN"      = "1024" }
+	{ "CERTIDENT"
+		{ "certname"   = "My Server Cert" }
+		{ "dbpass"     = "Db Pass Phr@se" } }
+
diff --git a/scripts/augeas/tests/test_nut_flaky.aug b/scripts/augeas/tests/test_nut_flaky.aug
new file mode 100644
index 0000000000..697fcd3d32
--- /dev/null
+++ b/scripts/augeas/tests/test_nut_flaky.aug
@@ -0,0 +1,27 @@
+(* Tests below pass on some systems and/or augeas versions and fail on others.
+ * Sometimes it involves same formal release with different packaging.
+ * For peace of mind, these are not currently added to common "test_nut"
+ * which is expected to pass everywhere.
+ *)
+
+module Test_nut_flaky =
+
+(* desc is a single token made of two words below
+ * encountering the "default..." line seems troublesome
+ * for some versions of augtools regardless of line position
+ *)
+let ups_conf1 = "
+[testups]
+	driver = dummy-ups
+	port = auto
+	desc = \"Dummy UPS Driver\"
+	default.battery.voltage.high = 28.8
+"
+
+test NutUpsConf.ups_lns get ups_conf1 =
+	{ }
+	{ "testups"
+		{ "driver" = "dummy-ups"   }
+		{ "port"   = "auto" }
+		{ "desc"   = "Dummy UPS Driver"    }
+		{ "default.battery.voltage.high" = "28.8" } }
diff --git a/scripts/devd/Makefile.am b/scripts/devd/Makefile.am
index e3a9967c2b..b9d9401ad3 100644
--- a/scripts/devd/Makefile.am
+++ b/scripts/devd/Makefile.am
@@ -36,7 +36,7 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/fuse/README.adoc b/scripts/fuse/README.adoc
new file mode 100644
index 0000000000..46e57e1008
--- /dev/null
+++ b/scripts/fuse/README.adoc
@@ -0,0 +1,130 @@
+NUT access via FUSE
+===================
+
+After a discussion with friends about the
+link:https://en.wikipedia.org/wiki/Filesystem_in_Userspace[FUSE] technology
+an idea resurfaced, to have NUT readings available as filesystem objects.
+
+Previously this was vaguely envisioned as a sort of `/dev/shm` on Linux or
+equivalent on other OSes (where SHM is available with a filesystem API).
+But FUSE being more portable, it is actually a better bet for this approach.
+
+* https://github.com/networkupstools/nut/issues/2591
+
+NUT access via execfuse
+~~~~~~~~~~~~~~~~~~~~~~~
+
+For a proof-of-concept, the link:https://github.com/vi/execfuse[execfuse]
+seemed appropriate. It is a daemon which knows to call user-provided programs
+to handle certain filesystem API requests. Essentially, shell scripts exposed
+as a file system!
+
+Sure, it is not very efficient or perhaps even secure, but for quick and dirty
+experiments it proved to be great! Relatively easy to debug the new code by
+saving log files, and quick to iterate by editing the shell scripts (no need
+to rebuild and restart a daemon).
+
+Installation:
+
+* Get pre-requisites to build FUSE clients, e.g. `apt install libfuse-dev`
+  on Debian-like systems, or `brew install --cask macfuse@dev` on MacOS with
+  Homebrew community packaging.
+* Download and build the `execfuse` daemon:
+----
+:; git clone https://github.com/vi/execfuse
+:; cd execfuse
+:; make && ls -la execfuse
+----
+
+That's about it, an `execfuse` binary should appear.
+
+NOTE: Examples below assume a built NUT in `~/nut` location, and a temporary
+mount point in `/tmp/nut-fuse`.
+
+You can also prepare an enviroment using NUT Integration Tests (NIT) scripts:
+----
+:; ( cd ~/nut && DEBUG_SLEEP=600 make check-NIT ) &
+
+# ...wait a few seconds for it to say the sandbox is ready
+:; . "${HOME}/nut/tests/NIT/tmp/etc/NIT.env"
+----
+
+Before mounting the FUSE file system, you can also request to debug the PoC
+scripts:
+----
+:; NUT_DEBUG_FUSE=true
+:; export NUT_DEBUG_FUSE
+
+# After running some queries, so the log-files to watch appear:
+:; tail -F /tmp/nut-debug-fuse-*.log &
+----
+
+To run with the PoC scripts here:
+
+----
+:; mkdir -p /tmp/nut-fuse
+:; PATH="$HOME/nut/clients:$PATH" \
+   ./execfuse "$HOME/nut/scripts/fuse/execfuse-nut" /tmp/nut-fuse
+----
+
+Then as you walk the `/tmp/nut-fuse` location, you would see a sub-directory
+called `by-server` under which a `localhost:3493` is exposed and any token
+(even if not visible) can be accessed with the naive assumption that it is
+a hostname/IP address and an optional port.
+
+Either way, this token is also treated as a directory, assuming it is a
+device name known to the data server `upsd` on that host. In fact, this
+directory would be populated by `upsc -l` of that host(:port) automatically.
+
+Each device represented this way is also a "directory", with "files" in it
+populated by `upsc` queries to list the currently known variables, and file
+contents populated by `upsc` queries for that variable name at that device
+on that server.
+
+Example data walk:
+
+----
+:; grep -rH /tmp/nut-fuse/localhost/dummy
+/tmp/nut-fuse/localhost/dummy/battery.charge:100
+/tmp/nut-fuse/localhost/dummy/battery.charge.low:20
+/tmp/nut-fuse/localhost/dummy/battery.runtime:1456
+/tmp/nut-fuse/localhost/dummy/battery.type:PbAc
+...
+----
+
+As another experiment, a root-directory pseudo-file was added to reveal
+the `upsc` client location and version used in the queries, just for kicks:
+
+----
+:; ls -la /tmp/nut-fuse
+total 23
+drwxr-xr-x  16 root root  4096 Jan  1  1970 .
+drwxrwxrwt 154 root root 20480 Aug 13 23:55 ..
+drwxr-xr-x  16 root root  4096 Jan  1  1970 by-server
+-r--r--r--   1 root root     0 Jan  1  1970 client-location
+-r--r--r--   1 root root     0 Jan  1  1970 client-version
+
+:; cat /tmp/nut-fuse/client-location
+/home/abuild/nut/clients/upsc
+
+:; cat /tmp/nut-fuse/client-version
+Network UPS Tools upsc 2.8.2.901.2-903-g533aa7eaf (development iteration after 2.8.2)
+----
+
+Eventually, to stop this experiment:
+
+----
+:; fusermount -u /tmp/nut-fuse
+
+# Or if user-land programs are missing, like in "macfuse@dev", just `umount`:
+:; umount /tmp/nut-fuse
+----
+
+As far as a PoC goes, this is already a fun and quickly achieved result,
+although for production use something like a FUSE-capable `upsmon`-like
+client would be needed both for efficiency (to avoid dozens of process
+forks and networked queries to get each reading), and to deal with security
+somehow (for a shot at `upsrw` and `upscmd` equivalents).
+
+Hope this helps get the real development going,
+Jim Klimov
diff --git a/scripts/fuse/execfuse-nut/getattr b/scripts/fuse/execfuse-nut/getattr
new file mode 100755
index 0000000000..6a13a013a5
--- /dev/null
+++ b/scripts/fuse/execfuse-nut/getattr
@@ -0,0 +1,51 @@
+#!/bin/bash
+
+# Simple PoC of NUT client as a FUSE mountable filesystem
+# Requires https://github.com/vi/execfuse
+# Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+# Licensed GPLv2+ as NUT codebase
+
+if [ x"$NUT_DEBUG_FUSE" = xtrue ] ; then
+    exec 2>"/tmp/nut-debug-fuse-`basename $0`.log"
+    echo "ARGS($#, $0): 1='$1' 2='$2' @='$@'" >&2
+fi
+
+D=""
+F=""
+case "$1" in
+    /|/by-server)
+        D="$1"
+        ;;
+    /by-server/*/*/*/*) # Don't want subdirs here
+        ;;
+    /by-server/*/*/*)
+        # VARNAME
+        F="`basename "$1"`"
+        # UPSSRV/UPSNAME
+        D="`echo "$1" | sed 's,^/by-server/\(.*\)/'"$F"'$,\1,'`"
+        ;;
+    /by-server/*/*)
+        # UPSSRV/UPSNAME
+        D="`echo "$1" | sed 's,^/by-server/\(.*\)$,\1,'`"
+        ;;
+    /by-server/*) # No further slash
+        # UPSSRV
+        D="`basename "$1"`"
+        ;;
+    /client-location|/client-version)
+        F="$1"
+        ;;
+    *)
+        ;;
+esac
+
+if [ -n "$F" ] ; then
+    printf 'ino=1 mode=-r--r--r-- nlink=1 uid=0 gid=0 rdev=0 size=0 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 %s\0' "$1"
+else
+    if [ -n "$D" ] ; then
+        printf 'ino=1 mode=drwxr-xr-x nlink=16 uid=0 gid=0 rdev=0 size=4096 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 %s\0' "$1"
+    else
+        exit 1
+    fi
+fi
+
diff --git a/scripts/fuse/execfuse-nut/init b/scripts/fuse/execfuse-nut/init
new file mode 100755
index 0000000000..1a2485251c
--- /dev/null
+++ b/scripts/fuse/execfuse-nut/init
@@ -0,0 +1 @@
+#!/bin/sh
diff --git a/scripts/fuse/execfuse-nut/read_file b/scripts/fuse/execfuse-nut/read_file
new file mode 100755
index 0000000000..22300d92f5
--- /dev/null
+++ b/scripts/fuse/execfuse-nut/read_file
@@ -0,0 +1,43 @@
+#!/bin/bash
+
+# Simple PoC of NUT client as a FUSE mountable filesystem
+# Requires https://github.com/vi/execfuse
+# Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+# Licensed GPLv2+ as NUT codebase
+
+if [ x"$NUT_DEBUG_FUSE" = xtrue ] ; then
+    exec 2>"/tmp/nut-debug-fuse-`basename $0`.log"
+    echo "ARGS($#, $0): 1='$1' 2='$2' @='$@'" >&2
+fi
+
+#PATH="~/nut/clients:$PATH"
+#export PATH
+
+case "$1" in
+    /by-server/*/*/*/*) # Don't want subdirs here
+        ;;
+    /by-server/*/*/*)
+        VARNAME="`basename "$1"`"
+        UPS="`echo "$1" | sed 's,^/by-server/\([^/]*\)/\([^/]*\)/'"$VARNAME"'$,\2@\1,'`"
+        if [ x"$NUT_DEBUG_FUSE" = xtrue ] ; then
+            #echo "+upsc '$UPS' '$VARNAME'" >&2
+            set -x
+        fi
+        upsc "$UPS" "$VARNAME"
+        exit $?
+        ;;
+    /client-location)
+        command -v upsc
+        exit $?
+        ;;
+    /client-version)
+        if [ x"$NUT_DEBUG_FUSE" = xtrue ] ; then
+            #echo "+upsc '$UPS' '$VARNAME'" >&2
+            set -x
+        fi
+        NUT_DEBUG_LEVEL=6 upsc -V
+        exit $?
+        ;;
+esac
+
+exit 1
diff --git a/scripts/fuse/execfuse-nut/readdir b/scripts/fuse/execfuse-nut/readdir
new file mode 100755
index 0000000000..27f13696b0
--- /dev/null
+++ b/scripts/fuse/execfuse-nut/readdir
@@ -0,0 +1,70 @@
+#!/bin/bash
+
+# Simple PoC of NUT client as a FUSE mountable filesystem
+# Requires https://github.com/vi/execfuse
+# Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+# Licensed GPLv2+ as NUT codebase
+
+if [ x"$NUT_DEBUG_FUSE" = xtrue ] ; then
+    exec 2>"/tmp/nut-debug-fuse-`basename $0`.log"
+    echo "ARGS($#, $0): 1='$1' 2='$2' @='$@'" >&2
+    #echo "ARGS: $#: $@" >&2
+    #set | grep -E '^[^ =]*=' >&2
+fi
+
+#PATH="~/nut/clients:$PATH"
+#export PATH
+
+#exec find "$2$1" -mindepth 1 -maxdepth 1 -printf 'ino=%i mode=%M nlink=%n uid=%U gid=%G rdev=0 size=%s blksize=512 blocks=%b atime=%A@ mtime=%T@ ctime=%C@ %f\0'
+
+# $1 = (parent?) dirname
+# $2 = dir basename?
+
+print_dots() {
+    printf 'ino=1 mode=drwxr-xr-x nlink=4 uid=0 gid=0 rdev=0 size=4096 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 .\0'
+    printf 'ino=1 mode=drwxr-xr-x nlink=4 uid=0 gid=0 rdev=0 size=1111 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 ..\0'
+}
+
+case "$1" in
+    /)
+        print_dots
+        for D in "by-server" ; do
+            printf 'ino=1 mode=drwxr-xr-x nlink=4 uid=0 gid=0 rdev=0 size=4096 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 %s\0' "$D"
+        done
+        for F in "client-location" "client-version" ; do
+            printf 'ino=1 mode=-r--r--r-- nlink=1 uid=0 gid=0 rdev=0 size=4096 blksize=512 blocks=2 atime=0 mtime=0 ctime=0 %s\0' "$F"
+        done
+        ;;
+    /by-server)
+        print_dots
+        printf 'ino=1 mode=drwxr-xr-x nlink=16 uid=0 gid=0 rdev=0 size=16 blksize=512 blocks=1 atime=0 mtime=0 ctime=0 %s\0' "localhost"
+        # Primarily this is a value arranged by `make check-NIT`:
+        set -x
+        if [ -n "${NUT_PORT-}" ] && [ x"${NUT_PORT}" != x3493 ]; then
+            printf 'ino=1 mode=drwxr-xr-x nlink=16 uid=0 gid=0 rdev=0 size=16 blksize=512 blocks=1 atime=0 mtime=0 ctime=0 %s\0' "localhost:${NUT_PORT}"
+        fi
+        ;;
+    /by-server/*/*/*) # Don't want subdirs here
+        exit 2 # ENOENT
+        ;;
+    /by-server/*/*) # list device variables
+        UPSNAME="`basename "$1"`"
+        UPSSRV="`echo "$1" | sed 's,^/by-server/\(.*\)/'"$UPSNAME"'$,\1,'`"
+        print_dots
+        for VARNAME in `upsc "$UPSNAME@$UPSSRV" | awk -F: '{print $1}'` ; do
+            printf 'ino=1 mode=-r--r--r-- nlink=1 uid=0 gid=0 rdev=0 size=16 blksize=512 blocks=1 atime=0 mtime=0 ctime=0 %s\0' "$VARNAME"
+        done
+        ;;
+    /by-server/*) # devices on hostname
+        UPSSRV="`basename "$1"`"
+        print_dots
+        for UPSNAME in `upsc -l "$UPSSRV"` ; do
+            printf 'ino=1 mode=drwxr-xr-x nlink=16 uid=0 gid=0 rdev=0 size=16 blksize=512 blocks=1 atime=0 mtime=0 ctime=0 %s\0' "$UPSNAME"
+        done
+        ;;
+    *)
+        exit 2 # ENOENT
+        ;;
+esac
+
+exit 0
diff --git a/scripts/hotplug/Makefile.am b/scripts/hotplug/Makefile.am
index 8888492885..5fa7809f86 100644
--- a/scripts/hotplug/Makefile.am
+++ b/scripts/hotplug/Makefile.am
@@ -28,7 +28,7 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/installer/.gitignore b/scripts/installer/.gitignore
new file mode 100644
index 0000000000..3675763f29
--- /dev/null
+++ b/scripts/installer/.gitignore
@@ -0,0 +1 @@
+/common_EN/license.txt
diff --git a/scripts/installer/Makefile.am b/scripts/installer/Makefile.am
index ae236cf88b..134ba00ecd 100644
--- a/scripts/installer/Makefile.am
+++ b/scripts/installer/Makefile.am
@@ -30,12 +30,22 @@ EXTRA_DIST = \
 	solcmn/solaris_init	\
 	solcmn/ipp-os-shutdown.conf.sample
 
+# Originally an Eaton license was used, changed along with donation of sources
+# to NUT project. Having the file name populated helps keep the scripts as is.
+common_EN/license.txt: $(top_srcdir)/LICENSE-GPL2
+	$(MKDIR_P) '$(@D)'
+	cp -pf '$?' '$@'
+
 SPELLCHECK_SRC = README.adoc common/README_ipp-os-shutdown.adoc
 
+nut:
+	rm -f "$@"
+	$(LN_S) $(top_srcdir) "$@"
+
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
@@ -52,6 +62,10 @@ SPELLCHECK_SRC = README.adoc common/README_ipp-os-shutdown.adoc
 spellcheck spellcheck-interactive spellcheck-sortdict:
 	+$(MAKE) -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC="$(SPELLCHECK_SRC)" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
-CLEANFILES = *-spellchecked
+CLEANFILES = *-spellchecked */*-spellchecked common_EN/license.txt
+
+# Remove "nut" if it is a symlink to the source tree
+clean-local:
+	if test -L nut || test -h nut ; then rm -f nut ; fi
 
 MAINTAINERCLEANFILES = Makefile.in .dirstamp
diff --git a/scripts/installer/README.adoc b/scripts/installer/README.adoc
index 7c94a8be24..e701310599 100644
--- a/scripts/installer/README.adoc
+++ b/scripts/installer/README.adoc
@@ -8,13 +8,54 @@ of Eaton by Frederic Bohe, Vaclav Krpec, Arnaud Quette and Jim Klimov.
 
 This includes the package (tarball) creation script which relies on
 presence of third-party library binaries in a `$ARCH/libs` directory,
-and init-scripts from NUT source tree (originally expected as a "nut"
-subdirectory), as well as an interactive installer script to set up
-the package on a target deployment covering package (re-)installation,
-initial device discovery, password setup, etc., and helper scripts
-for status overview and shutdown handling.
+pre-built package files (courtesy of NUT `make package` recipes),
+and init-scripts from NUT source tree (originally expected as a `nut`
+subdirectory, can be a symlink to `../..`; currently copies stored in
+the `$ARCH` subdirectories; eventually should be taken from NUT sources
+during build, or from packages), as well as an interactive text-mode
+installer script to set up the package on a target deployment covering
+package (re-)installation, initial device discovery, password setup,
+etc., and helper scripts for status overview and shutdown handling.
 
-The installer relies on "nutconf" tool (emulating dummy script for
+Example `$ARCH` related directory layout in original posting (binary
+files mentioned below are not provided into NUT Git source code base);
+these are the contents `make_package.sh` script expects to work with
+(you can see the names mentioned in `find ... | grep -v ...` filters):
+
+* `aix/` example for AIX 6 and 7 based IPSS Unix releases:
+  * `libs/`: `libcrypto.a`, `libcrypto.so`, etc...
+  * `nut-2.6.5-1.aix6.1.ppc.rpm` and `nut-client-2.6.5-1.aix6.1.ppc.rpm`
+    package files
+  * `nutconf` binary for the platform
+  * `aix_init` script
+  * `ipp-os-shutdown.conf.sample`
+
+* `hpux/` for PA-RISC:
+  * `libs/`: `libcrypto.sl`, `libexpat.sl`, `libiconv.sl`, `libintl.sl`,
+    `libltdl.sl`, `libneon.sl`, `libnetsnmp.sl.30`, `libssl.sl`, `libz.sl`
+    * Notably, `libnutscan.sl.1` (other platforms did not carry a copy)
+  * `nut.depot.tar.gz` package file
+  * `nutconf` binary for the platform
+  * `ipp-os-shutdown.conf.sample`
+
+* Solaris (SPARC and X86) spread across 3 directories:
+  * `solcmn/` with common platform-independent files:
+    * `ipp-os-shutdown.conf.sample`
+    * `solaris_init` script
+
+  * `solari` with SPARC binaries:
+    * `libs/`: `libcrypto.so.0.9.8`, `libz.so`, etc.
+    * `NUT_solaris_sparc_package2.6.5.local` package file
+    * `nutconf` binary for the platform
+
+  * `solint` with X86 binaries:
+    * `libs/`: `libcrypto.so.1.0.0`, `libgcc_s.so.1`, `libltdl.so.7`,
+      `libneon.so.27`, `libnetsnmp.so.15`, `libproxy.so.0`,
+      `libssl.so.1.0.0`, `libstdc++.so.6`, `libwrap.so.1`
+    * `NUT_solaris_i386_package2.6.5.local` package file
+    * `nutconf` binary for the platform
+
+The installer relies on `nutconf` tool (emulating dummy script for
 tests provided here), which is part of NUT sources.
 
 Note that heavy use of `LD_LIBRARY_PATH` in these scripts may become
@@ -24,6 +65,7 @@ symbols during dynamic linking), so while this contribution here is
 published "as is", more work would be needed to make it useful in
 modern environments. Helper scripts should be quickly useful though.
 
-Developed (pre-?)2013-2018 by Eaton; contributed to NUT 2022 by Eaton
+Developed (pre-?)2013-2018 by Eaton; contributed to NUT and re-licensed
+under same terms as NUT in 2022 by Eaton.
 
 Maintained since 2024 by Jim Klimov <jimklimov+nut@gmail.com>
diff --git a/scripts/installer/common_EN/license.txt b/scripts/installer/common_EN/license.txt
deleted file mode 100644
index 2817e194c0..0000000000
--- a/scripts/installer/common_EN/license.txt
+++ /dev/null
@@ -1,636 +0,0 @@
-
-                      Eaton Corporation
-                              
-                 END-USER LICENSE AGREEMENT
-
-
-Revised: June, 2008
-
-
-IMPORTANT, READ CAREFULLY.  THIS EATON CORPORATION END  USER
-LICENSE  AGREEMENT (THE "AGREEMENT") IS A  BINDING  CONTRACT
-BETWEEN  YOU,  THE  END-USER  (THE  "LICENSEE")  AND   EATON
-CORPORATION ("EATON" OR "LICENSOR").  EXCEPT TO  THE  EXTENT
-YOU  ARE BOUND BY A WRITTEN AGREEMENT SIGNED BY BOTH YOU AND
-EATON  REGARDING  THE  USE  AND  LICENSE  OF  THIS  SOFTWARE
-PRODUCT, BY INSTALLING OR USING THIS SOFTWARE PRODUCT,  YOU,
-THE  LICENSEE,  ARE  AGREEING TO  BE  BOUND  BY  THE  TERMS,
-CONDITIONS   AND   LIMITATIONS  OF  THIS  AGREEMENT,   WHICH
-INCLUDES, BUT IS NOT LIMITED TO, THE SOFTWARE USAGE LICENSE,
-THE   DISCLAIMER  OF  WARRANTY  AND  LIMITED  WARRANTY,  AND
-LIMITATION OF EATON LIABILITY.
-
-READ  THE  TERMS AND CONDITIONS OF THIS AGREEMENT  CAREFULLY
-BEFORE  INSTALLING OR USING THE SOFTWARE.   IF  YOU  DO  NOT
-AGREE  TO  THE  TERMS,  CONDITIONS AND LIMITATIONS  OF  THIS
-AGREEMENT,  PROMPTLY  DELETE THE  LICENSE  FILE  MEDIA,  THE
-ENTIRE  MEDIA  PACKAGE AND SOFTWARE FROM YOUR  COMPUTER  AND
-RETURN THE LICENSE FILE DISKETTE(S), THE ENTIRE DISK PACKAGE
-AND  ALL OTHER ITEMS (INCLUDING DOCUMENTATION AND PACKAGING)
-WITHIN 30 DAYS OF RECEIPT OF THE SOFTWARE TO THE PLACE  FROM
-WHICH YOU OBTAINED IT FOR A FULL REFUND.
-
-EACH  EATON LICENSED PRODUCT INCORPORATES ADDITIONAL  TERMS,
-CONDITIONS, AND LIMITATIONS THAT ARE IDENTIFIED AS  EXHIBITS
-TO  THIS  AGREEMENT (SOME OR ALL OF WHICH ARE  ATTACHED  AND
-INCORPORATED   HEREIN).    NOTWITHSTANDING   THE    ATTACHED
-EXHIBITS,  LICENSOR  MAY  LICENSE  ADDITIONAL  PRODUCTS   TO
-LICENSEE  SUBJECT TO THE ADDITIONAL EXHIBITS, A  LISTING  OF
-WHICH IS AS FOLLOWS: "EXHIBIT A" APPLIES TOEATON PRODUCTS.
-
-
-
-----------------------------------
-1.0  Definitions
-----------------------------------
-
-
-1.1  Documentation.  Documentation means the user guides and
-manuals  for  the  installation and  use  of  the  Software,
-whether provided in CD-ROM, hard copy, or other form.
-
-
-
-1.2   License Fee.  License Fee means the fee paid to  Eaton
-for  each  specific  license to  use  the  Software  granted
-hereunder as may be identified in an Order Form received and
-accepted by Eaton.
-
-
-
-1.3   License File.  License File means a component  of  the
-Software  that enables one or more other components  of  the
-Software and may also specify the location of the Designated
-Device  and  the Licensee.  The License File also  specifies
-certain limitations on the use of the enabled components  of
-the  Software and the purposes for, and extent to, which the
-enabled  components of the Software may  be  used.   Certain
-components of the Software may be licensed hereunder without
-a  License File.  For reference purposes, the components  of
-the  Software enabled by a particular License File correlate
-to  Eaton  part numbers as may be reflected on  the  License
-File or on one or more Order Forms or License Certificate.
-
-
-
-1.4   Licensed  Key.  License Key means a  key  provided  to
-Licensee by Eaton to enable functionality of the Software.
-
-
-
-1.5   Order Form.  Order Form means (i) the document in hard
-or electronic copy by which particular Software or Technical
-Support Services is ordered by or for Licensee and by  which
-Eaton  is  advised of the location of the Designated  Device
-and (ii)  any order confirmation that may be issued by Eaton
-acknowledging receipt of, or accepting, an order by Licensee
-for particular Software or Technical Support Services.
-
-
-
-1.6    Software.   Software  means  the  computer   software
-programs  for which Licensee is granted a license hereunder,
-the  License  Files necessary to enable those programs,  the
-Documentation  therefore and, to the extent Licensee  either
-purchases  an  Update or is entitled to receive  Updates  in
-connection with certain Technical Support Services purchased
-pursuant  to  Section  3.2, Updates thereto.   All  computer
-programs  are  licensed hereunder in object  code  (machine-
-readable)  form only except that certain "toolkit"  software
-programs may include limited portions in source code (human-
-readable) form.
-
-
-
-1.7   Technical  Support (Maintenance) Services.   Technical
-Support  (Maintenance) Services means: (i) services provided
-to  Licensee under an Support Agreement pursuant to  Eaton's
-Support  Services  Policies, Terms and Conditions  ("Support
-Services  Policy")  in effect on the date  the  Software  is
-delivered  to Licensee or as changed from time  to  time  by
-Eaton,  and may include if available for the Eaton  Licensed
-Product  (ii) Training Services provided pursuant to Eaton's
-Training  policies in effect on the date such  services  are
-ordered by or for Licensee.
-
-
-
-1.8   Update.   Update means: (a) supplemental programs,  if
-and  when  developed  and distributed  by  Eaton,  that  may
-contain  bug  fixes  or improved program functions  for  the
-Software;  and (b) a subsequent release of the Software,  if
-and  when  developed by Eaton, which Eaton  generally  makes
-available  for licensees that have an Support Agreement  and
-to  which  Licensee is entitled under the  Support  Services
-Policy  by  virtue  of having purchased such  services.   An
-Update does not include any release, new version, option, or
-future product, which Eaton licenses separately.
-
-
-------------------------------------
-2.0  Software License
-------------------------------------
-
-
-2.1    Ownership.   Licensee  owns  the  magnetic  or  other
-physical  media  upon which the Software  is  originally  or
-subsequently recorded or fixed, but Eaton or Eaton Licensors
-retains  all  title, copyright and other proprietary  rights
-in,  and ownership of, the Software regardless of the  media
-upon  which  the  original or any copy may  be  recorded  or
-fixed.   Licensee  does not acquire any rights,  express  or
-implied,  other  than  those  expressly  granted   in   this
-Agreement.   Eaton grants to Licensee a non-exclusive,  non-
-assignable  license to use the Software in conjunction  with
-the  operation of Eaton products or other products described
-by  Eaton  in the Documentation.  Licensee will use Licensed
-Keys  provided per the limitations set forth  in  the  Order
-Form  Licensee will not, nor will Licensee suffer or  permit
-others  to,  modify,  adapt,  translate,  reverse  engineer,
-decompile,  or  disassemble the Software  or  any  component
-thereof  (including the Documentation), or create derivative
-works  based  on the Software (including the Documentation),
-except to the extent such forgoing restriction is prohibited
-by applicable law.
-
-
-
-2.2   Copy  Restrictions.  Copyright laws and  international
-treaties  protect the Software, including the Documentation.
-Unauthorized  copying of the Software, the Documentation  or
-any part thereof, is expressly prohibited.  Subject to these
-restrictions,  Licensee  may make  a  reasonable  number  of
-copies  of  the  Software  solely  for  backup  or  archival
-purposes,  and  may make a limited number of copies  of  the
-Documentation  for  use by Licensee in connection  with  its
-authorized  use of the Software.  Licensee will  number  and
-account  for  all such copies.  All titles, trademarks,  and
-copyright  and  restricted rights notices  included  in  the
-Software  and  Documentation  will  be  reproduced  in  such
-copies.
-
-
-
-2.3   Transfer  and Assignment Restrictions.  Licensee  will
-not   voluntarily  sell  or  involuntarily  assign,   lease,
-sublicense, encumber, or otherwise transfer its interest  in
-this Agreement or in the Software, or Documentation in whole
-or  in  part,  or allow any other person (except  Licensee's
-bona  fide  employees) or entity, including  any  parent  or
-subsidiary  of  Licensee or other subsidiary  of  Licensee's
-parent,  to use the Software without the written consent  of
-Eaton.   Any  dissolution, merger, consolidation,  or  other
-reorganization of Licensee, or the sale or other transfer of
-a  controlling percentage of the capital stock  of  Licensee
-shall be deemed a voluntary assignment.
-
-
-
-2.4   Verification.   At Eaton's written request,  not  more
-frequently than annually, Licensee will furnish Eaton with a
-signed  certification verifying that the Software  is  being
-used  in  accordance with the provisions of this  Agreement.
-Eaton  may audit Licensee's use of the Software.   Any  such
-audit  will  be conducted during regular business  hours  at
-Licensee's  facilities  and will not unreasonably  interfere
-with  Licensee's business activities.  If an  audit  reveals
-that  Licensee is using Software contrary to the  terms  and
-limitations of this License Agreement then Licensee will  be
-invoiced   for  additional  license  fees  consistent   with
-Licensee's  actual  use of the Software in  accordance  with
-Eaton's  then  current price list for the Software  and  the
-cost of the audit, which amount will be immediately due  and
-payable.  This assessment of additional fees will be without
-prejudice to any other remedies Eaton may have for breach of
-this  Agreement,  including without  limitation  termination
-under Section 3.2.
-
-
-------------------------------
-3.0  Termination
-------------------------------
-
-3.1   Termination by Licensee.  Licensee may  terminate  the
-license  granted  hereunder at any  time  upon  delivery  of
-written  notice  to  Eaton.  Termination  will  not  relieve
-Licensee of its obligations specified in Section 3.3 below.
-
-
-
-3.2   Termination by Eaton.  This Agreement and the  license
-granted   hereunder  automatically  terminates  if  Licensee
-breaches any provision of this Agreement including  but  not
-limited  to  the failure to pay in full the License  Fee  or
-Technical Support (Maintenance) fee when due.
-
-
-
-3.3  Effect of Termination.  Immediately upon termination of
-this  Agreement  or the license granted hereunder,  Licensee
-will  cease  using the Software, will delete  the  Software,
-including the License File(s), from its computers  and  will
-either  return  to Eaton or destroy the Software,  including
-the License File(s), Documentation, packaging and all copies
-thereof.   If  Licensee elects to destroy the Software  then
-Licensee will certify in writing to Eaton the destruction of
-the  Software.  Termination of this Agreement and return  or
-destruction of the Software will not limit either party from
-pursuing   other   remedies  available  to   it,   including
-injunctive   relief,  nor  will  such  termination   relieve
-Licensee's obligation to pay all fees and expenses that have
-accrued  or  are  otherwise  owed  by  Licensee  under  this
-Agreement or any Order Form received and accepted by  Eaton.
-The  parties'  rights  and obligations under  the  following
-sections of this Agreement will survive termination of  this
-Agreement:   Article 1.0, Article 2.1, Section 2.2,  Section
-2.3, Section 2.4 Article 3.0, Article 4.0 and Article 5.0.
-
-
-
-------------------------------------------------------------
-4.0  Infringement, Indemnity and Remedies
-------------------------------------------------------------
-
-
-4.1  Infringement Indemnity.  Subject to the limitations  in
-Articles  4  and 5 of this Agreement, Eaton will defend  and
-indemnify   Licensee  against  a  third  party   claim   (an
-"Indemnified Claim") that the Software infringes any  patent
-and/or copyright enforceable in the United States of America
-or   misappropriates  any  trade  secret   (as   the   terms
-"misappropriation"  and "trade secret" are  defined  in  the
-Uniform Trade Secrets Act) protected under the laws  of  any
-of  the  United States, provided that: (i) Licensee notifies
-Eaton in writing within 30 days of the claim; (ii) Eaton has
-sole  control  of  the  defense and all  related  settlement
-negotiations;  and (iii) Licensee provides  Eaton  with  the
-assistance, information and authority necessary  to  perform
-Eaton's   obligations   under   this   Section.    For   any
-intellectual  property  claim for which  a  defense  is  not
-provided in this Section 4.1, Eaton, in its sole discretion,
-may  elect to treat such intellectual property claim  as  an
-Indemnified  Claim  as defined in this Section  4.1.   Eaton
-will  have no liability for any claim of infringement  based
-on use of a superseded or altered release of Software if the
-infringement would have been avoided by the use of a current
-unaltered  release of the Software which was  obtainable  by
-Licensee from Eaton.
-
-Eaton  will  have  no  obligation to any  Licensee  for  any
-Indemnified  Claims  relating to  allegations  of  copyright
-infringement which arise outside the geographical boundaries
-of  the United States, Canada, Japan, or the European  Union
-("Included   Jurisdictions"),  or  any  Indemnified   Claims
-relating  to  allegations  of trade secret  misappropriation
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-
-----------------------------------------
-5.0  General Provisions
-----------------------------------------
-
-
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-obligation  to, create Updates of the Software or components
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-5.3   Notices.   All notices required to be  sent  hereunder
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-5.4   Severability.  If any provision of this  Agreement  is
-held   to   be  invalid  or  unenforceable,  the   remaining
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-5.5   Waiver.  The waiver by either party of any default  or
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-5.6   Entire Agreement.  This Agreement (together  with  any
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-Order  Form  or  other  purchasing  document  submitted   by
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-will  be  supplemental hereto to the extent not inconsistent
-herewith.   If a copy of this Agreement in a language  other
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-it  is  included  for convenience and the  English  language
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-5.7   Heirs, Successors, and Assigns.  Each and all  of  the
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-will be binding upon and inure to the benefit of the parties
-hereto and, to the extent permitted by this Agreement, their
-respective  heirs,  legal  representatives,  successors  and
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-
-5.8   Export Restrictions.  Licensee agrees to comply  fully
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-Software  nor  any direct product thereof are (I)  exported,
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-are  intended to be used for any purposes prohibited by  the
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-goods  or  services, which currently include,  but  are  not
-limited  to Cuba, Iran, Iraq, Libya, North Korea, Sudan  and
-Syria,  or  to  any  national of any such country,  wherever
-located,  who intends to transmit or transport the  Software
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-knows or has reason to know will utilize the Software in the
-design,  development or production of nuclear,  chemical  or
-biological  weapons; or (iii) to any end-user who  has  been
-prohibited from participating in U.S. export transactions by
-any federal agency of the U.S. government.
-
-
-
-5.9   U.S. Government Restricted Rights.  The Software is  a
-"commercial  item" as that term is defined at 48  CFR  2.101
-(October 1995), consisting of "commercial computer software"
-and  "commercial computer software documentation",  as  such
-terms  are  used in 48 CFR 12.212 (September 1995),  and  is
-provided  to  the U.S. Government only as a  commercial  end
-item.  Consistent with 48 CFR 12.212 and 48  CFR  227.7202-1
-through  227.7202-4  (June 1995), all  U.S.  Government  End
-Users  acquire the Software with only those rights set forth
-herein. Contractor/ manufacturer is Eaton Corporation,  8609
-Six Forks Road, Raleigh, North Carolina 27615.
-
-
-
-5.10  Third Party Intellectual Property Right Notices.   The
-Software  may  contain components that are  owned  by  third
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-embedded  in,  the Software pursuant to license arrangements
-between  Eaton  and such third parties.  Use  of  the  Eaton
-Licensor components embedded in the Software is subject  to:
-(i)  this  Agreement  or (ii) the Eaton Licensors  end  user
-license  agreement (EULA) if provided with the  installation
-of  the  Software (a copy of which is available  from  Eaton
-upon  request).   In  addition,  License  agrees  that   the
-embedded components may not be used in any other fashion  or
-for  any  other  purpose other than as provided  under  this
-Agreement  or  the  EULA.  Copyright and  other  proprietary
-rights notices of Eaton and Eaton Licensors are contained in
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-obfuscate any such notices.
-
-
-
-5.11   Confidentiality.    The   Software,   including   the
-Documentation,  the terms and pricing under this  Agreement,
-and any other information that may be marked as confidential
-is   confidential  and  proprietary  information  of   Eaton
-("Confidential Information").  Results of any  benchmark  or
-general  performance  or  feature evaluation  tests  on  the
-Software  run  by Licensee may not be disclosed  outside  of
-Licensee's organization without the prior written consent of
-Eaton.   Licensee will hold the Confidential Information  in
-strict  confidence  during the term of  this  Agreement  and
-until  such Confidential Information falls within the public
-domain.  Licensee will take reasonable steps to ensure  that
-its  employees  and  agents  also  comply  with  the  strict
-confidentiality  obligations  of  this  Section.    Licensee
-acknowledges  that  confidential  aspects  of  the  Software
-(including any source code) is a trade secret of Eaton,  the
-disclosure  of which would cause substantial harm  to  Eaton
-that  could not be remedied by the payment of damages alone.
-Accordingly,  Eaton  will  be entitled  to  preliminary  and
-permanent  injunctive  and other equitable  relief  for  any
-breach of this Section 5.11.
-
-
-
-5.12 Note on JAVA Support.  The Software may contain support
-for  programs written in JAVA.  JAVA technology is not fault
-tolerant and is not designed, manufactured, or intended  for
-use  or  resale  as  online control equipment  in  hazardous
-environments requiring fail-safe performance, such as in the
-operation  of  nuclear  facilities, aircraft  navigation  or
-communications  systems, air traffic  control,  direct  life
-support  machines, or weapons systems, in which the  failure
-of  JAVA  technology could lead directly to death,  personal
-injury,  or severe physical or environmental damage.   EATON
-DISCLAIMS   ALL  DAMAGES  INCLUDING  DIRECT,  INDIRECT   AND
-CONSEQUENTIAL  DAMAGES  RELATING  TO  THE  FAILURE  OF   ANY
-SOFTWARE INCLUDING JAVA PROGRAMS AND/OR JAVA TECHNOLOGY.
-
-
-
-5.13  Eaton.   Through its Eaton Solution Providers  Program
-Eaton  may  make  available for licensing  from  independent
-third  party  vendors ("Program Vendors")  certain  computer
-software products ("Program Products").  Licensing  and  use
-of Program Products are subject to the terms and limitations
-of  separate  license  agreements  with  each  such  Program
-Vendor, which license agreements must be viewed and accepted
-prior   to,  or  concurrently  with,  the  down-loading   or
-installation  of  the  Program  Product.   Eaton  makes   no
-representation  or  warranty with  respect  to  any  Program
-Products.
-
-
-
-5.14 Governing Law.  This Exhibit and the Agreement will  be
-interpreted and enforced in accordance with the laws of  the
-State  of Ohio or Pennsylvania, without regard to choice  of
-law principles.
-
-
-
-5.15  Jurisdiction and Arbitration All disputes,  claims  or
-controversies arising out of or relating to this Exhibit  or
-the  Agreement  that are not resolved by the  parties'  good
-faith attempt to negotiate a resolution will be submitted to
-final and binding arbitration before JAMS/Endispute, or  its
-successor, in Norfolk County Massachusetts, USA, pursuant to
-the  United States Arbitration Act, 9 U.S.C. Sec. 1 et  seq.
-The  arbitration  will be conducted in accordance  with  the
-provisions of JAMS/Endispute's Streamlined Arbitration Rules
-and Procedures in effect at the time of filing of the demand
-for   arbitration.    The  parties   will   cooperate   with
-JAMS/Endispute  and  each  other  in  selecting   a   single
-arbitrator  who  will  be a former  judge  or  justice  with
-substantial experiences in resolving business disputes  with
-particular   experience  in  resolving  disputes   involving
-computer software.  The costs of arbitration will be  shared
-equally by the parties.  The provisions of this Section  may
-be  enforced  by  any court of competent jurisdiction.   The
-arbitrator will not be empowered to award damages in  excess
-of,   or   inconsistent  with,  the  liability   limitations
-contained  in  this Exhibit or the Agreement;  however,  the
-prevailing party will be entitled to an award of all  costs,
-fees  and  expenses,  including  expert  witness  fees   and
-attorneys  fees,  to  be  paid by  the  party  against  whom
-enforcement is ordered .
-
-
-
-Eaton Corporation EULA June, 2008
-
diff --git a/scripts/installer/make_package.sh b/scripts/installer/make_package.sh
index acccf35314..6c3aa66e81 100755
--- a/scripts/installer/make_package.sh
+++ b/scripts/installer/make_package.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #	make_package.sh
 #	Copyright (c) 2013-2015, by Eaton (R) Corporation. All rights reserved.
@@ -12,9 +12,14 @@
 rm -Rf package
 mkdir package
 
-git pull --all
+# NOTE: Originally this pulled installer sources (separate from NUT code base)
+# If this script were to be modernized, it could be prudent to `make package`
+# in NUT sources for each platform, to create the package file(s) tarballed
+# below for end-user along with the interactive installer delivery.
+#git pull --all
 # [ $? = 0 ] && git merge upstream/master || exit $?
 
+# NOTE: See README.adoc about expected subdirectory contents with binary files
 NAME="ipp-solaris-$IPP_VERSION.sparc"
 mkdir "package/$NAME"
 FILE_LIST="`find . -type f -name '*' | egrep -v '.svn|.git|./nutconf-dummy|./make_package.sh|nut/|(un|)install.log|package/|aix|hpux|solint'`"
diff --git a/scripts/installer/nut b/scripts/installer/nut
deleted file mode 120000
index c25bddb6dd..0000000000
--- a/scripts/installer/nut
+++ /dev/null
@@ -1 +0,0 @@
-../..
\ No newline at end of file
diff --git a/scripts/misc/notifyme-debug b/scripts/misc/notifyme-debug
new file mode 100755
index 0000000000..fb1620aa5c
--- /dev/null
+++ b/scripts/misc/notifyme-debug
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+# This is a sample NUT notification script aimed to aid debugging of upsmon
+# behavior. It creates or appends to a log file named per user ID in the
+# temporary location with an entry per line like this:
+#   Sat Apr  6 17:23:06 UTC 2024    [uid=77(nut) gid=77(nut) groups=77(nut)]        COMMBAD [eco650]:        Communications with UPS eco650 lost     (1 tokens)
+#   Sat Apr  6 17:28:01 UTC 2024    [uid=77(nut) gid=77(nut) groups=77(nut)]        NOCOMM  [eco650]:        UPS eco650 is unavailable       (1 tokens)
+#
+# Copyright (C) 2023-2024 by Jim Klimov <jimklimov+nut@gmail.com>
+# Licensed under the terms of the Network UPS Tools source license (GPLv2+)
+
+printf '%s\t[%s]\t%s\t[%s]:\t%s\t(%s tokens)\n' "`date -u`" "`id`" "${NOTIFYTYPE-}" "${UPSNAME-}" "$*" "$#" >> "/tmp/notifyme-`id -u`.log"
diff --git a/scripts/python/Makefile.am b/scripts/python/Makefile.am
index 56eeaa97f4..29c1291e30 100644
--- a/scripts/python/Makefile.am
+++ b/scripts/python/Makefile.am
@@ -70,6 +70,7 @@ NUT_MONITOR_COMMON = \
 	app/locale/ru/LC_MESSAGES/NUT-Monitor.mo
 
 PYNUT_COMMON = \
+	module/nut_telnetlib.py \
 	module/README.adoc
 
 # Note: we both distribute and install the generated *.mo translation files
@@ -129,17 +130,20 @@ ACT_MSGFMT = { \
 	rm -f "$${OUTFILE}.tmpsrc" ; \
 }
 
-app/locale/fr/LC_MESSAGES/NUT-Monitor.mo: app/locale/fr/fr.po
+app/locale/fr/LC_MESSAGES/NUT-Monitor.mo: $(abs_builddir)/app/locale/fr/LC_MESSAGES/NUT-Monitor.mo
+$(abs_builddir)/app/locale/fr/LC_MESSAGES/NUT-Monitor.mo: app/locale/fr/fr.po
 	@$(MKDIR_P) "$(builddir)/app/locale/fr/LC_MESSAGES"
-	SRCFILE="$^"; OUTFILE="$@"; $(ACT_MSGFMT)
+	SRCFILE="$?"; OUTFILE="$@"; $(ACT_MSGFMT)
 
-app/locale/it/LC_MESSAGES/NUT-Monitor.mo: app/locale/it/it.po
+app/locale/it/LC_MESSAGES/NUT-Monitor.mo: $(abs_builddir)/app/locale/it/LC_MESSAGES/NUT-Monitor.mo
+$(abs_builddir)/app/locale/it/LC_MESSAGES/NUT-Monitor.mo: app/locale/it/it.po
 	@$(MKDIR_P) "$(builddir)/app/locale/it/LC_MESSAGES"
-	SRCFILE="$^"; OUTFILE="$@"; $(ACT_MSGFMT)
+	SRCFILE="$?"; OUTFILE="$@"; $(ACT_MSGFMT)
 
-app/locale/ru/LC_MESSAGES/NUT-Monitor.mo: app/locale/ru/ru.po
+app/locale/ru/LC_MESSAGES/NUT-Monitor.mo: $(abs_builddir)/app/locale/ru/LC_MESSAGES/NUT-Monitor.mo
+$(abs_builddir)/app/locale/ru/LC_MESSAGES/NUT-Monitor.mo: app/locale/ru/ru.po
 	@$(MKDIR_P) "$(builddir)/app/locale/ru/LC_MESSAGES"
-	SRCFILE="$^"; OUTFILE="$@"; $(ACT_MSGFMT)
+	SRCFILE="$?"; OUTFILE="$@"; $(ACT_MSGFMT)
 endif HAVE_MSGFMT
 
 if WITH_NUT_MONITOR_PY2GTK2
@@ -199,7 +203,7 @@ SPELLCHECK_SRC = \
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/python/README.adoc b/scripts/python/README.adoc
index 72e268063b..8770d4ca06 100644
--- a/scripts/python/README.adoc
+++ b/scripts/python/README.adoc
@@ -35,6 +35,21 @@ and protocol support.
 
 For one practical example, you can research `tests/NIT/nit.sh` in NUT sources.
 
+telnetlib
+^^^^^^^^^
+
+Historically, the `PyNUTClient` class relied on `telnetlib` module for socket
+communications with the NUT data server, which was provided as part of Python
+core installation with tested 2.6+ and 3.* versions. The module was, however,
+marked deprecated since Python 3.11 and not provided since 3.13. Due to this,
+as a quick stop-gap solution, NUT sources provide `nut_telnetlib.py` - a copy
+of the module from Python 3.10 installation, and no longer should require its
+presence in the Python deployment.
+
+A better solution would be to find or create a new layer for the constrained
+use-case of NUT client interactions with a data server, which do not need the
+fully fledged Telnet-like capabilities.
+
 app
 ~~~
 
diff --git a/scripts/python/module/Makefile.am b/scripts/python/module/Makefile.am
index fc46eab0ad..5eb650969c 100644
--- a/scripts/python/module/Makefile.am
+++ b/scripts/python/module/Makefile.am
@@ -16,7 +16,7 @@ check-local:
 tox: dist .pypi-tools-tox
 	tox
 
-EXTRA_DIST = tox.ini MANIFEST.in
+EXTRA_DIST = tox.ini MANIFEST.in nut_telnetlib.py
 
 NUT_SOURCE_GITREV_NUMERIC = @NUT_SOURCE_GITREV_NUMERIC@
 PYTHON = @PYTHON@
@@ -64,7 +64,9 @@ upload publish:
 	 esac
 
 # README.txt is also a part of module standard expectations
-.pypi-src: test_nutclient.py.in PyNUT.py.in setup.py.in README.adoc Makefile $(top_srcdir)/LICENSE-GPL3
+# nut_telnetlib.py is not converted from a .in template, it
+# does not even have a shebang line.
+.pypi-src: test_nutclient.py.in PyNUT.py.in setup.py.in nut_telnetlib.py README.adoc Makefile $(top_srcdir)/LICENSE-GPL3
 	@echo "  PYPI  Generate PyPI module source"
 	@rm -rf $(GENERATED_SRC) "$@"
 	@mkdir -p PyNUTClient
@@ -83,6 +85,7 @@ upload publish:
 		sed -e "s,[@]PYTHON[@],@PYTHON@," < "$(srcdir)/$${B}.in" > "PyNUTClient/$${B}" || exit ; \
 		if test -x "$(srcdir)/$${B}.in" ; then chmod +x "PyNUTClient/$${B}"; fi ; \
 	 done ; \
+	 cp -pf "$(srcdir)/nut_telnetlib.py" PyNUTClient/ || exit ; \
 	 cp -pf "$(srcdir)/README.adoc" README.txt || exit ; \
 	 cp -pf "$(top_srcdir)/LICENSE-GPL3" . || exit ; \
 	 echo "from . import PyNUT" > PyNUTClient/__init__.py || exit
diff --git a/scripts/python/module/PyNUT.py.in b/scripts/python/module/PyNUT.py.in
index 6f3c4ff510..6838fc373a 100644
--- a/scripts/python/module/PyNUT.py.in
+++ b/scripts/python/module/PyNUT.py.in
@@ -55,8 +55,20 @@
 # 2023-01-18 Jim Klimov <jimklimov+nut@gmail.com> - Version 1.6.0
 #            Added CheckUPSAvailable() method originally by Michal Hlavinka
 #            from 2013-01-07 RedHat/Fedora packaging
+#
+# 2024-07-01 Jim Klimov <jimklimov+nut@gmail.com> - Version 1.7.0
+#            Re-arranged dependency on telnetlib module (deprecated/removed
+#            since Python 3.11/3.13), so we can fall back on a privately
+#            stashed copy until a better solution is developed.
+#
 
-import telnetlib
+try:
+    import telnetlib
+except ModuleNotFoundError:
+    import os
+    if "true" == os.getenv('DEBUG', 'false'):
+        print( "[DEBUG] Fall back to private copy of telnetlib for PyNUTClient\n" )
+    import nut_telnetlib as telnetlib
 
 class PyNUTError( Exception ) :
     """ Base class for custom exceptions """
@@ -73,8 +85,8 @@ class PyNUTClient :
     __timeout     = None
     __srv_handler = None
 
-    __version     = "1.6.0"
-    __release     = "2023-01-18"
+    __version     = "1.7.0"
+    __release     = "2024-07-01"
 
 
     def __init__( self, host="127.0.0.1", port=3493, login=None, password=None, debug=False, timeout=5 ) :
diff --git a/scripts/python/module/nut_telnetlib.py b/scripts/python/module/nut_telnetlib.py
new file mode 100644
index 0000000000..21a83fda3d
--- /dev/null
+++ b/scripts/python/module/nut_telnetlib.py
@@ -0,0 +1,687 @@
+r"""TELNET client class.
+
+------
+This file has been copied for PyNUTClient fallback needs from Python 3.10
+(newer Python releases obsoleted the module) and not modified except for
+this notice.
+
+See https://github.com/python/cpython/blob/3.10/Lib/telnetlib.py as of
+https://raw.githubusercontent.com/python/cpython/60419a7e96577cf783b3b45bf3984f9fb0d7ddff/Lib/telnetlib.py
+and https://github.com/python/cpython/blob/3.10/LICENSE
+------
+
+Based on RFC 854: TELNET Protocol Specification, by J. Postel and
+J. Reynolds
+
+Example:
+
+>>> from telnetlib import Telnet
+>>> tn = Telnet('www.python.org', 79)   # connect to finger port
+>>> tn.write(b'guido\r\n')
+>>> print(tn.read_all())
+Login       Name               TTY         Idle    When    Where
+guido    Guido van Rossum      pts/2        <Dec  2 11:10> snag.cnri.reston..
+
+>>>
+
+Note that read_all() won't read until eof -- it just reads some data
+-- but it guarantees to read at least one byte unless EOF is hit.
+
+It is possible to pass a Telnet object to a selector in order to wait until
+more data is available.  Note that in this case, read_eager() may return b''
+even if there was data on the socket, because the protocol negotiation may have
+eaten the data.  This is why EOFError is needed in some cases to distinguish
+between "no data" and "connection closed" (since the socket also appears ready
+for reading when it is closed).
+
+To do:
+- option negotiation
+- timeout should be intrinsic to the connection object instead of an
+  option on one of the read calls only
+
+"""
+
+
+# Imported modules
+import sys
+import socket
+import selectors
+from time import monotonic as _time
+
+__all__ = ["Telnet"]
+
+# Tunable parameters
+DEBUGLEVEL = 0
+
+# Telnet protocol defaults
+TELNET_PORT = 23
+
+# Telnet protocol characters (don't change)
+IAC  = bytes([255]) # "Interpret As Command"
+DONT = bytes([254])
+DO   = bytes([253])
+WONT = bytes([252])
+WILL = bytes([251])
+theNULL = bytes([0])
+
+SE  = bytes([240])  # Subnegotiation End
+NOP = bytes([241])  # No Operation
+DM  = bytes([242])  # Data Mark
+BRK = bytes([243])  # Break
+IP  = bytes([244])  # Interrupt process
+AO  = bytes([245])  # Abort output
+AYT = bytes([246])  # Are You There
+EC  = bytes([247])  # Erase Character
+EL  = bytes([248])  # Erase Line
+GA  = bytes([249])  # Go Ahead
+SB =  bytes([250])  # Subnegotiation Begin
+
+
+# Telnet protocol options code (don't change)
+# These ones all come from arpa/telnet.h
+BINARY = bytes([0]) # 8-bit data path
+ECHO = bytes([1]) # echo
+RCP = bytes([2]) # prepare to reconnect
+SGA = bytes([3]) # suppress go ahead
+NAMS = bytes([4]) # approximate message size
+STATUS = bytes([5]) # give status
+TM = bytes([6]) # timing mark
+RCTE = bytes([7]) # remote controlled transmission and echo
+NAOL = bytes([8]) # negotiate about output line width
+NAOP = bytes([9]) # negotiate about output page size
+NAOCRD = bytes([10]) # negotiate about CR disposition
+NAOHTS = bytes([11]) # negotiate about horizontal tabstops
+NAOHTD = bytes([12]) # negotiate about horizontal tab disposition
+NAOFFD = bytes([13]) # negotiate about formfeed disposition
+NAOVTS = bytes([14]) # negotiate about vertical tab stops
+NAOVTD = bytes([15]) # negotiate about vertical tab disposition
+NAOLFD = bytes([16]) # negotiate about output LF disposition
+XASCII = bytes([17]) # extended ascii character set
+LOGOUT = bytes([18]) # force logout
+BM = bytes([19]) # byte macro
+DET = bytes([20]) # data entry terminal
+SUPDUP = bytes([21]) # supdup protocol
+SUPDUPOUTPUT = bytes([22]) # supdup output
+SNDLOC = bytes([23]) # send location
+TTYPE = bytes([24]) # terminal type
+EOR = bytes([25]) # end or record
+TUID = bytes([26]) # TACACS user identification
+OUTMRK = bytes([27]) # output marking
+TTYLOC = bytes([28]) # terminal location number
+VT3270REGIME = bytes([29]) # 3270 regime
+X3PAD = bytes([30]) # X.3 PAD
+NAWS = bytes([31]) # window size
+TSPEED = bytes([32]) # terminal speed
+LFLOW = bytes([33]) # remote flow control
+LINEMODE = bytes([34]) # Linemode option
+XDISPLOC = bytes([35]) # X Display Location
+OLD_ENVIRON = bytes([36]) # Old - Environment variables
+AUTHENTICATION = bytes([37]) # Authenticate
+ENCRYPT = bytes([38]) # Encryption option
+NEW_ENVIRON = bytes([39]) # New - Environment variables
+# the following ones come from
+# http://www.iana.org/assignments/telnet-options
+# Unfortunately, that document does not assign identifiers
+# to all of them, so we are making them up
+TN3270E = bytes([40]) # TN3270E
+XAUTH = bytes([41]) # XAUTH
+CHARSET = bytes([42]) # CHARSET
+RSP = bytes([43]) # Telnet Remote Serial Port
+COM_PORT_OPTION = bytes([44]) # Com Port Control Option
+SUPPRESS_LOCAL_ECHO = bytes([45]) # Telnet Suppress Local Echo
+TLS = bytes([46]) # Telnet Start TLS
+KERMIT = bytes([47]) # KERMIT
+SEND_URL = bytes([48]) # SEND-URL
+FORWARD_X = bytes([49]) # FORWARD_X
+PRAGMA_LOGON = bytes([138]) # TELOPT PRAGMA LOGON
+SSPI_LOGON = bytes([139]) # TELOPT SSPI LOGON
+PRAGMA_HEARTBEAT = bytes([140]) # TELOPT PRAGMA HEARTBEAT
+EXOPL = bytes([255]) # Extended-Options-List
+NOOPT = bytes([0])
+
+
+# poll/select have the advantage of not requiring any extra file descriptor,
+# contrarily to epoll/kqueue (also, they require a single syscall).
+if hasattr(selectors, 'PollSelector'):
+    _TelnetSelector = selectors.PollSelector
+else:
+    _TelnetSelector = selectors.SelectSelector
+
+
+class Telnet:
+
+    """Telnet interface class.
+
+    An instance of this class represents a connection to a telnet
+    server.  The instance is initially not connected; the open()
+    method must be used to establish a connection.  Alternatively, the
+    host name and optional port number can be passed to the
+    constructor, too.
+
+    Don't try to reopen an already connected instance.
+
+    This class has many read_*() methods.  Note that some of them
+    raise EOFError when the end of the connection is read, because
+    they can return an empty string for other reasons.  See the
+    individual doc strings.
+
+    read_until(expected, [timeout])
+        Read until the expected string has been seen, or a timeout is
+        hit (default is no timeout); may block.
+
+    read_all()
+        Read all data until EOF; may block.
+
+    read_some()
+        Read at least one byte or EOF; may block.
+
+    read_very_eager()
+        Read all data available already queued or on the socket,
+        without blocking.
+
+    read_eager()
+        Read either data already queued or some data available on the
+        socket, without blocking.
+
+    read_lazy()
+        Read all data in the raw queue (processing it first), without
+        doing any socket I/O.
+
+    read_very_lazy()
+        Reads all data in the cooked queue, without doing any socket
+        I/O.
+
+    read_sb_data()
+        Reads available data between SB ... SE sequence. Don't block.
+
+    set_option_negotiation_callback(callback)
+        Each time a telnet option is read on the input flow, this callback
+        (if set) is called with the following parameters :
+        callback(telnet socket, command, option)
+            option will be chr(0) when there is no option.
+        No other action is done afterwards by telnetlib.
+
+    """
+
+    def __init__(self, host=None, port=0,
+                 timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+        """Constructor.
+
+        When called without arguments, create an unconnected instance.
+        With a hostname argument, it connects the instance; port number
+        and timeout are optional.
+        """
+        self.debuglevel = DEBUGLEVEL
+        self.host = host
+        self.port = port
+        self.timeout = timeout
+        self.sock = None
+        self.rawq = b''
+        self.irawq = 0
+        self.cookedq = b''
+        self.eof = 0
+        self.iacseq = b'' # Buffer for IAC sequence.
+        self.sb = 0 # flag for SB and SE sequence.
+        self.sbdataq = b''
+        self.option_callback = None
+        if host is not None:
+            self.open(host, port, timeout)
+
+    def open(self, host, port=0, timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
+        """Connect to a host.
+
+        The optional second argument is the port number, which
+        defaults to the standard telnet port (23).
+
+        Don't try to reopen an already connected instance.
+        """
+        self.eof = 0
+        if not port:
+            port = TELNET_PORT
+        self.host = host
+        self.port = port
+        self.timeout = timeout
+        sys.audit("telnetlib.Telnet.open", self, host, port)
+        self.sock = socket.create_connection((host, port), timeout)
+
+    def __del__(self):
+        """Destructor -- close the connection."""
+        self.close()
+
+    def msg(self, msg, *args):
+        """Print a debug message, when the debug level is > 0.
+
+        If extra arguments are present, they are substituted in the
+        message using the standard string formatting operator.
+
+        """
+        if self.debuglevel > 0:
+            print('Telnet(%s,%s):' % (self.host, self.port), end=' ')
+            if args:
+                print(msg % args)
+            else:
+                print(msg)
+
+    def set_debuglevel(self, debuglevel):
+        """Set the debug level.
+
+        The higher it is, the more debug output you get (on sys.stdout).
+
+        """
+        self.debuglevel = debuglevel
+
+    def close(self):
+        """Close the connection."""
+        sock = self.sock
+        self.sock = None
+        self.eof = True
+        self.iacseq = b''
+        self.sb = 0
+        if sock:
+            sock.close()
+
+    def get_socket(self):
+        """Return the socket object used internally."""
+        return self.sock
+
+    def fileno(self):
+        """Return the fileno() of the socket object used internally."""
+        return self.sock.fileno()
+
+    def write(self, buffer):
+        """Write a string to the socket, doubling any IAC characters.
+
+        Can block if the connection is blocked.  May raise
+        OSError if the connection is closed.
+
+        """
+        if IAC in buffer:
+            buffer = buffer.replace(IAC, IAC+IAC)
+        sys.audit("telnetlib.Telnet.write", self, buffer)
+        self.msg("send %r", buffer)
+        self.sock.sendall(buffer)
+
+    def read_until(self, match, timeout=None):
+        """Read until a given string is encountered or until timeout.
+
+        When no match is found, return whatever is available instead,
+        possibly the empty string.  Raise EOFError if the connection
+        is closed and no cooked data is available.
+
+        """
+        n = len(match)
+        self.process_rawq()
+        i = self.cookedq.find(match)
+        if i >= 0:
+            i = i+n
+            buf = self.cookedq[:i]
+            self.cookedq = self.cookedq[i:]
+            return buf
+        if timeout is not None:
+            deadline = _time() + timeout
+        with _TelnetSelector() as selector:
+            selector.register(self, selectors.EVENT_READ)
+            while not self.eof:
+                if selector.select(timeout):
+                    i = max(0, len(self.cookedq)-n)
+                    self.fill_rawq()
+                    self.process_rawq()
+                    i = self.cookedq.find(match, i)
+                    if i >= 0:
+                        i = i+n
+                        buf = self.cookedq[:i]
+                        self.cookedq = self.cookedq[i:]
+                        return buf
+                if timeout is not None:
+                    timeout = deadline - _time()
+                    if timeout < 0:
+                        break
+        return self.read_very_lazy()
+
+    def read_all(self):
+        """Read all data until EOF; block until connection closed."""
+        self.process_rawq()
+        while not self.eof:
+            self.fill_rawq()
+            self.process_rawq()
+        buf = self.cookedq
+        self.cookedq = b''
+        return buf
+
+    def read_some(self):
+        """Read at least one byte of cooked data unless EOF is hit.
+
+        Return b'' if EOF is hit.  Block if no data is immediately
+        available.
+
+        """
+        self.process_rawq()
+        while not self.cookedq and not self.eof:
+            self.fill_rawq()
+            self.process_rawq()
+        buf = self.cookedq
+        self.cookedq = b''
+        return buf
+
+    def read_very_eager(self):
+        """Read everything that's possible without blocking in I/O (eager).
+
+        Raise EOFError if connection closed and no cooked data
+        available.  Return b'' if no cooked data available otherwise.
+        Don't block unless in the midst of an IAC sequence.
+
+        """
+        self.process_rawq()
+        while not self.eof and self.sock_avail():
+            self.fill_rawq()
+            self.process_rawq()
+        return self.read_very_lazy()
+
+    def read_eager(self):
+        """Read readily available data.
+
+        Raise EOFError if connection closed and no cooked data
+        available.  Return b'' if no cooked data available otherwise.
+        Don't block unless in the midst of an IAC sequence.
+
+        """
+        self.process_rawq()
+        while not self.cookedq and not self.eof and self.sock_avail():
+            self.fill_rawq()
+            self.process_rawq()
+        return self.read_very_lazy()
+
+    def read_lazy(self):
+        """Process and return data that's already in the queues (lazy).
+
+        Raise EOFError if connection closed and no data available.
+        Return b'' if no cooked data available otherwise.  Don't block
+        unless in the midst of an IAC sequence.
+
+        """
+        self.process_rawq()
+        return self.read_very_lazy()
+
+    def read_very_lazy(self):
+        """Return any data available in the cooked queue (very lazy).
+
+        Raise EOFError if connection closed and no data available.
+        Return b'' if no cooked data available otherwise.  Don't block.
+
+        """
+        buf = self.cookedq
+        self.cookedq = b''
+        if not buf and self.eof and not self.rawq:
+            raise EOFError('telnet connection closed')
+        return buf
+
+    def read_sb_data(self):
+        """Return any data available in the SB ... SE queue.
+
+        Return b'' if no SB ... SE available. Should only be called
+        after seeing a SB or SE command. When a new SB command is
+        found, old unread SB data will be discarded. Don't block.
+
+        """
+        buf = self.sbdataq
+        self.sbdataq = b''
+        return buf
+
+    def set_option_negotiation_callback(self, callback):
+        """Provide a callback function called after each receipt of a telnet option."""
+        self.option_callback = callback
+
+    def process_rawq(self):
+        """Transfer from raw queue to cooked queue.
+
+        Set self.eof when connection is closed.  Don't block unless in
+        the midst of an IAC sequence.
+
+        """
+        buf = [b'', b'']
+        try:
+            while self.rawq:
+                c = self.rawq_getchar()
+                if not self.iacseq:
+                    if c == theNULL:
+                        continue
+                    if c == b"\021":
+                        continue
+                    if c != IAC:
+                        buf[self.sb] = buf[self.sb] + c
+                        continue
+                    else:
+                        self.iacseq += c
+                elif len(self.iacseq) == 1:
+                    # 'IAC: IAC CMD [OPTION only for WILL/WONT/DO/DONT]'
+                    if c in (DO, DONT, WILL, WONT):
+                        self.iacseq += c
+                        continue
+
+                    self.iacseq = b''
+                    if c == IAC:
+                        buf[self.sb] = buf[self.sb] + c
+                    else:
+                        if c == SB: # SB ... SE start.
+                            self.sb = 1
+                            self.sbdataq = b''
+                        elif c == SE:
+                            self.sb = 0
+                            self.sbdataq = self.sbdataq + buf[1]
+                            buf[1] = b''
+                        if self.option_callback:
+                            # Callback is supposed to look into
+                            # the sbdataq
+                            self.option_callback(self.sock, c, NOOPT)
+                        else:
+                            # We can't offer automatic processing of
+                            # suboptions. Alas, we should not get any
+                            # unless we did a WILL/DO before.
+                            self.msg('IAC %d not recognized' % ord(c))
+                elif len(self.iacseq) == 2:
+                    cmd = self.iacseq[1:2]
+                    self.iacseq = b''
+                    opt = c
+                    if cmd in (DO, DONT):
+                        self.msg('IAC %s %d',
+                            cmd == DO and 'DO' or 'DONT', ord(opt))
+                        if self.option_callback:
+                            self.option_callback(self.sock, cmd, opt)
+                        else:
+                            self.sock.sendall(IAC + WONT + opt)
+                    elif cmd in (WILL, WONT):
+                        self.msg('IAC %s %d',
+                            cmd == WILL and 'WILL' or 'WONT', ord(opt))
+                        if self.option_callback:
+                            self.option_callback(self.sock, cmd, opt)
+                        else:
+                            self.sock.sendall(IAC + DONT + opt)
+        except EOFError: # raised by self.rawq_getchar()
+            self.iacseq = b'' # Reset on EOF
+            self.sb = 0
+            pass
+        self.cookedq = self.cookedq + buf[0]
+        self.sbdataq = self.sbdataq + buf[1]
+
+    def rawq_getchar(self):
+        """Get next char from raw queue.
+
+        Block if no data is immediately available.  Raise EOFError
+        when connection is closed.
+
+        """
+        if not self.rawq:
+            self.fill_rawq()
+            if self.eof:
+                raise EOFError
+        c = self.rawq[self.irawq:self.irawq+1]
+        self.irawq = self.irawq + 1
+        if self.irawq >= len(self.rawq):
+            self.rawq = b''
+            self.irawq = 0
+        return c
+
+    def fill_rawq(self):
+        """Fill raw queue from exactly one recv() system call.
+
+        Block if no data is immediately available.  Set self.eof when
+        connection is closed.
+
+        """
+        if self.irawq >= len(self.rawq):
+            self.rawq = b''
+            self.irawq = 0
+        # The buffer size should be fairly small so as to avoid quadratic
+        # behavior in process_rawq() above
+        buf = self.sock.recv(50)
+        self.msg("recv %r", buf)
+        self.eof = (not buf)
+        self.rawq = self.rawq + buf
+
+    def sock_avail(self):
+        """Test whether data is available on the socket."""
+        with _TelnetSelector() as selector:
+            selector.register(self, selectors.EVENT_READ)
+            return bool(selector.select(0))
+
+    def interact(self):
+        """Interaction function, emulates a very dumb telnet client."""
+        if sys.platform == "win32":
+            self.mt_interact()
+            return
+        with _TelnetSelector() as selector:
+            selector.register(self, selectors.EVENT_READ)
+            selector.register(sys.stdin, selectors.EVENT_READ)
+
+            while True:
+                for key, events in selector.select():
+                    if key.fileobj is self:
+                        try:
+                            text = self.read_eager()
+                        except EOFError:
+                            print('*** Connection closed by remote host ***')
+                            return
+                        if text:
+                            sys.stdout.write(text.decode('ascii'))
+                            sys.stdout.flush()
+                    elif key.fileobj is sys.stdin:
+                        line = sys.stdin.readline().encode('ascii')
+                        if not line:
+                            return
+                        self.write(line)
+
+    def mt_interact(self):
+        """Multithreaded version of interact()."""
+        import _thread
+        _thread.start_new_thread(self.listener, ())
+        while 1:
+            line = sys.stdin.readline()
+            if not line:
+                break
+            self.write(line.encode('ascii'))
+
+    def listener(self):
+        """Helper for mt_interact() -- this executes in the other thread."""
+        while 1:
+            try:
+                data = self.read_eager()
+            except EOFError:
+                print('*** Connection closed by remote host ***')
+                return
+            if data:
+                sys.stdout.write(data.decode('ascii'))
+            else:
+                sys.stdout.flush()
+
+    def expect(self, list, timeout=None):
+        """Read until one from a list of a regular expressions matches.
+
+        The first argument is a list of regular expressions, either
+        compiled (re.Pattern instances) or uncompiled (strings).
+        The optional second argument is a timeout, in seconds; default
+        is no timeout.
+
+        Return a tuple of three items: the index in the list of the
+        first regular expression that matches; the re.Match object
+        returned; and the text read up till and including the match.
+
+        If EOF is read and no text was read, raise EOFError.
+        Otherwise, when nothing matches, return (-1, None, text) where
+        text is the text received so far (may be the empty string if a
+        timeout happened).
+
+        If a regular expression ends with a greedy match (e.g. '.*')
+        or if more than one expression can match the same input, the
+        results are undeterministic, and may depend on the I/O timing.
+
+        """
+        re = None
+        list = list[:]
+        indices = range(len(list))
+        for i in indices:
+            if not hasattr(list[i], "search"):
+                if not re: import re
+                list[i] = re.compile(list[i])
+        if timeout is not None:
+            deadline = _time() + timeout
+        with _TelnetSelector() as selector:
+            selector.register(self, selectors.EVENT_READ)
+            while not self.eof:
+                self.process_rawq()
+                for i in indices:
+                    m = list[i].search(self.cookedq)
+                    if m:
+                        e = m.end()
+                        text = self.cookedq[:e]
+                        self.cookedq = self.cookedq[e:]
+                        return (i, m, text)
+                if timeout is not None:
+                    ready = selector.select(timeout)
+                    timeout = deadline - _time()
+                    if not ready:
+                        if timeout < 0:
+                            break
+                        else:
+                            continue
+                self.fill_rawq()
+        text = self.read_very_lazy()
+        if not text and self.eof:
+            raise EOFError
+        return (-1, None, text)
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, type, value, traceback):
+        self.close()
+
+
+def test():
+    """Test program for telnetlib.
+
+    Usage: python telnetlib.py [-d] ... [host [port]]
+
+    Default host is localhost; default port is 23.
+
+    """
+    debuglevel = 0
+    while sys.argv[1:] and sys.argv[1] == '-d':
+        debuglevel = debuglevel+1
+        del sys.argv[1]
+    host = 'localhost'
+    if sys.argv[1:]:
+        host = sys.argv[1]
+    port = 0
+    if sys.argv[2:]:
+        portstr = sys.argv[2]
+        try:
+            port = int(portstr)
+        except ValueError:
+            port = socket.getservbyname(portstr, 'tcp')
+    with Telnet() as tn:
+        tn.set_debuglevel(debuglevel)
+        tn.open(host, port, timeout=0.5)
+        tn.interact()
+
+if __name__ == '__main__':
+    test()
diff --git a/scripts/python/module/setup.py.in b/scripts/python/module/setup.py.in
index 18f956d20c..c6276fd2f2 100644
--- a/scripts/python/module/setup.py.in
+++ b/scripts/python/module/setup.py.in
@@ -30,7 +30,11 @@ setup(
     #data_files =	[('', ['tox.ini'])],
     #scripts    =	['PyNUTClient/test_nutclient.py', 'PyNUTClient/__init__.py'],
     python_requires =	'>=2.6',
-    # install_requires =	['telnetlib'],	# NOTE: telnetlib.py is part of Python core for tested 2.x and 3.x versions, not something 'pip' can download
+    # NOTE: telnetlib.py is part of Python core for tested 2.x and 3.x versions,
+    # not something 'pip' can download as a package. It is deprecated since 3.11
+    # and removed since 3.13, so as a hotfix, NUT provides a copy nut_telnetlib.py
+    # (taken from Python 3.10 - the latest one without a deprecation warning).
+    # install_requires =	['telnetlib'],
     keywords =	['pypi', 'cicd', 'python', 'nut', 'Network UPS Tools'],
     classifiers = [
         "Development Status :: 5 - Production/Stable",
diff --git a/scripts/python/module/test_nutclient.py.in b/scripts/python/module/test_nutclient.py.in
index c9b1431447..8fc2796c67 100755
--- a/scripts/python/module/test_nutclient.py.in
+++ b/scripts/python/module/test_nutclient.py.in
@@ -13,13 +13,16 @@ if __name__ == "__main__" :
     NUT_USER = os.getenv('NUT_USER', None)
     NUT_PASS = os.getenv('NUT_PASS', None)
 
+    NUT_DEBUG = ("true" == os.getenv('DEBUG', 'false') or os.getenv('NUT_DEBUG_LEVEL', None) is not None)
+
     # Account "unexpected" failures (more due to coding than circumstances)
     # e.g. lack of protected access when no credentials were passed is okay
     failed = []
 
     print( "PyNUTClient test..." )
     #nut    = PyNUT.PyNUTClient( debug=True, port=NUT_PORT )
-    nut    = PyNUT.PyNUTClient( login=NUT_USER, password=NUT_PASS, debug=True, host=NUT_HOST, port=NUT_PORT )
+    #nut    = PyNUT.PyNUTClient( login=NUT_USER, password=NUT_PASS, debug=True, host=NUT_HOST, port=NUT_PORT )
+    nut    = PyNUT.PyNUTClient( login=NUT_USER, password=NUT_PASS, debug=NUT_DEBUG, host=NUT_HOST, port=NUT_PORT )
     #nut    = PyNUT.PyNUTClient( login="upsadmin", password="upsadmin", debug=True, port=NUT_PORT )
 
     print( 80*"-" + "\nTesting 'GetUPSList' :")
diff --git a/scripts/subdriver/gen-snmp-subdriver.sh b/scripts/subdriver/gen-snmp-subdriver.sh
index 0fba35e5d8..9d7a24e064 100755
--- a/scripts/subdriver/gen-snmp-subdriver.sh
+++ b/scripts/subdriver/gen-snmp-subdriver.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # an auxiliary script to produce a "stub" snmp-ups subdriver from
 # SNMP data from a real agent or from dump files
diff --git a/scripts/subdriver/gen-usbhid-subdriver.sh b/scripts/subdriver/gen-usbhid-subdriver.sh
index 35b8311e15..75f3ec269b 100755
--- a/scripts/subdriver/gen-usbhid-subdriver.sh
+++ b/scripts/subdriver/gen-usbhid-subdriver.sh
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 # an auxiliary script to produce a "stub" usbhid-ups subdriver from
 # the output of
diff --git a/scripts/systemd/.gitignore b/scripts/systemd/.gitignore
index a39ac8db55..560c249b43 100644
--- a/scripts/systemd/.gitignore
+++ b/scripts/systemd/.gitignore
@@ -3,7 +3,6 @@
 /nut-common-tmpfiles.conf
 /nut-driver.service
 /nut-driver@.service
-/nut-driver.target
 /nut-monitor.service
 /nut-server.service
 /nutshutdown
diff --git a/scripts/systemd/Makefile.am b/scripts/systemd/Makefile.am
index 7a0f37f7b9..e1a5fa5231 100644
--- a/scripts/systemd/Makefile.am
+++ b/scripts/systemd/Makefile.am
@@ -16,10 +16,15 @@ systemdsystemunit_DATA = \
         nut-driver.target   \
         nut.target
 
+if !WITH_LIBSYSTEMD_INHIBITOR
+systemdsystemunit_DATA += \
+        nut-sleep.service
+endif !WITH_LIBSYSTEMD_INHIBITOR
+
 systemdtmpfiles_DATA = \
         nut-common-tmpfiles.conf
 
-EXTRA_DIST += nut-driver.target nut.target
+EXTRA_DIST += nut-driver.target nut.target nut-sleep.service
 
 systemdshutdown_SCRIPTS = nutshutdown
 
@@ -27,9 +32,9 @@ libexec_SCRIPTS = ../upsdrvsvcctl/nut-driver-enumerator.sh
 
 sbin_SCRIPTS = ../upsdrvsvcctl/upsdrvsvcctl
 
-else
+else !HAVE_SYSTEMD
 EXTRA_DIST += \
-	nut-driver@.service.in nut-monitor.service.in \
+	nut-driver@.service.in nut-monitor.service.in nut-sleep.service \
 	nut-server.service.in nutshutdown.in nut-driver.target nut.target \
 	nut-driver-enumerator.path.in nut-driver-enumerator.service.in \
 	nut-driver-enumerator-daemon-activator.path.in \
@@ -37,14 +42,14 @@ EXTRA_DIST += \
 	nut-driver-enumerator-daemon.service.in
 
 # NOTE: Do not EXTRA_DIST nut-common-tmpfiles.conf.in - it is generated per build
-endif
+endif !HAVE_SYSTEMD
 
 SPELLCHECK_SRC = README.adoc
 
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/systemd/README.adoc b/scripts/systemd/README.adoc
index 8c66601dce..e164c2bc2a 100644
--- a/scripts/systemd/README.adoc
+++ b/scripts/systemd/README.adoc
@@ -11,6 +11,16 @@ These files are automatically installed, upon detection (at `configure` time)
 of a systemd enabled target system, or if corresponding configuration options
 were requested.
 
+If you need to tweak some of the services, prefer to use systemd "drop-in"
+configuration files rather than editing the installed unit files directly
+(lest your changes be lost upon upgrade), e.g.:
+----
+# cat /etc/systemd/system/nut-monitor.service.d/debug.conf
+[Service]
+Environment="NUT_DEBUG_PID=yes"
+----
+...followed up by `systemctl daemon-reload` and a restart of the unit itself.
+
 This also uses the `nut-driver-enumerator.sh` (service and implementation
 method) and `upsdrvsvcctl` (tool) to manage NUT drivers as service instances
 located in `../upsdrvsvcctl/` source subdirectory.
diff --git a/scripts/systemd/nut-driver-enumerator-daemon-activator.path.in b/scripts/systemd/nut-driver-enumerator-daemon-activator.path.in
index 615ce9fe57..02070bafba 100644
--- a/scripts/systemd/nut-driver-enumerator-daemon-activator.path.in
+++ b/scripts/systemd/nut-driver-enumerator-daemon-activator.path.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
@@ -8,7 +8,7 @@
 # Trigger restart of nut-driver-enumerator-daemon-activator.service
 # whenever ups.conf is edited, which would cause reload-or-restart
 # of the nut-driver-enumerator-daemon.service for actual reconfig.
-Description=Network UPS Tools - Trigger restart of nut-driver-enumerator-daemon.service whenever ups.conf is edited
+Description=Network UPS Tools - Trigger reload-or-restart of nut-driver-enumerator-daemon.service whenever ups.conf is edited
 Conflicts=nut-driver-enumerator.service nut-driver-enumerator.path
 After=local-fs.target
 Before=nut-driver.target
diff --git a/scripts/systemd/nut-driver-enumerator-daemon-activator.service.in b/scripts/systemd/nut-driver-enumerator-daemon-activator.service.in
index 86944fc3ff..5e8eca32ff 100644
--- a/scripts/systemd/nut-driver-enumerator-daemon-activator.service.in
+++ b/scripts/systemd/nut-driver-enumerator-daemon-activator.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
@@ -26,6 +26,17 @@ Type=oneshot
 # Non-blocking systemd message posting should not take long,
 # or should be aborted and retried if it does (system bugs)
 TimeoutStartSec=10s
+# If some process is writing the ups.conf file, it can be interpreted in
+# some conditions by .path unit as many events requiring it to start -
+# and eventually this gets throttled as a quickly started-restarted unit.
+# While it should be permitted for manual start (likely .path trigger too)
+# after interval expiration, this might race-condition to not detect some
+# latest update into the configuration file if it happens after the main
+# script loop has slurped intermediate state of device config.
+# Note: Using the older but still supported Service/StartLimitInterval
+# see https://lists.freedesktop.org/archives/systemd-devel/2017-July/039255.html
+# for broader compatibility.
+StartLimitInterval=0
 ExecStart=/bin/systemctl reload-or-restart --no-block nut-driver-enumerator-daemon.service
 
 [Install]
diff --git a/scripts/systemd/nut-driver-enumerator-daemon.service.in b/scripts/systemd/nut-driver-enumerator-daemon.service.in
index af13ab4e29..8dacea7384 100644
--- a/scripts/systemd/nut-driver-enumerator-daemon.service.in
+++ b/scripts/systemd/nut-driver-enumerator-daemon.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nut-driver-enumerator.path.in b/scripts/systemd/nut-driver-enumerator.path.in
index 09b9fdddb4..35878e051d 100644
--- a/scripts/systemd/nut-driver-enumerator.path.in
+++ b/scripts/systemd/nut-driver-enumerator.path.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nut-driver-enumerator.service.in b/scripts/systemd/nut-driver-enumerator.service.in
index bab6feec95..067b149d92 100644
--- a/scripts/systemd/nut-driver-enumerator.service.in
+++ b/scripts/systemd/nut-driver-enumerator.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nut-driver.target b/scripts/systemd/nut-driver.target
index 0055e469d4..95382674be 100644
--- a/scripts/systemd/nut-driver.target
+++ b/scripts/systemd/nut-driver.target
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nut-driver@.service.in b/scripts/systemd/nut-driver@.service.in
index 1a1a04a4f0..5a0a7edb03 100644
--- a/scripts/systemd/nut-driver@.service.in
+++ b/scripts/systemd/nut-driver@.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
@@ -47,6 +47,7 @@ PartOf=nut-driver.target
 
 [Service]
 Environment=NUT_IGNORE_NOWAIT=true
+Environment=NUT_QUIET_INIT_NDE_WARNING=true
 EnvironmentFile=-@CONFPATH@/nut.conf
 SyslogIdentifier=%N
 ExecStartPre=-@SYSTEMD_TMPFILES_PROGRAM@ --create @systemdtmpfilesdir@/nut-common-tmpfiles.conf
diff --git a/scripts/systemd/nut-monitor.service.in b/scripts/systemd/nut-monitor.service.in
index 25747fd30b..7b7316b4e1 100644
--- a/scripts/systemd/nut-monitor.service.in
+++ b/scripts/systemd/nut-monitor.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nut-server.service.in b/scripts/systemd/nut-server.service.in
index 33f3b313d4..780a47beef 100644
--- a/scripts/systemd/nut-server.service.in
+++ b/scripts/systemd/nut-server.service.in
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
@@ -26,6 +26,21 @@ Before=nut-monitor.service
 PartOf=nut.target
 
 [Service]
+# A busy server can be monitoring a lot of devices as well as replying
+# to many clients. The "infinity" definition is actually capped by OS
+# settings and hardcoded defaults; typically can be 65535+ nowadays.
+# On 64-bit distros this can well be set into hundreds of thousands
+# as well (though note each connnection has a CPU and RAM overhead
+# so one can strike physical limits upon deployment and/or bring the
+# poorly sized system to a crawl, or worse). On a running system you
+# can check /proc/$MAINPID/limits for active ulimits of the process.
+# From my experiments, up to 1048576 can be set, but any larger value
+# falls back to 65536. The systemd definition of "infinity" is 65536
+# too (or maybe it falls back to that); though this may be OS/distro
+# limitation and not systemd fault specifically.
+#LimitNOFILE=infinity
+#LimitNOFILE=65535
+LimitNOFILE=1048576
 EnvironmentFile=-@CONFPATH@/nut.conf
 SyslogIdentifier=%N
 # Note: foreground mode "-F" by default skips writing a PID file (and
@@ -34,6 +49,7 @@ SyslogIdentifier=%N
 ExecStartPre=-@SYSTEMD_TMPFILES_PROGRAM@ --create @systemdtmpfilesdir@/nut-common-tmpfiles.conf
 ExecStart=@SBINDIR@/upsd @SYSTEMD_DAEMON_ARGS_UPSD@
 ExecReload=@SBINDIR@/upsd -c reload -P $MAINPID
+ExecStartPost=-/bin/grep -E 'Units|Max open files' /proc/${MAINPID}/limits
 # No tracking for PIDFile path and service attribute here (it might not
 # even exist).
 # If "-FF" or background-daemon mode is used, so that PID file exists
diff --git a/scripts/systemd/nut-sleep.service b/scripts/systemd/nut-sleep.service
new file mode 100644
index 0000000000..bb93c8c832
--- /dev/null
+++ b/scripts/systemd/nut-sleep.service
@@ -0,0 +1,26 @@
+# Network UPS Tools (NUT) systemd integration
+# Copyright (C) 2011-2024 by NUT contirbutors
+# Distributed under the terms of GPLv2+
+# See https://networkupstools.org/
+# and https://github.com/networkupstools/nut/
+
+# A rather blunt solution for system sleeping support, for cases where
+# we can not use a native libssytemd "inhibitor interface". This helps
+# avoid NUT shutting down a woken-up system just because its power state
+# was critical before the sleep, and a next-read timestamp was not seen
+# (deemed to be a stale UPS, meaning lost comms during critical state,
+# so must go down ASAP).
+
+[Unit]
+Description=Network UPS Tools - sleep hook
+Before=sleep.target
+StopWhenUnneeded=yes
+
+[Service]
+Type=oneshot
+RemainAfterExit=yes
+ExecStart=/usr/bin/systemctl stop nut.target
+ExecStop=/usr/bin/systemctl start --no-block nut.target
+
+[Install]
+WantedBy=sleep.target
diff --git a/scripts/systemd/nut.target b/scripts/systemd/nut.target
index 3974fed4bf..b8dce11e71 100644
--- a/scripts/systemd/nut.target
+++ b/scripts/systemd/nut.target
@@ -1,5 +1,5 @@
 # Network UPS Tools (NUT) systemd integration
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Distributed under the terms of GPLv2+
 # See https://networkupstools.org/
 # and https://github.com/networkupstools/nut/
diff --git a/scripts/systemd/nutshutdown.in b/scripts/systemd/nutshutdown.in
index 8625e167d9..0c60ec9e64 100755
--- a/scripts/systemd/nutshutdown.in
+++ b/scripts/systemd/nutshutdown.in
@@ -8,7 +8,7 @@
 # and their configuration files to be present locally and on still-mounted
 # filesystems (may be read-only).
 #
-# Copyright (C) 2011-2023 by NUT contirbutors
+# Copyright (C) 2011-2024 by NUT contirbutors
 # Michal Hlavinka, Laurent Bigonville, Arnaud Quette, Jim Klimov et al.
 #
 # See https://networkupstools.org/
@@ -51,6 +51,8 @@ if @SBINDIR@/upsmon -K >/dev/null 2>&1; then
             echo "$0: Commanding UPSes (if any) to shutdown" >&2
             [ -w /dev/console ] && echo "`TZ=UTC LANG=C date`: $0: Commanding UPSes (if any) to shutdown" >/dev/console || true
         }
+        NUT_QUIET_INIT_NDE_WARNING=true
+        export NUT_QUIET_INIT_NDE_WARNING
         @SBINDIR@/upsdrvctl shutdown || echo "$0: Something failed about UPS shutdown commands" >&2
     fi
 
diff --git a/scripts/udev/Makefile.am b/scripts/udev/Makefile.am
index e0576d952c..a63107d980 100644
--- a/scripts/udev/Makefile.am
+++ b/scripts/udev/Makefile.am
@@ -41,21 +41,21 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
-#	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+#	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 # NOTE: Portable suffix rules do not allow prerequisites, so we shim them here
 # by a wildcard target in case the make implementation can put the two together.
 *-spellchecked: Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 
 .sample.sample-spellchecked:
-	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 .in.in-spellchecked:
-	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 spellcheck spellcheck-interactive spellcheck-sortdict:
-	+$(MAKE) -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC="$(SPELLCHECK_SRC)" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
+	+$(MAKE) $(AM_MAKEFLAGS) -f $(top_builddir)/docs/Makefile $(AM_MAKEFILE) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC="$(SPELLCHECK_SRC)" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
 CLEANFILES += *-spellchecked
diff --git a/scripts/upower/95-upower-hid.hwdb b/scripts/upower/95-upower-hid.hwdb
index ba554bde30..41da8c059f 100644
--- a/scripts/upower/95-upower-hid.hwdb
+++ b/scripts/upower/95-upower-hid.hwdb
@@ -153,7 +153,9 @@ usb:v0D9Fp00A6*
  UPOWER_VENDOR=PowerCOM
 
 # Liebert
+usb:v10AFp0000*
 usb:v10AFp0001*
+usb:v10AFp0002*
 usb:v10AFp0004*
 usb:v10AFp0008*
  UPOWER_BATTERY_TYPE=ups
diff --git a/scripts/upsdrvsvcctl/Makefile.am b/scripts/upsdrvsvcctl/Makefile.am
index 4cb4ad69d2..03adf8e1c4 100644
--- a/scripts/upsdrvsvcctl/Makefile.am
+++ b/scripts/upsdrvsvcctl/Makefile.am
@@ -17,7 +17,7 @@ SPELLCHECK_SRC = README.adoc
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/scripts/upsdrvsvcctl/nut-driver-enumerator.sh.in b/scripts/upsdrvsvcctl/nut-driver-enumerator.sh.in
index 7b13dc4eec..aee3d0b454 100644
--- a/scripts/upsdrvsvcctl/nut-driver-enumerator.sh.in
+++ b/scripts/upsdrvsvcctl/nut-driver-enumerator.sh.in
@@ -363,6 +363,11 @@ upslist_savednames_find_missing() {
     # Verify that all existing service units have a saved DEVICE name
     # Report those that do not have a value there (any value) so we can
     # amend those quickly after an upgrade. Otherwise we trust these.
+    # Return codes:
+    #    0) Some services were defined and at least one had DEVICE values
+    #       (those that did not are reported in stdout)
+    #    1) No services defined yet (empty stdout)
+    #    2) All service units do not have DEVICE values (all reported in stdout)
 
     # Get full instance names from system and from props
     SVCINSTS="`$hook_listInstances_raw`" && [ "${#SVCINSTS}" != 0 ] || return 1
@@ -370,14 +375,21 @@ upslist_savednames_find_missing() {
     SVCINST_PROPS="`$hook_findSavedDeviceName`" && [ "${#SVCINST_PROPS}" != 0 ] \
     || { echo $SVCINSTS ; return 2; }
 
-    # Find services which do not have saved names in props
+    # Find and report services which do *not* have saved device names in
+    # props (do not report those that have a non-trivial prop value):
+    # whether an empty value or completely absent from the list
     for SVCINST in $SVCINSTS ; do
-        echo "$SVCINST_PROPS" | grep -E "^${SVCINST_PROPS}\t"'$' >/dev/null || echo "$SVCINST"
+        echo "$SVCINST_PROPS" | grep -E "^${SVCINST}${TABCHAR}"'$' >/dev/null && echo "$SVCINST"
+        echo "$SVCINST_PROPS" | grep -E "^${SVCINST}${TABCHAR}" >/dev/null || echo "$SVCINST"
     done
+    return 0
 }
 
 upslist_savednames_find_mismatch() {
+    # NOTE: Not used currently (as of NUT v2.8.2)
     # TODO: Make use of this to fsck the enumerator configs
+    # TODO: Complete checking MD5 normalized names if original not hit
+    # TODO: Report all unit names if none has the DEVICE values? (code 2)
     #
     # Verify that all existing service units have a saved DEVICE name
     # and that such name does match the unit instance's name (original
@@ -387,20 +399,30 @@ upslist_savednames_find_mismatch() {
     # This situation might occur in some errors, but the likely case
     # is updating from versions that did not track this info yet (but
     # upslist_savednames_find_missing() should have handled those).
+    # Return codes:
+    #    0) Some services were defined and at least one had DEVICE values
+    #       (those that did not are reported in stdout)
+    #    1) No services defined yet (empty stdout)
+    #    2) All service units do not have DEVICE values (empty stdout)
 
     # Get full instance names from system and from props
     SVCINSTS="`$hook_listInstances_raw`" && [ "${#SVCINSTS}" != 0 ] || return 1
     SVCINST_PROPS="`$hook_findSavedDeviceName`" && [ "${#SVCINST_PROPS}" != 0 ] || return 2
 
-    # Find services whose props exist but services do not
+    # Find services whose props exist but services themselves do not
+    # (e.g. upgrading from some version with different naming patterns)
     echo "$SVCINST_PROPS" | while read SVCINST_PROP DEVNAME_PROP ; do
         echo "$SVCINSTS" | grep -E "^${SVCINST_PROP}"'$' >/dev/null || echo "$SVCINST_PROP"
     done
 
-    # Find services which do not have saved names in props
+    # Find and report services which do *not* have saved device names in
+    # props (do not report those that have a non-trivial prop value):
+    # whether an empty value or completely absent from the list
     for SVCINST in $SVCINSTS ; do
-        echo "$SVCINST_PROPS" | grep -E "^${SVCINST_PROP}\t"'$' >/dev/null || echo "$SVCINST"
+        echo "$SVCINST_PROPS" | grep -E "^${SVCINST}${TABCHAR}"'$' >/dev/null && echo "$SVCINST"
+        echo "$SVCINST_PROPS" | grep -E "^${SVCINST}${TABCHAR}" >/dev/null || echo "$SVCINST"
     done
+    return 0
 }
 
 upsconf_getSection_content() {
@@ -1210,32 +1232,54 @@ nut_driver_enumerator_main() {
     # while the check for no new device section definitions is just boolean.
     # We can only exit quickly if both there are no changed sections and no
     # new or removed sections since last run.
-    ( [ -z "$UPSLIST_FILE" -a -z "$UPSLIST_SVCS" ] || ( \
+    { [ -z "$UPSLIST_FILE" -a -z "$UPSLIST_SVCS" ] || { \
         NEW_CHECKSUM="`upslist_checksums_unchanged "$UPSLIST_FILE" "$UPSLIST_SVCS"`" \
         && [ "${#NEW_CHECKSUM}" = 0 ] \
-        && upslist_equals "$UPSLIST_FILE" "$UPSLIST_SVCS" \
-    ) ) \
+        && upslist_equals "$UPSLIST_FILE" "$UPSLIST_SVCS" ; \
+    } ; } \
     && if [ -z "$DAEMON_SLEEP" -o "${VERBOSE_LOOP}" = yes ] ; then \
         echo "`date -u` : OK: No changes to reconcile between ${SERVICE_FRAMEWORK} service instances and device configurations in '$UPSCONF'" ; \
        fi \
     && [ "$RESTART_ALL" = no ] && return 0
 
-    if [ "${#NEW_CHECKSUM}" != 0 ]; then
+    # Check list of devices with new section contents (per checksum) as
+    # compared to older runs (stashed in service instance configurations).
+    if [ "${#NEW_CHECKSUM}" = 0 ]; then
+        if [ "${VERBOSE_LOOP}" = yes ] ; then
+            echo "`date -u` : No changes to reconcile between *contents* of ${SERVICE_FRAMEWORK} service instances and device configurations in '$UPSCONF', but the *list* of instances vs. devices seems to have changed"
+        fi
+    else
+        if [ "${VERBOSE_LOOP}" = yes ] ; then
+            echo "`date -u` : Got some changes to reconcile between ${SERVICE_FRAMEWORK} service instances and device configurations in '$UPSCONF', content checksums changed for: `echo ${NEW_CHECKSUM} | tr '\n' ' '`"
+        fi
         for UPSS in $NEW_CHECKSUM ; do
-            CURR_DRV="`upsconf_getDriver "$UPSS"`" || CURR_DRV=""
+            # NOTE: Pedantically, UPSS is a service instance name,
+            # and may be the MD5-normalized version in certain cases.
+            # For some operations below we need the original ups.conf
+            # section name for the device - the CURR_DEV value.
+            CURR_DEV="`USE_SAVEDINST=true get_device_for_service "${UPSS}"`" && [ "${#CURR_DEV}" -gt 0 ] || CURR_DEV="${UPSS}"
+            CURR_DRV="`upsconf_getDriver "${CURR_DEV}"`" || CURR_DRV=""
             DO_UNREGISTER=yes
             if [ -n "$CURR_DRV" ] ; then
                 # If reload is handled and does not complain,
                 # we are OK to proceed without re-defining
                 # and restarting the driver service instance.
-                "@DRVPATH@/$CURR_DRV" -a "$UPSS" -c reload-or-error >/dev/null 2>/dev/null \
+                if [ "${VERBOSE_LOOP}" = yes ] ; then
+                    echo "`date -u` : Reloading ${SERVICE_FRAMEWORK} service instance '${UPSS}' whose section '${CURR_DEV}' in config file has changed: calling driver program '${CURR_DRV}' for the low-level work..." >&2
+                fi
+                "@DRVPATH@/$CURR_DRV" -a "${CURR_DEV}" -c reload-or-error >/dev/null 2>/dev/null \
+                || { if [ "${VERBOSE_LOOP}" = yes ] ; then sleep 1; "@DRVPATH@/$CURR_DRV" -a "${CURR_DEV}" -c reload-or-error >&2 ; fi; } \
                 && DO_UNREGISTER=no
             fi
             if [ "$DO_UNREGISTER" = yes ] ; then
-                echo "Dropping old ${SERVICE_FRAMEWORK} service instance ${UPSS} whose section in config file has changed..." >&2
+                echo "Dropping old ${SERVICE_FRAMEWORK} service instance '${UPSS}' whose section '${CURR_DEV}' in config file has changed..." >&2
                 $hook_unregisterInstance "$UPSS"
+                # Re-registration to reconcile below should set the "saved" values
             else
-                echo "Keeping ${SERVICE_FRAMEWORK} service instance ${UPSS} whose section in config file has changed: live reload sufficed" >&2
+                echo "Keeping ${SERVICE_FRAMEWORK} service instance '${UPSS}' whose section '${CURR_DEV}' in config file has changed: live reload sufficed. Saving updated info into service properties." >&2
+                $hook_setSavedMD5 "$UPSS" "`upsconf_getSection_MD5 "${CURR_DEV}"`"
+                # TOTHINK: This is already there, else we redefine units for bigger discrepancies?
+                # $hook_setSavedDeviceName "$UPSS" "${CURR_DEV}"
             fi
         done
         upslist_readSvcs "after updating for new config section checksums"
diff --git a/scripts/upsdrvsvcctl/upsdrvsvcctl.in b/scripts/upsdrvsvcctl/upsdrvsvcctl.in
index 5fe9c82414..5079b764a7 100755
--- a/scripts/upsdrvsvcctl/upsdrvsvcctl.in
+++ b/scripts/upsdrvsvcctl/upsdrvsvcctl.in
@@ -1,6 +1,7 @@
 #!/bin/sh
 #
 # Copyright (C) 2016-2018 Eaton
+# Copyright (C) 2020-2024 Jim Klimov <jimklimov+nut@gmail.com>
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -32,17 +33,22 @@ fi
 VERB=""
 CMD=""
 CMDARG=""
-ENUMERATOR=""
+# Note: some frameworks separate the commands for acting and for reporting
+CMDREPORT=""
+CMDREPORTARG=""
 case "$SERVICE_FRAMEWORK" in
     smf) CMD="/usr/sbin/svcadm"
-        ENUMERATOR="@NUT_LIBEXECDIR@/nut-driver-enumerator.sh"
+        CMDREPORT="/usr/bin/svcs"
+        [ -n "${ENUMERATOR-}" ] && export ENUMERATOR || ENUMERATOR="@NUT_LIBEXECDIR@/nut-driver-enumerator.sh"
         ;;
     systemd) CMD="/bin/systemctl"
-        ENUMERATOR="@NUT_LIBEXECDIR@/nut-driver-enumerator.sh"
+        CMDREPORT="${CMD}"
+        [ -n "${ENUMERATOR-}" ] && export ENUMERATOR || ENUMERATOR="@NUT_LIBEXECDIR@/nut-driver-enumerator.sh"
         ;;
     *)  echo "Unrecognized SERVICE_FRAMEWORK: $SERVICE_FRAMEWORK" >&2 ; exit ;;
 esac
-
+[ -n "${UPSDRVCTL-}" ] && export UPSDRVCTL || UPSDRVCTL='@SBINDIR@/upsdrvctl'
+PACKAGE_VERSION='@PACKAGE_VERSION@'
 
 usage() {
     # Note: version header differs from UPS_VERSION in binaries that
@@ -57,6 +63,8 @@ usage: $0 [OPTIONS] (start | stop | shutdown) [<ups>]
 
 Options:
   -h            	display this help
+  -V            	display upsdrvctl binary program version (should
+                	not differ from script version above, but...)
   -t            	testing mode - prints actions without doing them
   -D            	raise debugging level
   --timeout-cmd <prog>	service management calls will be time-limited
@@ -91,6 +99,16 @@ usage: $0 [OPTIONS] list [<ups>]
                 	to list the mapping of service instances to device sections
   list <ups>    	(optionally return the service instance name for one device)
 
+usage: $0 [OPTIONS] status [<ups>]
+  status        	report run-time status for each driver in ups.conf
+                	and call $ENUMERATOR
+                	to list the mapping of service instances to device sections
+                	and report run-time status for each one that was matched
+  status <ups>  	(optionally return the status info only for one device)
+                	Fields: SVC_NAME SVC_STATE UPSNAME UPSDRV RUNNING PF_PID S_RESPONSIVE S_PID S_STATUS
+                	(SVC_* according to service management framework; and
+                	PF_* = according to PID file, if any; S_* = via socket
+                	protocol -- as defined by upsdrvctl)
 usage: $0 [OPTIONS] show-config [<ups>]
   show-config <ups>	output config section from ups.conf for device <ups>
   show-config   	...or all devices if no <ups> argument was passed
@@ -132,6 +150,86 @@ while [ $# -gt 0 ]; do
                 eval $ENUMERATOR --show-all-configs ; exit $?
             fi
             ;;
+        status)
+            RES=0
+            STATUSES="`NUT_QUIET_INIT_BANNER=true "${UPSDRVCTL}" status $2`" || RES=$?
+            if [ x"${STATUSES}" = x ]; then
+                exit $RES
+            fi
+
+            SVCINSTS="`$0 list $2`" || RES=$?
+            # Use a common approach below, even if we only got one instance name from list()
+            if [ -n "$2" ] && [ -n "${SVCINSTS}" ] ; then SVCINSTS="${SVCINSTS}	$2" ; fi
+
+            # Accomodate svc:/system/power/nut-driver:dummy (SMF)
+            # or         nut-driver@dummy.service           (systemd)
+            case "$SERVICE_FRAMEWORK" in
+                smf) SVC_NAME_WIDTH="39" ; SVC_STATE_WIDTH="11" ;;
+                systemd) SVC_NAME_WIDTH="30" ; SVC_STATE_WIDTH="23" ;;
+            esac
+
+            echo "$STATUSES" | ( COUNT=0; while IFS='' read LINE ; do
+                COUNT="`expr $COUNT + 1`"
+                if [ "$COUNT" = 1 ] ; then
+                    # Header line
+                    printf '%-'"${SVC_NAME_WIDTH}"'s\t%'"${SVC_STATE_WIDTH}"'s\t%s\n' "SVC_NAME" "SVC_STATE" "$LINE"
+                    continue
+                fi
+                DEV_NAME="`echo "$LINE" | awk '{print $1}'`"
+                SVC_NAME="`echo "$SVCINSTS" | awk '($NF == "'"${DEV_NAME}"'") {print $1}'`" && [ -n "$SVC_NAME" ] || SVC_NAME="N/A"
+                if [ x"$SVC_NAME" = "N/A" ]; then
+                    SVC_STATE="N/A"
+                else
+                    case "$SERVICE_FRAMEWORK" in
+                        smf) SVC_STATE="`$CMDREPORT -Hostate ${SVC_NAME} 2>/dev/null`" \
+                            && [ -n "$SVC_STATE" ] && [ 1 = `echo "$SVC_STATE" | wc -l` ] \
+                            || SVC_STATE="N/A"
+                            ;;
+                        systemd) SVC_STATE=""
+                            CMDRES=0
+                            OUT="`$CMDREPORT is-enabled "${SVC_NAME}" 2>/dev/null`" || CMDRES=$?
+                            if [ x"$OUT" != x ] ; then SVC_STATE="${OUT}" ; else
+                                [ 0 = "$CMDRES" ] && SVC_STATE="enabled" || SVC_STATE="disabled"
+                            fi
+                            # At this point we should have some value, so others below
+                            # may be or not be suffixed with a comma.
+
+                            # The masked unit state has no separate query in some (all?)
+                            # systemd versions and can be reported as part of the above
+                            CMDRES=0
+                            OUT="`$CMDREPORT is-masked "${SVC_NAME}" 2>/dev/null`" || CMDRES=$?
+                            if [ x"$OUT" != x ] ; then
+                                if [ x"${SVC_STATE}" != xmasked ] && [ x"${SVC_STATE}" != x"${OUT}" ] ; then
+                                    SVC_STATE="${SVC_STATE},${OUT}"
+                                fi
+                            else
+                                [ 0 = "$CMDRES" ] && SVC_STATE="${SVC_STATE},masked" || true
+                            fi
+
+                            CMDRES=0
+                            OUT="`$CMDREPORT is-active "${SVC_NAME}" 2>/dev/null`" || CMDRES=$?
+                            if [ x"$OUT" != x ] ; then
+                                SVC_STATE="${SVC_STATE},${OUT}"
+                            else
+                                [ 0 = "$CMDRES" ] && SVC_STATE="${SVC_STATE},active" || true
+                            fi
+
+                            CMDRES=0
+                            OUT="`$CMDREPORT is-failed "${SVC_NAME}" 2>/dev/null`" || CMDRES=$?
+                            if [ x"$OUT" != x ] ; then
+                                if [ x"${OUT}" != xactive ] && [ x"${OUT}" != xinactive ] ; then
+                                    SVC_STATE="${SVC_STATE},${OUT}"
+                                fi
+                            else
+                                [ 0 = "$CMDRES" ] && SVC_STATE="${SVC_STATE},failed" || true
+                            fi
+                            ;;
+                    esac
+                fi
+                printf '%-'"${SVC_NAME_WIDTH}"'s\t%'"${SVC_STATE_WIDTH}"'s\t%s\n' "$SVC_NAME" "$SVC_STATE" "$LINE"
+            done )
+            exit $RES
+            ;;
         start|stop)
             ACTION="$1"
             if [ -n "$2" ] ; then
@@ -144,7 +242,7 @@ while [ $# -gt 0 ]; do
             echo "Stopping the driver service instance(s) to release exclusive resources, if any..." >&2
             RES=0
             $0 stop $2
-            @SBINDIR@/upsdrvctl shutdown $2 || RES=$?
+            "${UPSDRVCTL}" shutdown $2 || RES=$?
             echo "Starting the driver service instance(s) so they can reconnect when the UPS returns..." >&2
             $0 start $2
             exit $RES
@@ -171,6 +269,7 @@ while [ $# -gt 0 ]; do
             ;;
         -t) DRYRUN="echo" ;;
         -h) usage; exit 0 ;;
+        -V) "${UPSDRVCTL}" -V ; exit ;;
         -D) DEBUG="`expr $DEBUG + 1`" ;;
         -r|-u) echo "Option '$1 $2' is not implemented via services currently" >&2 ; shift;;
         *)  echo "Unrecognized argument: $1" >&2 ; exit ;;
diff --git a/scripts/valgrind/.valgrind.supp b/scripts/valgrind/.valgrind.supp
new file mode 100644
index 0000000000..2e175ebaf5
--- /dev/null
+++ b/scripts/valgrind/.valgrind.supp
@@ -0,0 +1,142 @@
+{
+   <socketcall_sendto>
+   Memcheck:Param
+   socketcall.send(msg)
+   fun:send
+   ...
+}
+{
+   <glibc_freeres>
+   Memcheck:Free
+   fun:free
+   ...
+   fun:__libc_freeres
+   ...
+}
+{
+   <glibc_eh_alloc__see_bug_66339>
+   Memcheck:Leak
+   match-leak-kinds: reachable
+   fun:malloc
+   fun:pool
+   fun:__static_initialization_and_destruction_0
+   fun:_GLOBAL__sub_I_eh_alloc.cc
+   ...
+}
+{
+   <libgcrypt_init>
+   Memcheck:Leak
+   match-leak-kinds: reachable
+   fun:malloc
+   ...
+   fun:_gcry_mpi_init
+   fun:global_init
+   ...
+}
+{
+   <libssl_init_CRYPTO>
+   Memcheck:Leak
+   ...
+   fun:CRYPTO_*
+   ...
+}
+{
+   <libssl_init_SSL_CTX>
+   Memcheck:Leak
+   ...
+   fun:SSL_CTX_*
+   ...
+}
+{
+   <libssl_init_OPENSSL>
+   Memcheck:Leak
+   ...
+   fun:OPENSSL_*
+   ...
+}
+{
+   <ltdl_init>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:_dl_init
+   ...
+}
+{
+   <ltdl_init>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:_dl_new_object
+   ...
+}
+{
+   <ltdl_init>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:elf_machine_rela
+   ...
+}
+{
+   <ltdl_init>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:dl_open_worker
+   ...
+}
+{
+   <ltdl_init>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:_dlerror_run
+   ...
+}
+{
+   <nut-scanner-snmp-libinit>
+   Memcheck:Leak
+   ...
+   fun:init_snmp_once
+   ...
+}
+{
+   <nut-scanner-snmp-sess_open>
+   Memcheck:Leak
+   fun:*alloc
+   ...
+   fun:wrap_nut_snmp_sess_open
+   ...
+}
+{
+   <nut-scanner-ipmi-ctxinit>
+   Memcheck:Leak
+   ...
+   fun:wrap_nut_ipmi_ctx_create
+   ...
+}
+{
+   <nut-scanner-avahi-clientinit>
+   Memcheck:Leak
+   ...
+   fun:wrap_nut_avahi_client_new
+   ...
+}
+{
+   # https://forums.freebsd.org/threads/named-semaphore-uninitialized-bytes.84850/
+   <glibc-sem_open>
+   Memcheck:Cond
+   ...
+   fun:sem_open
+   ...
+}
+{
+   <glibc-sem_trywait>
+   Memcheck:Cond
+   ...
+   fun:sem_trywait*
+   ...
+   fun:start_thread
+   ...
+}
diff --git a/scripts/valgrind/README.adoc b/scripts/valgrind/README.adoc
new file mode 100644
index 0000000000..6d5866163e
--- /dev/null
+++ b/scripts/valgrind/README.adoc
@@ -0,0 +1,16 @@
+VALGRIND resources
+==================
+
+Helper script and suppression file to analyze NUT binaries.
+
+Example use-case:
+----
+:; make -ks -j && LD_LIBRARY_PATH=`pwd`/clients/.libs \
+    ./scripts/valgrind/valgrind.sh ./tools/nut-scanner/nut-scanner -DDDDDD -m auto
+----
+
+See also:
+
+* link:https://wiki.wxwidgets.org/Valgrind_Suppression_File_Howto[Valgrind Suppression File How-to]
+  - Notably, add `--gen-suppressions=all --error-limit=no` to `valgrind`
+    program options to generate suppression snippets
diff --git a/scripts/valgrind/valgrind.sh b/scripts/valgrind/valgrind.sh
new file mode 100755
index 0000000000..2bb8608125
--- /dev/null
+++ b/scripts/valgrind/valgrind.sh
@@ -0,0 +1,21 @@
+#!/bin/sh
+
+# Copyright (C) 2024 by Jim Klimov <jimklimov+nut@gmail.com>
+
+SCRIPTDIR="`dirname "$0"`"
+SCRIPTDIR="`cd "$SCRIPTDIR" && pwd`"
+
+LTEXEC=""
+[ -n "${LIBTOOL-}" ] || LIBTOOL="`command -v libtool`" 2>/dev/null
+[ -z "${LIBTOOL}"  ] || LTEXEC="${LIBTOOL} --mode=execute "
+
+# TODO: Also wrap tool=callgrind e.g. via $0 symlink name?
+
+exec ${LTEXEC} \
+valgrind \
+	--tool=memcheck --verbose \
+	--leak-check=full --show-reachable=yes --error-exitcode=1 --show-error-list=yes \
+	--trace-children=yes --track-fds=yes --show-leak-kinds=all --track-origins=yes \
+	--suppressions="${SCRIPTDIR}/.valgrind.supp" \
+	${VALGRIND_OPTIONS-} \
+	"$@"
diff --git a/server/Makefile.am b/server/Makefile.am
index 878f16f588..f3dcf60ac2 100644
--- a/server/Makefile.am
+++ b/server/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 # Make sure out-of-dir dependencies exist (especially when dev-building parts):
 $(top_builddir)/common/libcommon.la \
diff --git a/server/netget.c b/server/netget.c
index c2a31fa354..1fd4d2475a 100644
--- a/server/netget.c
+++ b/server/netget.c
@@ -157,18 +157,49 @@ static void get_type(nut_ctype_t *client, const char *upsname, const char *var)
 	/* Any variable that is not string | range | enum is just a simple
 	 * numeric value */
 
+	if (!(node->flags & ST_FLAG_NUMBER)) {
+		upsdebugx(3, "%s: assuming that UPS[%s] variable %s which has no type flag is a NUMBER",
+			__func__, upsname, var);
+	}
+
 	sendback(client, "%s NUMBER\n", buf);
 }
 
 static void get_var_server(nut_ctype_t *client, const char *upsname, const char *var)
 {
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+	int	pkgurlHasNutOrg = PACKAGE_URL ? (strstr(PACKAGE_URL, "networkupstools.org") != NULL) : 0;
+
 	if (!strcasecmp(var, "server.info")) {
+		/* NOTE: Some compilers deduce that macro-based decisions about
+		 * NUT_VERSION_IS_RELEASE make one of codepaths unreachable in
+		 * a particular build. So we pragmatically handwave this away.
+		 */
 		sendback(client, "VAR %s server.info "
 			"\"Network UPS Tools upsd %s - "
-			"https://www.networkupstools.org/\"\n",
-			upsname, UPS_VERSION);
+			"%s%s%s\"\n",
+			upsname, UPS_VERSION,
+			PACKAGE_URL ? PACKAGE_URL : "",
+			(PACKAGE_URL && !pkgurlHasNutOrg) ? " or " : "",
+			pkgurlHasNutOrg ? "" : "https://www.networkupstools.org/"
+			);
 		return;
 	}
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
 
 	if (!strcasecmp(var, "server.version")) {
 		sendback(client, "VAR %s server.version \"%s\"\n",
diff --git a/server/netmisc.c b/server/netmisc.c
index ec4e8d28df..fbf8e0eb31 100644
--- a/server/netmisc.c
+++ b/server/netmisc.c
@@ -31,14 +31,46 @@
 
 void net_ver(nut_ctype_t *client, size_t numarg, const char **arg)
 {
+	int	pkgurlHasNutOrg = 0;
 	NUT_UNUSED_VARIABLE(arg);
+
 	if (numarg != 0) {
 		send_err(client, NUT_ERR_INVALID_ARGUMENT);
 		return;
 	}
 
-	sendback(client, "Network UPS Tools upsd %s - https://www.networkupstools.org/\n",
-		UPS_VERSION);
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+	if (PACKAGE_URL && strstr(PACKAGE_URL, "networkupstools.org")) {
+		pkgurlHasNutOrg = 1;
+	} else {
+		upsdebugx(1, "%s: WARNING: PACKAGE_URL of this build does not point to networkupstools.org!", __func__);
+	}
+
+	/* NOTE: Some compilers deduce that macro-based decisions about
+	 * NUT_VERSION_IS_RELEASE make one of codepaths unreachable in
+	 * a particular build. So we pragmatically handwave this away.
+	 */
+	sendback(client, "Network UPS Tools upsd %s - %s%s%s\n",
+		UPS_VERSION,
+		PACKAGE_URL ? PACKAGE_URL : "",
+		(PACKAGE_URL && !pkgurlHasNutOrg) ? " or " : "",
+		pkgurlHasNutOrg ? "" : "https://www.networkupstools.org/"
+		);
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
 }
 
 void net_netver(nut_ctype_t *client, size_t numarg, const char **arg)
@@ -60,8 +92,9 @@ void net_help(nut_ctype_t *client, size_t numarg, const char **arg)
 		return;
 	}
 
-	sendback(client, "Commands: HELP VER GET LIST SET INSTCMD LOGIN LOGOUT"
-		" USERNAME PASSWORD STARTTLS\n");
+	sendback(client, "Commands: HELP VER PROTVER GET LIST SET INSTCMD"
+		" LOGIN LOGOUT USERNAME PASSWORD STARTTLS\n");
+	/* Not exposed: PRIMARY/MASTER FSD */
 }
 
 void net_fsd(nut_ctype_t *client, size_t numarg, const char **arg)
diff --git a/server/netset.c b/server/netset.c
index 1e185b86d7..bd5f033a2e 100644
--- a/server/netset.c
+++ b/server/netset.c
@@ -56,12 +56,19 @@ static void set_var(nut_ctype_t *client, const char *upsname, const char *var,
 	val = sstate_getinfo(ups, var);
 
 	if (!val) {
+		/* Technically, this includes state tree entries
+		 * with a defined name but null value so far.
+		 * FIXME? Use sstate_getnode() to differentiate
+		 *  the cases? Any practical use for this?
+		 */
 		send_err(client, NUT_ERR_VAR_NOT_SUPPORTED);
 		return;
 	}
 
 	/* make sure this variable is writable (RW) */
 	if ((sstate_getflags(ups, var) & ST_FLAG_RW) == 0) {
+		upsdebugx(3, "%s: UPS [%s]: value of %s is read-only",
+			__func__, ups->name, var);
 		send_err(client, NUT_ERR_READONLY);
 		return;
 	}
@@ -87,6 +94,8 @@ static void set_var(nut_ctype_t *client, const char *upsname, const char *var,
 		 * even on architectures with a moderate INTMAX
 		 */
 		if (aux < (int) strlen(newval)) {
+			upsdebugx(3, "%s: UPS [%s]: Not a value fitting in STRING:%ld %s: %s",
+				__func__, ups->name, aux, var, newval);
 			send_err(client, NUT_ERR_TOO_LONG);
 			return;
 		}
@@ -109,6 +118,9 @@ static void set_var(nut_ctype_t *client, const char *upsname, const char *var,
 		}
 
 		if (!found) {
+			/* Not a value known in the pre-defined enumeration */
+			upsdebugx(3, "%s: UPS [%s]: Not a value known in ENUM %s: %s",
+				__func__, ups->name, var, newval);
 			send_err(client, NUT_ERR_INVALID_VALUE);
 			return;
 		}
@@ -132,6 +144,9 @@ static void set_var(nut_ctype_t *client, const char *upsname, const char *var,
 		}
 
 		if (!found) {
+			/* Not in range */
+			upsdebugx(3, "%s: UPS [%s]: Not a value fitting in RANGE %s: %s",
+				__func__, ups->name, var, newval);
 			send_err(client, NUT_ERR_INVALID_VALUE);
 			return;
 		}
diff --git a/server/netssl.c b/server/netssl.c
index d92fb1ba89..5a865284c3 100644
--- a/server/netssl.c
+++ b/server/netssl.c
@@ -40,19 +40,19 @@
 #include "nut_stdint.h"
 
 #ifdef WITH_NSS
-	#include <pk11pub.h>
-	#include <prinit.h>
-	#include <private/pprio.h>
+#	include <pk11pub.h>
+#	include <prinit.h>
+#	include <private/pprio.h>
 #if defined(NSS_VMAJOR) && (NSS_VMAJOR > 3 || (NSS_VMAJOR == 3 && defined(NSS_VMINOR) && NSS_VMINOR >= 39))
-	#include <keyhi.h>
-	#include <keythi.h>
+#	include <keyhi.h>
+#	include <keythi.h>
 #else
-	#include <key.h>
-	#include <keyt.h>
+#	include <key.h>
+#	include <keyt.h>
 #endif /* NSS before 3.39 */
-	#include <secerr.h>
-	#include <sslerr.h>
-	#include <sslproto.h>
+#	include <secerr.h>
+#	include <sslerr.h>
+#	include <sslproto.h>
 #endif /* WITH_NSS */
 
 char	*certfile = NULL;
@@ -346,6 +346,8 @@ void net_starttls(nut_ctype_t *client, size_t numarg, const char **arg)
 		upslog_with_errno(LOG_ERR, "Unknown return value from SSL_accept");
 		ssl_error(client->ssl, ret);
 		break;
+	default:
+		break;
 	}
 
 #elif defined(WITH_NSS) /* WITH_OPENSSL */
diff --git a/server/nut_ctype.h b/server/nut_ctype.h
index 25cead0754..55ce735220 100644
--- a/server/nut_ctype.h
+++ b/server/nut_ctype.h
@@ -27,14 +27,14 @@
 
 /* Mozilla NSS */
 #ifdef WITH_NSS
-	#include <nss.h>
-	#include <ssl.h>
+#	include <nss.h>
+#	include <ssl.h>
 #endif
 
 /* OpenSSL */
 #ifdef WITH_OPENSSL
-	#include <openssl/err.h>
-	#include <openssl/ssl.h>
+#	include <openssl/err.h>
+#	include <openssl/ssl.h>
 #endif
 
 #include "parseconf.h"
diff --git a/server/sockdebug.c b/server/sockdebug.c
index a86868b6bc..2f0679811d 100644
--- a/server/sockdebug.c
+++ b/server/sockdebug.c
@@ -123,6 +123,9 @@ static void read_sock(int fd)
 			case -1:
 				printf("Parse error: [%s]\n", sock_ctx.errmsg);
 				break;
+
+			default:
+				break;
 		}
 	}
 }
diff --git a/server/sstate.c b/server/sstate.c
index 5da0834e29..e335bd4e25 100644
--- a/server/sstate.c
+++ b/server/sstate.c
@@ -45,24 +45,24 @@ static int parse_args(upstype_t *ups, size_t numargs, char **arg)
 		return 0;
 
 	if (!strcasecmp(arg[0], "PONG")) {
-		upsdebugx(3, "Got PONG from UPS [%s]", ups->name);
+		upsdebugx(3, "%s: Got PONG from UPS [%s]", __func__, ups->name);
 		return 1;
 	}
 
 	if (!strcasecmp(arg[0], "DUMPDONE")) {
-		upsdebugx(3, "UPS [%s]: dump is done", ups->name);
+		upsdebugx(3, "%s: UPS [%s]: dump is done", __func__, ups->name);
 		ups->dumpdone = 1;
 		return 1;
 	}
 
 	if (!strcasecmp(arg[0], "DATASTALE")) {
-		upsdebugx(3, "UPS [%s]: data is STALE now", ups->name);
+		upsdebugx(3, "%s: UPS [%s]: data is STALE now", __func__, ups->name);
 		ups->data_ok = 0;
 		return 1;
 	}
 
 	if (!strcasecmp(arg[0], "DATAOK")) {
-		upsdebugx(3, "UPS [%s]: data is NOT STALE now", ups->name);
+		upsdebugx(3, "%s: UPS [%s]: data is NOT STALE now", __func__, ups->name);
 		ups->data_ok = 1;
 		return 1;
 	}
@@ -125,7 +125,7 @@ static int parse_args(upstype_t *ups, size_t numargs, char **arg)
 	/* TRACKING <id> <status> */
 	if (!strcasecmp(arg[0], "TRACKING")) {
 		tracking_set(arg[1], arg[2]);
-		upsdebugx(1, "TRACKING: ID %s status %s", arg[1], arg[2]);
+		upsdebugx(1, "%s: TRACKING: ID %s status %s", __func__, arg[1], arg[2]);
 
 		/* log actual result of instcmd / setvar */
 		if (strncmp(arg[2], "PENDING", 7) != 0) {
@@ -163,7 +163,7 @@ static void sendping(upstype_t *ups)
 		return;
 	}
 
-	upsdebugx(3, "Pinging UPS [%s]", ups->name);
+	upsdebugx(3, "%s: Pinging UPS [%s]", __func__, ups->name);
 
 #ifndef WIN32
 	ret = write(ups->sock_fd, cmd, cmdlen);
@@ -239,7 +239,7 @@ TYPE_FD sstate_connect(upstype_t *ups)
 	ret = fcntl(fd, F_GETFL, 0);
 
 	if (ret < 0) {
-		upslog_with_errno(LOG_ERR, "fcntl get on UPS [%s] failed", ups->name);
+		upslog_with_errno(LOG_ERR, "%s: fcntl get on UPS [%s] failed", __func__, ups->name);
 		close(fd);
 		return ERROR_FD;
 	}
@@ -247,7 +247,7 @@ TYPE_FD sstate_connect(upstype_t *ups)
 	ret = fcntl(fd, F_SETFL, ret | O_NDELAY);
 
 	if (ret < 0) {
-		upslog_with_errno(LOG_ERR, "fcntl set O_NDELAY on UPS [%s] failed", ups->name);
+		upslog_with_errno(LOG_ERR, "%s: fcntl set O_NDELAY on UPS [%s] failed", __func__, ups->name);
 		close(fd);
 		return ERROR_FD;
 	}
@@ -449,7 +449,7 @@ int sstate_dead(upstype_t *ups, int arg_maxage)
 
 	/* an unconnected ups is always dead */
 	if ((!ups) || INVALID_FD(ups->sock_fd)) {
-		upsdebugx(3, "sstate_dead: connection to driver socket for UPS [%s] lost", ups->name);
+		upsdebugx(3, "%s: connection to driver socket for UPS [%s] lost", __func__, ups->name);
 		return 1;	/* dead */
 	}
 
@@ -464,14 +464,14 @@ int sstate_dead(upstype_t *ups, int arg_maxage)
 		sendping(ups);
 
 	if (elapsed > arg_maxage) {
-		upsdebugx(3, "sstate_dead: didn't hear from driver for UPS [%s] for %g seconds (max %d)",
-					ups->name, elapsed, arg_maxage);
+		upsdebugx(3, "%s: didn't hear from driver for UPS [%s] for %g seconds (max %d)",
+			__func__, ups->name, elapsed, arg_maxage);
 		return 1;	/* dead */
 	}
 
 	/* ignore DATAOK/DATASTALE unless the dump is done */
 	if ((ups->dumpdone) && (!ups->data_ok)) {
-		upsdebugx(3, "sstate_dead: driver for UPS [%s] says data is stale", ups->name);
+		upsdebugx(3, "%s: driver for UPS [%s] says data is stale", __func__, ups->name);
 		return 1;	/* dead */
 	}
 
diff --git a/server/upsd.c b/server/upsd.c
index bd3a1543f7..6a7f67a413 100644
--- a/server/upsd.c
+++ b/server/upsd.c
@@ -5,6 +5,7 @@
 	2008		Arjen de Korte <adkorte-guest@alioth.debian.org>
 	2011 - 2012	Arnaud Quette <arnaud.quette.free.fr>
 	2019 		Eaton (author: Arnaud Quette <ArnaudQuette@eaton.com>)
+	2020 - 2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -191,6 +192,8 @@ upstype_t *get_ups_ptr(const char *name)
 	upstype_t	*tmp;
 
 	if (!name) {
+		upsdebugx(3, "%s: not a valid UPS: <null>",
+			__func__);
 		return NULL;
 	}
 
@@ -200,6 +203,8 @@ upstype_t *get_ups_ptr(const char *name)
 		}
 	}
 
+	upsdebugx(3, "%s: not a valid UPS: %s",
+		__func__, NUT_STRARG(name));
 	return NULL;
 }
 
@@ -460,10 +465,12 @@ static void setuptcp(stype_t *server)
 			fatal_with_errno(EXIT_FAILURE, "setuptcp: setsockopt");
 		}
 
+#ifdef IPV6_V6ONLY
 		/* Ordinarily we request that IPv6 listeners handle only IPv6
 		 * and not IPv4 mapped addresses - if the OS would honour that.
 		 * TOTHINK: Does any platform need `#ifdef IPV6_V6ONLY` given
 		 * that we apparently already have AF_INET6 OS support everywhere?
+		 * YES: Solaris 8 has IPv6 but not this symbol.
 		 */
 		if (ai->ai_family == AF_INET6) {
 			if (setsockopt(sock_fd, IPPROTO_IPV6, IPV6_V6ONLY, (void *)&one, sizeof(one)) != 0) {
@@ -471,6 +478,7 @@ static void setuptcp(stype_t *server)
 				/* ack, ignore */
 			}
 		}
+#endif
 
 		if (bind(sock_fd, ai->ai_addr, ai->ai_addrlen) < 0) {
 			upsdebug_with_errno(3, "setuptcp: bind");
@@ -1088,6 +1096,8 @@ static void driver_free(void)
 
 static void upsd_cleanup(void)
 {
+	upsdebugx(1, "%s: starting the end-game", __func__);
+
 	if (strlen(pidfn) > 0) {
 		unlink(pidfn);
 	}
@@ -1117,6 +1127,8 @@ static void upsd_cleanup(void)
 		CloseHandle(mutex);
 	}
 #endif
+
+	upsdebugx(1, "%s: finished", __func__);
 }
 
 static void poll_reload(void)
@@ -1311,6 +1323,8 @@ char *tracking_get(const char *id)
 			return "ERR INVALID-ARGUMENT";
 		case STAT_FAILED:
 			return "ERR FAILED";
+		default:
+			break;
 		}
 	}
 
@@ -1799,9 +1813,10 @@ static void help(const char *arg_progname)
 
 static void help(const char *arg_progname)
 {
-	printf("Network server for UPS data.\n\n");
-	printf("usage: %s [OPTIONS]\n", arg_progname);
+	print_banner_once(arg_progname, 2);
+	printf("NUT network data server for UPS monitoring and management.\n");
 
+	printf("\nusage: %s [OPTIONS]\n", arg_progname);
 	printf("\n");
 	printf("  -c <command>	send <command> via signal to background process\n");
 	printf("		commands:\n");
@@ -1875,7 +1890,7 @@ void check_perms(const char *fn)
 
 	/* include the x bit here in case we check a directory */
 	if (st.st_mode & (S_IROTH | S_IXOTH)) {
-		upslogx(LOG_WARNING, "%s is world readable", fn);
+		upslogx(LOG_WARNING, "WARNING: %s is world readable (hope you don't have passwords there)", fn);
 	}
 #else
 	NUT_UNUSED_VARIABLE(fn);
@@ -1923,7 +1938,7 @@ int main(int argc, char **argv)
 	/* set up some things for later */
 	snprintf(pidfn, sizeof(pidfn), "%s/%s.pid", altpidpath(), progname);
 
-	printf("Network UPS Tools %s %s\n", progname, UPS_VERSION);
+	print_banner_once(progname, 0);
 
 	while ((i = getopt(argc, argv, "+h46p:qr:i:fu:Vc:P:DFB")) != -1) {
 		switch (i) {
@@ -1949,9 +1964,10 @@ int main(int argc, char **argv)
 				break;
 
 			case 'V':
-				/* Note - we already printed the banner for program name */
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(progname, 1);
 				nut_report_config_flags();
-
 				exit(EXIT_SUCCESS);
 
 			case 'c':
@@ -2031,20 +2047,22 @@ int main(int argc, char **argv)
 	 * for probing whether a competing older instance of this program
 	 * is running (error if it is).
 	 */
+	/* Hush the fopen(pidfile) message but let "real errors" be seen */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_KILL_SIG0PING - 1;
 #ifndef WIN32
 	/* If cmd == 0 we are starting and check if a previous instance
 	 * is running by sending signal '0' (i.e. 'kill <pid> 0' equivalent)
 	 */
 
 	if (oldpid < 0) {
-		cmdret = sendsignalfn(pidfn, cmd);
+		cmdret = sendsignalfn(pidfn, cmd, progname, 1);
 	} else {
-		cmdret = sendsignalpid(oldpid, cmd);
+		cmdret = sendsignalpid(oldpid, cmd, progname, 1);
 	}
 #else	/* if WIN32 */
 	if (cmd) {
 		/* Command the running daemon, it should be there */
-		cmdret = sendsignal(UPSD_PIPE_NAME, cmd);
+		cmdret = sendsignal(UPSD_PIPE_NAME, cmd, 1);
 	} else {
 		/* Starting new daemon, check for competition */
 		mutex = CreateMutex(NULL, TRUE, UPSD_PIPE_NAME);
@@ -2084,7 +2102,7 @@ int main(int argc, char **argv)
 		 */
 		upslogx(LOG_WARNING, "Could not %s PID file '%s' "
 			"to see if previous upsd instance is "
-			"already running!",
+			"already running or not!",
 			(cmdret == -3 ? "find" : "parse"),
 			pidfn);
 		break;
@@ -2138,6 +2156,9 @@ int main(int argc, char **argv)
 		exit((cmdret == 0) ? EXIT_SUCCESS : EXIT_FAILURE);
 	}
 
+	/* Restore the signal errors verbosity */
+	nut_sendsignal_debug_level = NUT_SENDSIGNAL_DEBUG_LEVEL_DEFAULT;
+
 	argc -= optind;
 	argv += optind;
 
diff --git a/server/upsd.h b/server/upsd.h
index dfe27140ae..a6b96adce8 100644
--- a/server/upsd.h
+++ b/server/upsd.h
@@ -25,7 +25,7 @@
  */
 
 #ifndef UPSD_H_SEEN
-#define UPSD_H_SEEN
+#define UPSD_H_SEEN 1
 
 #include "attribute.h"
 
diff --git a/tests/.gitignore b/tests/.gitignore
index 876e375e29..ab9969c713 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -16,6 +16,12 @@
 /nuttimetest
 /nuttimetest.log
 /nuttimetest.trs
+/nutbooltest
+/nutbooltest.log
+/nutbooltest.trs
+/getexponenttest-belkin-hid
+/getexponenttest-belkin-hid.log
+/getexponenttest-belkin-hid.trs
 /getvaluetest
 /getvaluetest.log
 /getvaluetest.trs
diff --git a/tests/Makefile.am b/tests/Makefile.am
index d7a1cd9ccc..47531ba8ce 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 SUBDIRS = . NIT
 
@@ -16,6 +16,7 @@ all: $(TESTS)
 EXTRA_DIST = nut-driver-enumerator-test.sh nut-driver-enumerator-test--ups.conf
 
 TESTS =
+noinst_LTLIBRARIES =
 CLEANFILES = *.trs *.log
 
 AM_CFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/drivers
@@ -56,6 +57,10 @@ TESTS += nuttimetest
 nuttimetest_SOURCES = nuttimetest.c
 nuttimetest_LDADD = $(top_builddir)/common/libcommon.la
 
+TESTS += nutbooltest
+nutbooltest_SOURCES = nutbooltest.c
+#nutbooltest_LDADD = $(top_builddir)/common/libcommon.la
+
 # Separate the .deps of other dirs from this one
 LINKED_SOURCE_FILES = hidparser.c
 
@@ -65,7 +70,19 @@ hidparser.c: $(top_srcdir)/drivers/hidparser.c
 	test -s "$@" || ln -s -f "$(top_srcdir)/drivers/hidparser.c" "$@"
 
 if WITH_USB
-TESTS += getvaluetest
+TESTS += getvaluetest getexponenttest-belkin-hid
+
+# We only need to call a few methods, not use the whole source - so
+# not linking it as a getvaluetest_SOURCE file (has too many deps):
+noinst_LTLIBRARIES += libdriverstubusb.la
+nodist_libdriverstubusb_la_SOURCES = driver-stub-usb.c
+libdriverstubusb_la_CFLAGS = $(AM_CFLAGS) $(LIBUSB_CFLAGS)
+#libdriverstubusb_la_LIBADD = $(top_builddir)/common/libcommon.la
+
+getexponenttest-belkin-hid.c: $(top_srcdir)/drivers/belkin-hid.c
+getexponenttest_belkin_hid_SOURCES = getexponenttest-belkin-hid.c
+getexponenttest_belkin_hid_CFLAGS = $(AM_CFLAGS) $(LIBUSB_CFLAGS)
+getexponenttest_belkin_hid_LDADD = $(top_builddir)/common/libcommon.la libdriverstubusb.la
 
 getvaluetest_SOURCES = getvaluetest.c
 nodist_getvaluetest_SOURCES = hidparser.c
@@ -75,6 +92,7 @@ getvaluetest_LDADD = $(top_builddir)/common/libcommon.la
 else !WITH_USB
 EXTRA_DIST += getvaluetest.c hidparser.c
 endif !WITH_USB
+EXTRA_DIST += driver-stub-usb.c
 
 if WITH_GPIO
 TESTS += gpiotest
@@ -101,6 +119,7 @@ EXTRA_DIST += generic_gpio_utest.h generic_gpio_test.txt
 # Make sure out-of-dir dependencies exist (especially when dev-building parts):
 $(top_builddir)/drivers/libdummy_mockdrv.la \
 $(top_builddir)/common/libnutconf.la \
+$(top_builddir)/common/libcommonclient.la \
 $(top_builddir)/common/libcommon.la: dummy
 	+@cd $(@D) && $(MAKE) $(AM_MAKEFLAGS) $(@F)
 
@@ -128,7 +147,7 @@ check_PROGRAMS += cppnit
 
 if WITH_VALGRIND
 check-local: $(check_PROGRAMS)
-	RES=0; for P in $^ ; do $(VALGRIND) ./$$P || { RES=$$? ; echo "FAILED: $(VALGRIND) ./$$P" >&2; }; done; exit $$RES
+	RES=0; for P in $? ; do $(VALGRIND) ./$$P || { RES=$$? ; echo "FAILED: $(VALGRIND) ./$$P" >&2; }; done; exit $$RES
 endif WITH_VALGRIND
 
 cppunittest_CXXFLAGS = $(AM_CXXFLAGS) $(CPPUNIT_CFLAGS) $(CPPUNIT_CXXFLAGS) $(CPPUNIT_NUT_CXXFLAGS) $(CXXFLAGS)
diff --git a/tests/NIT/Makefile.am b/tests/NIT/Makefile.am
index 086519757e..069825355f 100644
--- a/tests/NIT/Makefile.am
+++ b/tests/NIT/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 EXTRA_DIST = nit.sh README.adoc
 
@@ -26,17 +26,29 @@ check-NIT: $(abs_srcdir)/nit.sh
 # Make sure pre-requisites for NIT are fresh as we iterate
 check-NIT-devel: $(abs_srcdir)/nit.sh
 	+@cd .. && ( $(MAKE) $(AM_MAKEFLAGS) -s cppnit$(EXEEXT) || echo "OPTIONAL C++ test client test will be skipped" )
-	+@cd "$(top_builddir)/clients" && $(MAKE) $(AM_MAKEFLAGS) -s upsc$(EXEEXT) upsrw$(EXEEXT) upsmon$(EXEEXT)
-	+@cd "$(top_builddir)/server" && $(MAKE) $(AM_MAKEFLAGS) -s upsd$(EXEEXT)
-	+@cd "$(top_builddir)/drivers" && $(MAKE) $(AM_MAKEFLAGS) -s dummy-ups$(EXEEXT)
+	+@cd "$(top_builddir)/clients" && $(MAKE) $(AM_MAKEFLAGS) -s upsc$(EXEEXT) upscmd$(EXEEXT) upsrw$(EXEEXT) upsmon$(EXEEXT)
+	+@cd "$(top_builddir)/server" && $(MAKE) $(AM_MAKEFLAGS) -s upsd$(EXEEXT) sockdebug$(EXEEXT)
+	+@cd "$(top_builddir)/drivers" && $(MAKE) $(AM_MAKEFLAGS) -s dummy-ups$(EXEEXT) upsdrvctl$(EXEEXT)
 	+@$(MAKE) $(AM_MAKEFLAGS) check-NIT
 
+check-NIT-sandbox: $(abs_srcdir)/nit.sh
+	[ -n "$${DEBUG_SLEEP-}" ] && [ "$${DEBUG_SLEEP-}" -gt 0 ] || DEBUG_SLEEP=600 ; export DEBUG_SLEEP ; \
+	LANG=C LC_ALL=C TZ=UTC \
+	NUT_PORT=12345 NIT_CASE=testcase_sandbox_start_drivers_after_upsd NUT_FOREGROUND_WITH_PID=true \
+	"$(abs_srcdir)/nit.sh"
+
+check-NIT-sandbox-devel: $(abs_srcdir)/nit.sh
+	+[ -n "$${DEBUG_SLEEP-}" ] && [ "$${DEBUG_SLEEP-}" -gt 0 ] || DEBUG_SLEEP=600 ; export DEBUG_SLEEP ; \
+	LANG=C LC_ALL=C TZ=UTC \
+	NUT_PORT=12345 NIT_CASE=testcase_sandbox_start_drivers_after_upsd NUT_FOREGROUND_WITH_PID=true \
+	$(MAKE) $(AM_MAKEFLAGS) check-NIT-devel
+
 SPELLCHECK_SRC = README.adoc
 
 # NOTE: Due to portability, we do not use a GNU percent-wildcard extension.
 # We also have to export some variables that may be tainted by relative
 # paths when parsing the other makefile (e.g. MKDIR_P that may be defined
-# via expanded $(top_builddir)/install_sh):
+# via expanded $(top_builddir)/install-sh):
 #%-spellchecked: % Makefile.am $(top_srcdir)/docs/Makefile.am $(abs_srcdir)/$(NUT_SPELL_DICT)
 #	+$(MAKE) -s -f $(top_builddir)/docs/Makefile $(AM_MAKEFLAGS) MKDIR_P="$(MKDIR_P)" builddir="$(builddir)" srcdir="$(srcdir)" top_builddir="$(top_builddir)" top_srcdir="$(top_srcdir)" SPELLCHECK_SRC_ONE="$<" SPELLCHECK_SRCDIR="$(srcdir)" SPELLCHECK_BUILDDIR="$(builddir)" $@
 
diff --git a/tests/NIT/README.adoc b/tests/NIT/README.adoc
index b442f27434..05be5a2d46 100644
--- a/tests/NIT/README.adoc
+++ b/tests/NIT/README.adoc
@@ -16,3 +16,20 @@ link:https://code.edge.launchpad.net/qa-regression-testing[Ubuntu QA Regression
 and link:https://salsa.debian.org/debian/nut/-/tree/debian/debian/tests[Debian packaging recipe]
 doing a similar job with NUT installed from packages and configuring
 it via files in standard path names.
+
+A sandbox prepared by this script can be used for `upsmon` testing:
+
+````
+:; make check-NIT-sandbox-devel &
+
+# Wait for sandbox, e.g. test that "${NUT_CONFPATH}/NIT.env-sandbox-ready"
+# file appeared; then source the envvars, e.g.:
+:; sleep 5 ; while ! [ -e ./tests/NIT/tmp/etc/NIT.env-sandbox-ready ] ; do sleep 1 ; done
+:; . ./tests/NIT/tmp/etc/NIT.env
+
+# Prepare upsmon.conf there, e.g.:
+:; printf 'MINSUPPLIES 1\nPOWERDOWNFLAG "%s/killpower"\nSHUTDOWNCMD "date >> \"%s/nut-shutdown.log\""\nMONITOR "%s@127.0.0.1:%s" 1 "%s" "%s" primary\n' \
+    "$NUT_STATEPATH" "$NUT_STATEPATH" 'dummy' "$NUT_PORT" \
+    'dummy-admin' "${TESTPASS_UPSMON_PRIMARY}" \
+    > "${NUT_CONFPATH}/upsmon.conf"
+````
diff --git a/tests/NIT/nit.sh b/tests/NIT/nit.sh
index 611c1d2eed..0d04dd54e3 100755
--- a/tests/NIT/nit.sh
+++ b/tests/NIT/nit.sh
@@ -8,6 +8,8 @@
 # but could be refactored for better maintainability and generic
 # approach. Part of the goal was to let this script set up the
 # sandbox to run tests which could be defined in other files.
+# To speed up this practical developer-testing aspect, you can just
+# `make check-NIT-sandbox{,-devel}` (optionally with custom DEBUG_SLEEP).
 #
 # WARNING: Current working directory when starting the script should be
 # the location where it may create temporary data (e.g. the BUILDDIR).
@@ -16,16 +18,37 @@
 #	DEBUG_SLEEP=60	to sleep after tests, with driver+server running
 #	NUT_DEBUG_MIN=3	to set (minimum) debug level for drivers, upsd...
 #	NUT_PORT=12345	custom port for upsd to listen and clients to query
+#	NUT_FOREGROUND_WITH_PID=true	default foregrounding is without
+#			PID files, this option tells daemons to save them
+#	TESTDIR=/tmp/nut-NIT	to propose a location for "etc" and "run"
+#			mock locations (under some circumstances, the
+#			script can anyway choose to `mktemp` another)
+#
+# Common sandbox run for testing goes from NUT root build directory like:
+#	DEBUG_SLEEP=600 NUT_PORT=12345 NIT_CASE=testcase_sandbox_start_drivers_after_upsd NUT_FOREGROUND_WITH_PID=true make check-NIT &
 #
 # Design note: written with dumbed-down POSIX shell syntax, to
 # properly work in whatever different OSes have (bash, dash,
 # ksh, busybox sh...)
 #
 # Copyright
-#	2022-2023 Jim Klimov <jimklimov+nut@gmail.com>
+#	2022-2024 Jim Klimov <jimklimov+nut@gmail.com>
 #
 # License: GPLv2+
 
+if [ -z "${BASH_VERSION-}" ] \
+&& (command -v bash) \
+&& [ x"${DEBUG_NONBASH-}" != xtrue ] \
+; then
+    # FIXME: detect and pass -x/-v options?
+    echo "WARNING: Re-execing in BASH (export DEBUG_NONBASH=true to avoid)" >&2
+    exec bash $0 "$@"
+fi
+
+if [ -n "${BASH_VERSION-}" ]; then
+    eval `echo "set -o pipefail"`
+fi
+
 TZ=UTC
 LANG=C
 LC_ALL=C
@@ -37,9 +60,22 @@ export NUT_QUIET_INIT_SSL
 NUT_QUIET_INIT_UPSNOTIFY="true"
 export NUT_QUIET_INIT_UPSNOTIFY
 
+# Avoid noise in syslog and OS console
+NUT_DEBUG_SYSLOG="stderr"
+export NUT_DEBUG_SYSLOG
+
 NUT_DEBUG_PID="true"
 export NUT_DEBUG_PID
 
+# Just keep upsdrvctl quiet if used in test builds or with the sandbox
+NUT_QUIET_INIT_NDE_WARNING="true"
+export NUT_QUIET_INIT_NDE_WARNING
+
+ARG_FG="-F"
+if [ x"${NUT_FOREGROUND_WITH_PID-}" = xtrue ] ; then ARG_FG="-FF" ; fi
+
+TABCHAR="`printf '\t'`"
+
 log_separator() {
     echo "" >&2
     echo "================================" >&2
@@ -87,7 +123,7 @@ isBusy_NUT_PORT() {
     [ -n "${NUT_PORT}" ] || return
 
     log_debug "isBusy_NUT_PORT() Trying to report if NUT_PORT=${NUT_PORT} is used"
-    if [ -e /proc/net/tcp ] || [ -e /proc/net/tcp6 ]; then
+    if [ -r /proc/net/tcp ] || [ -r /proc/net/tcp6 ]; then
         # Assume Linux - hex-encoded
         # IPv4:
         #   sl  local_address rem_address   st tx_queue rx_queue tr tm->when retrnsmt   uid  timeout inode
@@ -107,7 +143,7 @@ isBusy_NUT_PORT() {
         return 1
     fi
 
-    (netstat -an || sockstat -l || ss -tn || ss -n) 2>/dev/null | grep -E "[:.]${NUT_PORT}(\t| |\$)" > /dev/null \
+    (netstat -an || sockstat -l || ss -tn || ss -n) 2>/dev/null | grep -E "[:.]${NUT_PORT}(${TABCHAR}| |\$)" > /dev/null \
     && log_debug "isBusy_NUT_PORT() found that NUT_PORT=${NUT_PORT} is busy per netstat, sockstat or ss" \
     && return
 
@@ -115,13 +151,6 @@ isBusy_NUT_PORT() {
     && log_debug "isBusy_NUT_PORT() found that NUT_PORT=${NUT_PORT} is busy per lsof" \
     && return
 
-    # Not busy... or no tools to confirm?
-    if (command -v netstat || command -v sockstat || command -v ss || command -v lsof) 2>/dev/null >/dev/null ; then
-        # at least one tool is present, so not busy
-        log_debug "isBusy_NUT_PORT() found that NUT_PORT=${NUT_PORT} is not busy per netstat, sockstat, ss or lsof"
-        return 1
-    fi
-
     # If the current shell interpreter is bash, it can do a bit of networking:
     if [ -n "${BASH_VERSION-}" ]; then
         # NOTE: Probing host names we use in upsd.conf
@@ -143,6 +172,13 @@ isBusy_NUT_PORT() {
         log_warn "isBusy_NUT_PORT() tried with BASH-specific query, and port does not seem busy (or something else errored out)"
     fi
 
+    # Not busy... or no tools to confirm? (or no perms, or no lsof plugin)?
+    if (command -v netstat || command -v sockstat || command -v ss || command -v lsof) 2>/dev/null >/dev/null ; then
+        # at least one tool is present, so not busy
+        log_debug "isBusy_NUT_PORT() found that NUT_PORT=${NUT_PORT} is not busy per netstat, sockstat, ss or lsof"
+        return 1
+    fi
+
     # Assume not busy to not preclude testing in 100% of the cases
     log_warn "isBusy_NUT_PORT() can not say definitively, tools for checking NUT_PORT=$NUT_PORT are not available"
     return 1
@@ -246,26 +282,68 @@ for PROG in upsd upsc dummy-ups upsmon ; do
 done
 
 PID_UPSD=""
+PID_UPSMON=""
 PID_DUMMYUPS=""
 PID_DUMMYUPS1=""
 PID_DUMMYUPS2=""
 
-TESTDIR="$BUILDDIR/tmp"
-# Technically the limit is sizeof(sockaddr.sun_path) for complete socket
-# pathname, which varies 104-108 chars max on systems seen in CI farm;
-# we reserve 17 chars for "/dummy-ups-dummy" longest filename.
-if [ `echo "$TESTDIR" | wc -c` -gt 80 ]; then
-    log_info "'$TESTDIR' is too long to store AF_UNIX socket files, will mktemp"
+# Stash it for some later decisions
+TESTDIR_CALLER="${TESTDIR-}"
+[ -n "${TESTDIR-}" ] || TESTDIR="$BUILDDIR/tmp"
+if [ `echo "${TESTDIR}" | wc -c` -gt 80 ]; then
+    # Technically the limit is sizeof(sockaddr.sun_path) for complete socket
+    # pathname, which varies 104-108 chars max on systems seen in CI farm;
+    # we reserve 17 chars for "/dummy-ups-dummy" longest filename.
+    log_info "'${TESTDIR}' is too long to store AF_UNIX socket files, will mktemp"
+    TESTDIR=""
+else
+    if [ "`id -u`" = 0 ]; then
+        case "${TESTDIR}" in
+            "${HOME}"/*)
+                log_info "Test script was started by 'root' and '${TESTDIR}' seems to be under its home, will mktemp so unprivileged daemons may access their configs, pipes and PID files"
+                TESTDIR=""
+                ;;
+        esac
+    else
+        if ! mkdir -p "${TESTDIR}" || ! [ -w "${TESTDIR}" ] ; then
+            log_info "'${TESTDIR}' could not be created/used, will mktemp"
+            TESTDIR=""
+        fi
+    fi
+fi
+
+if [ x"${TESTDIR}" = x ] ; then
     if ( [ -n "${TMPDIR-}" ] && [ -d "${TMPDIR-}" ] && [ -w "${TMPDIR-}" ] ) ; then
         :
     else
         if [ -d /dev/shm ] && [ -w /dev/shm ]; then TMPDIR=/dev/shm ; else TMPDIR=/tmp ; fi
     fi
+    log_warn "Will now mktemp a TESTDIR under '${TMPDIR}'. It will be wiped when the NIT script exits."
+    log_warn "If you want a pre-determined location, pre-export a usable TESTDIR value."
     TESTDIR="`mktemp -d "${TMPDIR}/nit-tmp.$$.XXXXXX"`" || die "Failed to mktemp"
+    if [ "`id -u`" = 0 ]; then
+        # Cah be protected as 0700 by default
+        chmod ugo+rx "${TESTDIR}"
+    fi
 else
-    rm -rf "${TESTDIR}" || true
+    NUT_CONFPATH="${TESTDIR}/etc"
+    if [ -e "${NUT_CONFPATH}/NIT.env-sandbox-ready" ] ; then
+        log_warn "'${NUT_CONFPATH}/NIT.env-sandbox-ready' exists, do you have another instance of the script still running with same configs?"
+        sleep 3
+    fi
+
+    # NOTE: Keep in sync with NIT_CASE handling and the exit-trap below
+    case "${NIT_CASE}" in
+        generatecfg_*|is*) ;;
+        *)
+            rm -rf "${TESTDIR}" || true
+            ;;
+    esac
 fi
 log_info "Using '$TESTDIR' for generated configs and state files"
+if [ x"${TESTDIR_CALLER}" = x"${TESTDIR}" ] && [ x"${TESTDIR}" != x"$BUILDDIR/tmp" ] ; then
+    log_warn "A caller-provided location is used, it would not be automatically removed after tests nor by 'make clean'"
+fi
 
 mkdir -p "${TESTDIR}/etc" "${TESTDIR}/run" && chmod 750 "${TESTDIR}/run" \
 || die "Failed to create temporary FS structure for the NIT"
@@ -276,24 +354,32 @@ if [ "`id -u`" = 0 ]; then
 fi
 
 stop_daemons() {
-    if [ -n "$PID_UPSD$PID_DUMMYUPS$PID_DUMMYUPS1$PID_DUMMYUPS2" ] ; then
+    if [ -n "$PID_UPSD$PID_UPSMON$PID_DUMMYUPS$PID_DUMMYUPS1$PID_DUMMYUPS2" ] ; then
         log_info "Stopping test daemons"
-        kill -15 $PID_UPSD $PID_DUMMYUPS $PID_DUMMYUPS1 $PID_DUMMYUPS2 2>/dev/null || return 0
-        wait $PID_UPSD $PID_DUMMYUPS $PID_DUMMYUPS1 $PID_DUMMYUPS2 || true
+        kill -15 $PID_UPSD $PID_UPSMON $PID_DUMMYUPS $PID_DUMMYUPS1 $PID_DUMMYUPS2 2>/dev/null || return 0
+        wait $PID_UPSD $PID_UPSMON $PID_DUMMYUPS $PID_DUMMYUPS1 $PID_DUMMYUPS2 || true
     fi
 
     PID_UPSD=""
+    PID_UPSMON=""
     PID_DUMMYUPS=""
     PID_DUMMYUPS1=""
     PID_DUMMYUPS2=""
 }
 
-trap 'RES=$?; stop_daemons; if [ "${TESTDIR}" != "${BUILDDIR}/tmp" ] ; then rm -rf "${TESTDIR}" ; fi; exit $RES;' 0 1 2 3 15
+trap 'RES=$?; case "${NIT_CASE}" in generatecfg_*|is*) ;; *) stop_daemons; if [ x"${TESTDIR}" != x"${BUILDDIR}/tmp" ] && [ x"${TESTDIR}" != x"$TESTDIR_CALLER" ] ; then rm -rf "${TESTDIR}" ; else rm -f "${NUT_CONFPATH}/NIT.env-sandbox-ready" ; fi ;; esac; exit $RES;' 0 1 2 3 15
 
 NUT_STATEPATH="${TESTDIR}/run"
+NUT_PIDPATH="${TESTDIR}/run"
 NUT_ALTPIDPATH="${TESTDIR}/run"
 NUT_CONFPATH="${TESTDIR}/etc"
-export NUT_STATEPATH NUT_ALTPIDPATH NUT_CONFPATH
+export NUT_STATEPATH NUT_PIDPATH NUT_ALTPIDPATH NUT_CONFPATH
+
+if [ -e "${NUT_CONFPATH}/NIT.env-sandbox-ready" ] ; then
+    log_warn "'${NUT_CONFPATH}/NIT.env-sandbox-ready' exists, do you have another instance of the script still running?"
+    sleep 3
+fi
+rm -f "${NUT_CONFPATH}/NIT.env-sandbox-ready" || true
 
 # TODO: Find a portable way to (check and) grab a random unprivileged port?
 if [ -n "${NUT_PORT-}" ] && [ "$NUT_PORT" -gt 0 ] && [ "$NUT_PORT" -lt 65536 ] ; then
@@ -345,6 +431,39 @@ export NUT_PORT
 # Help track collisions in log, if someone else starts a test in same directory
 log_info "Using NUT_PORT=${NUT_PORT} for this test run"
 
+# This file is not used by the test code, it is an
+# aid for "DEBUG_SLEEP=X" mode so the caller can
+# quickly source needed values into their shell.
+#
+# WARNING: Variables in this file are not guaranteed
+# to impact subsequent runs of this script (nit.sh),
+# e.g. NUT_PORT may be inherited, but paths would not be!
+#
+# NOTE: `set` typically wraps the values in quotes,
+# but (maybe?) not all shell implementations do.
+# Just in case, we have a fallback with single quotes.
+# FIXME: We assume no extra quoting or escaping in
+# the values when fallback is used. If this is a
+# problem on any platform (Win/Mac and spaces in
+# paths?) please investigate and fix accordingly.
+set | grep -E '^(NUT_|TESTDIR|LD_LIBRARY_PATH|DEBUG|PATH).*=' \
+| while IFS='=' read K V ; do
+    case "$K" in
+        LD_LIBRARY_PATH_CLIENT|LD_LIBRARY_PATH_ORIG|PATH_*|NUT_PORT_*|TESTDIR_*)
+            continue
+            ;;
+        DEBUG_SLEEP|PATH|LD_LIBRARY_PATH*) printf '### ' ;;
+    esac
+
+    case "$V" in
+        '"'*'"'|"'"*"'")
+            printf "%s=%s\nexport %s\n\n" "$K" "$V" "$K" ;;
+        *)
+            printf "%s='%s'\nexport %s\n\n" "$K" "$V" "$K" ;;
+    esac
+done > "$NUT_CONFPATH/NIT.env"
+log_info "Populated environment variables for this run into $NUT_CONFPATH/NIT.env"
+
 ### upsd.conf: ##################################################
 
 generatecfg_upsd_trivial() {
@@ -362,7 +481,7 @@ EOF
         chmod 640 "$NUT_CONFPATH/upsd.conf"
     fi
 
-    # Some systems listining on symbolic "localhost" actually
+    # Some systems listening on symbolic "localhost" actually
     # only bind to IPv6, and Python telnetlib resolves IPv4
     # and fails its connection tests. Others fare well with
     # both addresses in one command.
@@ -433,10 +552,27 @@ EOF
 
 ### upsmon.conf: ##################################################
 
+updatecfg_upsmon_supplies() {
+    NUMSUP="${1-}"
+    [ -n "$NUMSUP" ] && [ "$NUMSUP" -ge 0 ] || NUMSUP=1
+
+    [ -s "$NUT_CONFPATH/upsmon.conf" ] \
+    || die "Failed to rewrite config - not populated yet: upsmon.conf"
+
+    # NOTE: "sed -i file" is not ubiquitously portable
+    # Using "cat" to retain FS permissions maybe set above
+    sed -e 's,^\(MINSUPPLIES\) [0-9][0-9]*$,\1 '"$NUMSUP"',' \
+        -e 's,^\(MONITOR .*\) [0-9][0-9]* \(.*\)$,\1 '"$NUMSUP"' \2,' \
+        < "$NUT_CONFPATH/upsmon.conf" > "$NUT_CONFPATH/upsmon.conf.tmp" \
+        && ( cat "$NUT_CONFPATH/upsmon.conf.tmp" > "$NUT_CONFPATH/upsmon.conf" ) \
+        && rm -f "$NUT_CONFPATH/upsmon.conf.tmp"
+}
+
 generatecfg_upsmon_trivial() {
     # Populate the configs for the run
+    rm -f "$NUT_STATEPATH/upsmon.sd.log"
     (  echo 'MINSUPPLIES 0' > "$NUT_CONFPATH/upsmon.conf" || exit
-       echo 'SHUTDOWNCMD "echo TESTING_DUMMY_SHUTDOWN_NOW"' >> "$NUT_CONFPATH/upsmon.conf" || exit
+       echo 'SHUTDOWNCMD "echo \"`date`: TESTING_DUMMY_SHUTDOWN_NOW\" | tee \"'"$NUT_STATEPATH"'/upsmon.sd.log\" "' >> "$NUT_CONFPATH/upsmon.conf" || exit
 
        if [ -n "${NUT_DEBUG_MIN-}" ] ; then
            echo "DEBUG_MIN ${NUT_DEBUG_MIN}" >> "$NUT_CONFPATH/upsmon.conf" || exit
@@ -449,30 +585,50 @@ generatecfg_upsmon_trivial() {
     else
         chmod 640 "$NUT_CONFPATH/upsmon.conf"
     fi
+
+    if [ $# -gt 0 ] ; then
+        updatecfg_upsmon_supplies "$1"
+    fi
 }
 
 generatecfg_upsmon_master() {
     generatecfg_upsmon_trivial
-    echo "MONITOR 'dummy@localhost:$NUT_PORT' 0 'dummy-admin-m' '${TESTPASS_UPSMON_PRIMARY}' master" >> "$NUT_CONFPATH/upsmon.conf" \
+    echo "MONITOR \"dummy@localhost:$NUT_PORT\" 0 \"dummy-admin-m\" \"${TESTPASS_UPSMON_PRIMARY}\" master" >> "$NUT_CONFPATH/upsmon.conf" \
     || die "Failed to populate temporary FS structure for the NIT: upsmon.conf"
+
+    if [ $# -gt 0 ] ; then
+        updatecfg_upsmon_supplies "$1"
+    fi
 }
 
 generatecfg_upsmon_primary() {
     generatecfg_upsmon_trivial
-    echo "MONITOR 'dummy@localhost:$NUT_PORT' 0 'dummy-admin' '${TESTPASS_UPSMON_PRIMARY}' primary" >> "$NUT_CONFPATH/upsmon.conf" \
+    echo "MONITOR \"dummy@localhost:$NUT_PORT\" 0 \"dummy-admin\" \"${TESTPASS_UPSMON_PRIMARY}\" primary" >> "$NUT_CONFPATH/upsmon.conf" \
     || die "Failed to populate temporary FS structure for the NIT: upsmon.conf"
+
+    if [ $# -gt 0 ] ; then
+        updatecfg_upsmon_supplies "$1"
+    fi
 }
 
 generatecfg_upsmon_slave() {
     generatecfg_upsmon_trivial
-    echo "MONITOR 'dummy@localhost:$NUT_PORT' 0 'dummy-user-s' '${TESTPASS_UPSMON_SECONDARY}' slave" >> "$NUT_CONFPATH/upsmon.conf" \
+    echo "MONITOR \"dummy@localhost:$NUT_PORT\" 0 \"dummy-user-s\" \"${TESTPASS_UPSMON_SECONDARY}\" slave" >> "$NUT_CONFPATH/upsmon.conf" \
     || die "Failed to populate temporary FS structure for the NIT: upsmon.conf"
+
+    if [ $# -gt 0 ] ; then
+        updatecfg_upsmon_supplies "$1"
+    fi
 }
 
 generatecfg_upsmon_secondary() {
     generatecfg_upsmon_trivial
-    echo "MONITOR 'dummy@localhost:$NUT_PORT' 0 'dummy-user' '${TESTPASS_UPSMON_SECONDARY}' secondary" >> "$NUT_CONFPATH/upsmon.conf" \
+    echo "MONITOR \"dummy@localhost:$NUT_PORT\" 0 \"dummy-user\" \"${TESTPASS_UPSMON_SECONDARY}\" secondary" >> "$NUT_CONFPATH/upsmon.conf" \
     || die "Failed to populate temporary FS structure for the NIT: upsmon.conf"
+
+    if [ $# -gt 0 ] ; then
+        updatecfg_upsmon_supplies "$1"
+    fi
 }
 
 ### ups.conf: ##################################################
@@ -561,7 +717,7 @@ PASSED=0
 testcase_upsd_no_configs_at_all() {
     log_separator
     log_info "[testcase_upsd_no_configs_at_all] Test UPSD without configs at all"
-    upsd -F
+    upsd ${ARG_FG}
     if [ "$?" = 0 ]; then
         log_error "[testcase_upsd_no_configs_at_all] upsd should fail without configs"
         FAILED="`expr $FAILED + 1`"
@@ -576,7 +732,7 @@ testcase_upsd_no_configs_driver_file() {
     log_separator
     log_info "[testcase_upsd_no_configs_driver_file] Test UPSD without driver config file"
     generatecfg_upsd_trivial
-    upsd -F
+    upsd ${ARG_FG}
     if [ "$?" = 0 ]; then
         log_error "[testcase_upsd_no_configs_driver_file] upsd should fail without driver config file"
         FAILED="`expr $FAILED + 1`"
@@ -592,7 +748,7 @@ testcase_upsd_no_configs_in_driver_file() {
     log_info "[testcase_upsd_no_configs_in_driver_file] Test UPSD without drivers defined in config file"
     generatecfg_upsd_trivial
     generatecfg_ups_trivial
-    upsd -F
+    upsd ${ARG_FG}
     if [ "$?" = 0 ]; then
         log_error "[testcase_upsd_no_configs_in_driver_file] upsd should fail without drivers defined in config file"
         FAILED="`expr $FAILED + 1`"
@@ -610,7 +766,7 @@ upsd_start_loop() {
         return 0
     fi
 
-    upsd -F &
+    upsd ${ARG_FG} &
     PID_UPSD="$!"
     log_debug "[${TESTCASE}] Tried to start UPSD as PID $PID_UPSD"
     sleep 2
@@ -640,7 +796,7 @@ upsd_start_loop() {
         log_warn "[${TESTCASE}] Port ${NUT_PORT} is ${PORT_WORD}listening and UPSD PID $PID_UPSD is not alive, will sleep and retry"
 
         sleep 10
-        upsd -F &
+        upsd ${ARG_FG} &
         PID_UPSD="$!"
         log_warn "[${TESTCASE}] Tried to start UPSD again, now as PID $PID_UPSD"
         sleep 5
@@ -787,17 +943,17 @@ sandbox_start_drivers() {
     sandbox_generate_configs
 
     log_info "Starting dummy-ups driver(s) for sandbox"
-    #upsdrvctl -F start dummy &
-    dummy-ups -a dummy -F &
+    #upsdrvctl ${ARG_FG} start dummy &
+    dummy-ups -a dummy ${ARG_FG} &
     PID_DUMMYUPS="$!"
     log_debug "Tried to start dummy-ups driver for 'dummy' as PID $PID_DUMMYUPS"
 
     if [ x"${TOP_SRCDIR}" != x ]; then
-        dummy-ups -a UPS1 -F &
+        dummy-ups -a UPS1 ${ARG_FG} &
         PID_DUMMYUPS1="$!"
         log_debug "Tried to start dummy-ups driver for 'UPS1' as PID $PID_DUMMYUPS1"
 
-        dummy-ups -a UPS2 -F &
+        dummy-ups -a UPS2 ${ARG_FG} &
         PID_DUMMYUPS2="$!"
         log_debug "Tried to start dummy-ups driver for 'UPS2' as PID $PID_DUMMYUPS2"
     fi
@@ -885,7 +1041,7 @@ testcase_sandbox_start_upsd_after_drivers() {
 
     # Not calling upsd_start_loop() here, before drivers
     # If the server starts, fine; if not - we retry below
-    upsd -F &
+    upsd ${ARG_FG} &
     PID_UPSD="$!"
     log_debug "[testcase_sandbox_start_upsd_after_drivers] Tried to start UPSD as PID $PID_UPSD"
 
@@ -1045,6 +1201,7 @@ isTestablePython() {
     if [ x"${PY_SHEBANG}" = x"#!no" ] ; then
         return 1
     fi
+    log_debug "=======\nDetected python shebang: '${PY_SHEBANG}'"
     return 0
 }
 
@@ -1332,6 +1489,45 @@ testcases_sandbox_nutscanner() {
 
 # TODO: Some upsmon tests?
 
+upsmon_start_loop() {
+    TESTCASE="${1-upsmon_start_loop}"
+
+    if isPidAlive "$PID_UPSMON" ; then
+        return 0
+    fi
+
+    upsmon ${ARG_FG} &
+    PID_UPSMON="$!"
+    log_debug "[${TESTCASE}] Tried to start UPSMON as PID $PID_UPSMON"
+    sleep 2
+    # Due to severe config errors, client could have died by now
+    # TOTHINK: Loop like for upsd?
+
+    # Return code is 0/OK if the client is alive
+    if isPidAlive "$PID_UPSMON" ; then
+        log_debug "[${TESTCASE}] UPSMON PID $PID_UPSMON is alive after a short while"
+        return
+    fi
+
+    log_error "[${TESTCASE}] UPSMON PID $PID_UPSMON is not alive after a short while"
+    return 1
+}
+
+sandbox_start_upsmon_master() {
+    # Optional arg can specify amount of power sources to MONITOR and require
+    if isPidAlive "$PID_UPSMON" ; then
+        # FIXME: Kill and restart? Reconfigure and reload?
+        return 0
+    fi
+
+    sandbox_generate_configs
+    generatecfg_upsmon_master "$@"
+
+    log_info "Starting UPSMON as master for sandbox"
+
+    upsmon_start_loop "sandbox"
+}
+
 ####################################
 
 testgroup_sandbox() {
@@ -1383,6 +1579,16 @@ testgroup_sandbox_nutscanner() {
     sandbox_forget_configs
 }
 
+testgroup_sandbox_upsmon_master() {
+    # Arrange for quick test iterations
+    # Optional arg can specify amount of power sources to MONITOR and require
+    testcase_sandbox_start_drivers_after_upsd
+    sandbox_start_upsmon_master "$@"
+
+    log_separator
+    sandbox_forget_configs
+}
+
 ################################################################
 
 case "${NIT_CASE}" in
@@ -1396,7 +1602,28 @@ case "${NIT_CASE}" in
         log_warn "Be sure to have previously run with DEBUG_SLEEP and"
         log_warn "   have exported the NUT_PORT upsd is listening on!"
         log_warn "========================================================"
-        "${NIT_CASE}" ;;
+        # NOTE: Not quoted, can have further arguments
+        # e.g. NIT_CASE="testgroup_sandbox_upsmon_master 1"
+        eval ${NIT_CASE}
+        ;;
+    generatecfg_*|is*)
+        # NOTE: Keep in sync with TESTDIR cleanup above
+        # (at start-up and at the exit-trap) and stop_daemons below
+        log_warn "========================================================"
+        log_warn "You asked to run just a specific helper method: '${NIT_CASE}'"
+        log_warn "Populated environment variables for this run into a file so you can source them: . '$NUT_CONFPATH/NIT.env'"
+        log_warn "Notably, NUT_CONFPATH='$NUT_CONFPATH' now"
+        log_warn "========================================================"
+        # NOTE: Not quoted, can have further arguments
+        eval ${NIT_CASE}
+        if [ $? = 0 ] ; then
+            PASSED="`expr $PASSED + 1`"
+        else
+            FAILED="`expr $FAILED + 1`"
+            FAILED_FUNCS="$FAILED_FUNCS $NIT_CASE"
+        fi
+        unset DEBUG_SLEEP
+        ;;
     "") # Default test groups:
         testgroup_upsd_invalid_configs
         testgroup_upsd_questionable_configs
@@ -1419,15 +1646,41 @@ if [ -n "${DEBUG_SLEEP-}" ] ; then
     fi
 
     log_separator
-    log_info "Sleeping now as asked (for ${DEBUG_SLEEP} seconds starting `date -u`), so you can play with the driver and server running; hint: export NUT_PORT=$NUT_PORT"
+    log_info "Sleeping now as asked (for ${DEBUG_SLEEP} seconds starting `date -u`), so you can play with the driver and server running"
+    log_info "Populated environment variables for this run into a file so you can source them: . '$NUT_CONFPATH/NIT.env'"
+    printf "PID_NIT_SCRIPT='%s'\nexport PID_NIT_SCRIPT\n" "$$" >> "$NUT_CONFPATH/NIT.env"
+    set | grep -E '^TESTPASS_|PID_[^ =]*='"'?[0-9][0-9]*'?$" | while IFS='=' read K V ; do
+        V="`echo "$V" | tr -d "'"`"
+        # Dummy comment to reset syntax highlighting due to ' quote above
+        if [ -n "$V" ] ; then
+            printf "%s='%s'\nexport %s\n" "$K" "$V" "$K"
+        fi
+    done >> "$NUT_CONFPATH/NIT.env"
+    log_separator
+    cat "$NUT_CONFPATH/NIT.env"
     log_separator
+    log_info "See above about important variables from the test sandbox and a way to 'source' them into your shell, e.g.: . '$NUT_CONFPATH/NIT.env'"
+
+    if [ x"${TESTDIR_CALLER}" != x"${TESTDIR}" ] && [ x"${TESTDIR}" != x"$BUILDDIR/tmp" ] ; then
+        log_warn "A temporary random TESTDIR location is used, it would be automatically removed after this script exits!"
+    fi
+
+    log_info "You may want to press Ctrl+Z now and command 'bg' to the shell, if you did not start '$0 &' backgrounded already"
+    log_info "To kill the script early, return it to foreground with 'fg' and press Ctrl+C, or 'kill -2 \$PID_NIT_SCRIPT' (kill -2 $$)"
+
+    log_info "Remember that in shell/scripting you can probe for '${NUT_CONFPATH}/NIT.env-sandbox-ready' which only appears at this moment"
+    touch "${NUT_CONFPATH}/NIT.env-sandbox-ready"
 
     sleep "${DEBUG_SLEEP}"
     log_info "Sleep finished"
     log_separator
 fi
 
-stop_daemons
+# We have a trap.... but for good measure, do some explicit clean-up:
+case "${NIT_CASE}" in
+    generatecfg_*|is*) ;;
+    *) stop_daemons ;;
+esac
 
 if [ "$PASSED" = 0 ] || [ "$FAILED" != 0 ] ; then
     die "Some test scenarios failed!"
diff --git a/tests/cpputest-client.cpp b/tests/cpputest-client.cpp
index 1c21cd589d..bcd6ae719c 100644
--- a/tests/cpputest-client.cpp
+++ b/tests/cpputest-client.cpp
@@ -6,7 +6,8 @@
    as opposed to nutclienttest.cpp which unit-tests the class API etc.
    in isolated-binary fashion.
 
-   Copyright (C) 2022  Jim Klimov <jimklimov@gmail.com>
+   Copyright (C)
+	2022-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -25,8 +26,13 @@
 
 #include "common.h"
 
-/* Current CPPUnit offends the honor of C++98 */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
+#include <stdexcept>
+#include <cstdint>
+#include <cstdlib>
+#include <stdlib.h>
+
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
 #pragma GCC diagnostic push
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
 #  pragma GCC diagnostic ignored "-Wglobal-constructors"
@@ -34,13 +40,33 @@
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
 #  pragma GCC diagnostic ignored "-Wexit-time-destructors"
 # endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
 #endif
 
 #include <cppunit/extensions/HelperMacros.h>
-#include <stdexcept>
-#include <cstdint>
-#include <cstdlib>
-#include <stdlib.h>
 
 namespace nut {
 
@@ -474,6 +500,9 @@ void NutActiveClientTest::test_auth_primary() {
 
 } // namespace nut {}
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
-#pragma GCC diagnostic pop
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
 #endif
diff --git a/tests/cpputest.cpp b/tests/cpputest.cpp
index 099e00ebd8..be2414d977 100644
--- a/tests/cpputest.cpp
+++ b/tests/cpputest.cpp
@@ -2,7 +2,7 @@
 
    Copyright (C)
 	2012	Emilien Kia <emilienkia-guest@alioth.debian.org>
-	2020	Jim Klimov <jimklimov@gmail.com>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -23,6 +23,46 @@
 
 #include <stdexcept>
 #include <cstdlib>
+
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ZERO_AS_NULL_POINTER_CONSTANT_BESIDEFUNC)
+#pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
+#  pragma GCC diagnostic ignored "-Wglobal-constructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
+#  pragma GCC diagnostic ignored "-Wexit-time-destructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ZERO_AS_NULL_POINTER_CONSTANT_BESIDEFUNC
+/* Note: this silencer is only needed here due to test bodies */
+#  pragma GCC diagnostic ignored "-Wzero-as-null-pointer-constant"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
+#endif
+
 #include <cppunit/TestResult.h>
 #include <cppunit/CompilerOutputter.h>
 #include <cppunit/TextTestProgressListener.h>
@@ -104,3 +144,10 @@ int main(int argc, char* argv[])
     "'" << ( wasSucessful ? "true" : "false" ) << "'" << std::endl;
   return wasSucessful ? 0 : 1;
 }
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ZERO_AS_NULL_POINTER_CONSTANT_BESIDEFUNC)
+# pragma GCC diagnostic pop
+#endif
diff --git a/tests/driver-stub-usb.c b/tests/driver-stub-usb.c
new file mode 100644
index 0000000000..6cb557a75c
--- /dev/null
+++ b/tests/driver-stub-usb.c
@@ -0,0 +1,67 @@
+/* placeholder/mock method implementations to just directly use driver
+ * source code as done for belkin-hid.c (and eventually similar code)
+ * for almost-in-vivo testing (and minimal intrusion to that codebase).
+ * See also: getexponenttest-belkin-hid.c
+ *
+ * Copyright (C)
+ *      2024   Jim Klimov <jimklimov+nut@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "common.h"
+
+#include "usb-common.h"
+int is_usb_device_supported(usb_device_id_t *usb_device_id_list, USBDevice_t *device) {
+	NUT_UNUSED_VARIABLE(usb_device_id_list);
+	NUT_UNUSED_VARIABLE(device);
+	return -1;
+}
+
+#include "usbhid-ups.h"
+hid_dev_handle_t udev = HID_DEV_HANDLE_CLOSED;
+info_lkp_t beeper_info[] = { { 0, NULL, NULL, NULL } };
+info_lkp_t date_conversion[] = { { 0, NULL, NULL, NULL } };
+info_lkp_t stringid_conversion[] = { { 0, NULL, NULL, NULL } };
+info_lkp_t divide_by_10_conversion[] = { { 0, NULL, NULL, NULL } };
+info_lkp_t divide_by_100_conversion[] = { { 0, NULL, NULL, NULL } };
+
+void possibly_supported(const char *mfr, HIDDevice_t *hd) {
+	NUT_UNUSED_VARIABLE(mfr);
+	NUT_UNUSED_VARIABLE(hd);
+}
+
+int fix_report_desc(HIDDevice_t *arg_pDev, HIDDesc_t *arg_pDesc) {
+	NUT_UNUSED_VARIABLE(arg_pDev);
+	NUT_UNUSED_VARIABLE(arg_pDesc);
+	return -1;
+}
+
+#include "libhid.h"
+usage_lkp_t hid_usage_lkp[] = { {NULL, 0} };
+char *HIDGetItemString(hid_dev_handle_t arg_udev, const char *hidpath, char *buf, size_t buflen, usage_tables_t *utab) {
+	NUT_UNUSED_VARIABLE(arg_udev);
+	NUT_UNUSED_VARIABLE(hidpath);
+	NUT_UNUSED_VARIABLE(buf);
+	NUT_UNUSED_VARIABLE(buflen);
+	NUT_UNUSED_VARIABLE(utab);
+	return NULL;
+}
+
+#include "main.h"
+char *getval(const char *var) {
+	NUT_UNUSED_VARIABLE(var);
+	return NULL;
+}
diff --git a/tests/example.cpp b/tests/example.cpp
index cb52e9365c..90b03269f3 100644
--- a/tests/example.cpp
+++ b/tests/example.cpp
@@ -2,7 +2,7 @@
 
    Copyright (C)
 	2012	Emilien Kia <emilienkia-guest@alioth.debian.org>
-	2020	Jim Klimov <jimklimov@gmail.com>
+	2020-2024	Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -21,8 +21,8 @@
 
 #include "common.h"
 
-/* Current CPPUnit offends the honor of C++98 */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
 #pragma GCC diagnostic push
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
 #  pragma GCC diagnostic ignored "-Wglobal-constructors"
@@ -30,6 +30,30 @@
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
 #  pragma GCC diagnostic ignored "-Wexit-time-destructors"
 # endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
 #endif
 
 #include <cppunit/extensions/HelperMacros.h>
@@ -74,6 +98,9 @@ void ExampleTest::testOne()
   CPPUNIT_ASSERT_EQUAL( i, cast );
 }
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
-#pragma GCC diagnostic pop
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
 #endif
diff --git a/tests/getexponenttest-belkin-hid.c b/tests/getexponenttest-belkin-hid.c
new file mode 100644
index 0000000000..5cb872b02b
--- /dev/null
+++ b/tests/getexponenttest-belkin-hid.c
@@ -0,0 +1,204 @@
+/* getexponenttest-belkin-hid - check detection of correct multiplication
+ * exponent value for miniscule readings from USB HID (as used in the
+ * drivers/belkin-hid.c subdriver of usbhid-ups).
+ * Eventually may be extended to similar tests for other drivers' methods,
+ * or more likely cloned to #include them in similar fashion.
+ *
+ * See also:
+ *  https://github.com/networkupstools/nut/issues/2370
+ *
+ * Copyright (C)
+ *      2024   Jim Klimov <jimklimov+nut@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "config.h"
+
+#include "nut_stdint.h"
+#include "nut_float.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "common.h"
+
+#include "belkin-hid.c"
+/* from drivers/belkin-hid.c we test:
+extern double liebert_config_voltage_mult, liebert_line_voltage_mult;
+const char *liebert_config_voltage_fun(double value);
+const char *liebert_line_voltage_fun(double value);
+ */
+
+static void Usage(char *name) {
+/*
+	printf("%s {-c <config_voltage> | -l <line_voltage>} <expected_multiplier> <expected_voltage>\n", name);
+	printf("\n");
+	printf("%s -c 12\n", name);
+	printf("%s -l 0.001212\n", name);
+	printf("%s -l 1.39e-06\n", name);
+*/
+	printf("%s\nIf no arguments are given a builtin set of tests are run.\n", name);
+}
+
+static int RunBuiltInTests(char *argv[]) {
+	int exitStatus = 0;
+	size_t i;
+
+	double	rawValue, value, mult;
+	const char	*valueStr;
+
+	static char* methodName[2] = {
+		"liebert_config_voltage_mult()   ",
+		"liebert_line_voltage_mult()     "
+	};
+
+	static struct {
+		char *buf;			/* raw voltage as a string (from CLI input, e.g. NUT driver log trace) */
+		double expectedRawValue;	/* parsed raw voltage (as seen in USB HID reports) */
+		char type;			/* 1 = config, 2 = line */
+		double expectedMult;		/* expected liebert_config_voltage_mult or liebert_line_voltage_mult */
+		double expectedValue;		/* the expected result of decoding the value in the buffer */
+	} testData[] = {
+		{.buf = "0.000273",	.expectedRawValue = 0.000273,	.type = 2, .expectedMult = 1e5, .expectedValue = 27.3	},
+		{.buf = "0.001212",	.expectedRawValue = 0.001212,	.type = 2, .expectedMult = 1e5, .expectedValue = 121.2	},
+		{.buf = "0.002456",	.expectedRawValue = 0.002456,	.type = 2, .expectedMult = 1e5, .expectedValue = 245.6	},
+		{.buf = "0.003801",	.expectedRawValue = 0.003801,	.type = 2, .expectedMult = 1e5, .expectedValue = 380.1	},
+		{.buf = "0.004151",	.expectedRawValue = 0.004151,	.type = 2, .expectedMult = 1e5, .expectedValue = 415.1	},
+
+		{.buf = "1.39e-06",	.expectedRawValue = 0.00000139,	.type = 2, .expectedMult = 1e7, .expectedValue = 13.9	},
+		{.buf = "1.273e-05",	.expectedRawValue = 0.00001273,	.type = 2, .expectedMult = 1e7, .expectedValue = 127.3	},
+		{.buf = "2.201e-05",	.expectedRawValue = 0.00002201,	.type = 2, .expectedMult = 1e7, .expectedValue = 220.1	},
+		{.buf = "4.201e-05",	.expectedRawValue = 0.00004201,	.type = 2, .expectedMult = 1e7, .expectedValue = 420.1	},
+
+		/* Edge cases - what should not be converted (good enough already) */
+		{.buf = "12",	.expectedRawValue = 12.0,	.type = 2, .expectedMult = 1, .expectedValue = 12.0	},
+		{.buf = "12.3",	.expectedRawValue = 12.3,	.type = 2, .expectedMult = 1, .expectedValue = 12.3	},
+		{.buf = "232.1",	.expectedRawValue = 232.1,	.type = 2, .expectedMult = 1, .expectedValue = 232.1	},
+		{.buf = "240",	.expectedRawValue = 240.0,	.type = 2, .expectedMult = 1, .expectedValue = 240.0	},
+
+		/* Config values (nominal battery/input/... voltage) are often integers: */
+		{.buf = "24",	.expectedRawValue = 24.0,	.type = 1, .expectedMult = 1, .expectedValue = 24.0	},
+		{.buf = "120",	.expectedRawValue = 120.0,	.type = 1, .expectedMult = 1, .expectedValue = 120.0	}
+	};
+
+	NUT_UNUSED_VARIABLE(argv);
+
+	for (i = 0; i < SIZEOF_ARRAY(testData); i++) {
+		liebert_line_voltage_mult = 1.0;
+		liebert_config_voltage_mult = 1.0;
+
+		rawValue = strtod(testData[i].buf, NULL);
+		if (!d_equal(rawValue, testData[i].expectedRawValue)) {
+			printf(" value '%s' parsing FAIL: got %g expected %g\n",
+				testData[i].buf, rawValue, testData[i].expectedRawValue);
+			/* Fix testData definition! */
+			exitStatus = 1;
+		}
+
+		switch (testData[i].type) {
+			case 1:
+				valueStr = liebert_config_voltage_fun(rawValue);
+				mult = liebert_config_voltage_mult;
+				/* NOTE: The method does also set a default
+				 * liebert_line_voltage_mult if config voltage
+				 * is miniscule and not a plain integer */
+				break;
+
+			case 2:
+				valueStr = liebert_line_voltage_fun(rawValue);
+				mult = liebert_line_voltage_mult;
+				break;
+
+			default:
+				printf(" invalid entry\n");
+				continue;
+		}
+
+		printf("Test #%" PRIiSIZE "  \t", i + 1);
+		value = strtod(valueStr, NULL);
+		if (d_equal(value, testData[i].expectedValue) && d_equal(mult, testData[i].expectedMult)) {
+			printf("%s\tGOT value %9g\tmult %6g PASS\n",
+				(testData[i].type < 1 || testData[i].type > 3 ? "<null>" : methodName[testData[i].type - 1]),
+				value, mult);
+		} else {
+			printf("%s\tGOT value %9g\tmult %6g FAIL"
+				"\tEXPECTED v=%7g\tm=%7g"
+				"\tORIGINAL (string)'%s'\t=> (double)%g\n",
+				(testData[i].type < 1 || testData[i].type > 2 ? "<null>" : methodName[testData[i].type - 1]),
+				value, mult,
+				testData[i].expectedValue,
+				testData[i].expectedMult,
+				testData[i].buf, rawValue);
+			exitStatus = 1;
+		}
+	}
+
+	return (exitStatus);
+}
+
+/*
+static int RunCommandLineTest(char *argv[]) {
+	uint8_t reportBuf[64];
+	size_t bufSize;
+	char *start, *end;
+	HIDData_t data;
+	long value, expectedValue;
+
+	start = argv[1];
+	end = NULL;
+	for (bufSize = 0; *start != 0; bufSize++) {
+		reportBuf[bufSize] = (uint8_t) strtol(start, (char **)&end, 16);
+		if (start == end) break;
+		start = end;
+	}
+	memset((void *)&data, 0, sizeof(data));
+	data.Offset = (uint8_t) atoi(argv[2]);
+	data.Size = (uint8_t) atoi(argv[3]);
+	data.LogMin = strtol(argv[4], 0, 0);
+	data.LogMax = strtol(argv[5], 0, 0);
+	expectedValue = strtol(argv[6], 0, 0);
+
+	GetValue(reportBuf, &data, &value);
+
+	printf("Test #0 ");
+	PrintBufAndData(reportBuf, bufSize, &data);
+	if (value == expectedValue) {
+		printf(" value %ld PASS\n", value);
+		return (0);
+	} else {
+		printf(" value %ld FAIL expected %ld\n", value, expectedValue);
+		return (1);
+	}
+}
+*/
+
+int main (int argc, char *argv[]) {
+	int status;
+
+	switch (argc) {
+	case 1:
+		status = RunBuiltInTests(argv);
+		break;
+/*
+	case 7:
+		status = RunCommandLineTest(argv);
+		break;
+*/
+	default:
+		Usage(argv[0]);
+		status = 2;
+	}
+	return(status);
+}
diff --git a/tests/nutbooltest.c b/tests/nutbooltest.c
new file mode 100644
index 0000000000..41f679643f
--- /dev/null
+++ b/tests/nutbooltest.c
@@ -0,0 +1,57 @@
+/*  nutbooltest.c - test custom nut_bool_t usability
+ *
+ *  Copyright (C)
+ *      2024            Jim Klimov <jimklimov+nut@gmail.com>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#include "config.h"
+#include "nut_bool.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(void)
+{
+	nut_bool_t bt = true, bf = false;
+	int ret = 0;
+
+	/* Check basic boolean operations */
+	if (bf)		ret++;
+	if (!bt)	ret++;
+	if (!bt == !bf)	ret++;
+	if (bt == bf)	ret++;
+
+	if (!(!bt == bf))	ret++;
+	if (!(bt == !bf))	ret++;
+
+	if (!(bt != bf))	ret++;
+	if (!(!bt != !bf))	ret++;
+
+	if (bf && bt)		ret++;
+	if (!bf && !bt)		ret++;
+
+	if (!(!bf && bt))	ret++;
+	if (!(bf || bt))	ret++;
+	if (!(!bf || !bt))	ret++;
+
+	if (ret != 0)
+		printf("nutbooltest collected %i errors", ret);
+
+	return (ret != 0);
+}
diff --git a/tests/nutclienttest.cpp b/tests/nutclienttest.cpp
index 774e8c6b8a..15879930b5 100644
--- a/tests/nutclienttest.cpp
+++ b/tests/nutclienttest.cpp
@@ -1,7 +1,8 @@
 /* nutclienttest - CppUnit nutclient unit test
 
-   Copyright (C) 2016  Emilien Kia <emilien.kia@gmail.com>
-   Copyright (C) 2020 - 2021  Jim Klimov <jimklimov@gmail.com>
+   Copyright (C)
+	2016  Emilien Kia <emilien.kia@gmail.com>
+	2020 - 2024  Jim Klimov <jimklimov+nut@gmail.com>
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -20,8 +21,8 @@
 
 #include "common.h"
 
-/* Current CPPUnit offends the honor of C++98 */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
 #pragma GCC diagnostic push
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
 #  pragma GCC diagnostic ignored "-Wglobal-constructors"
@@ -29,6 +30,30 @@
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
 #  pragma GCC diagnostic ignored "-Wexit-time-destructors"
 # endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
 #endif
 
 #include <cppunit/extensions/HelperMacros.h>
@@ -520,6 +545,9 @@ void NutClientTest::test_nutclientstub_dev() {
 
 } // namespace nut {}
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS)
-#pragma GCC diagnostic pop
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
 #endif
diff --git a/tests/nutconf_parser_ut.cpp b/tests/nutconf_parser_ut.cpp
index f429b28cc9..d5e0652273 100644
--- a/tests/nutconf_parser_ut.cpp
+++ b/tests/nutconf_parser_ut.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
 	2012	Emilien Kia <emilienkia-guest@alioth.debian.org>
+	2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -21,8 +22,6 @@
 
 #include "config.h"
 
-#include <cppunit/extensions/HelperMacros.h>
-
 // Define to de-activate protection of parsing tool members:
 #define UNITEST_MODE 1
 
@@ -33,34 +32,79 @@ using namespace nut;
 #include <algorithm>
 using namespace std;
 
+extern "C" {
+	extern bool verbose;
+}
+
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+#pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
+#  pragma GCC diagnostic ignored "-Wglobal-constructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
+#  pragma GCC diagnostic ignored "-Wexit-time-destructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
+#endif
+
+#include <cppunit/extensions/HelperMacros.h>
+
 class NutConfTest : public CppUnit::TestFixture
 {
-  CPPUNIT_TEST_SUITE( NutConfTest );
-    CPPUNIT_TEST( testOptions );
-    CPPUNIT_TEST( testParseCHARS );
-    CPPUNIT_TEST( testParseSTRCHARS );
-    CPPUNIT_TEST( testPasreToken );
-    CPPUNIT_TEST( testPasreTokenWithoutColon );
-	CPPUNIT_TEST( testGenericConfigParser );
-	CPPUNIT_TEST( testUpsmonConfigParser );
-	CPPUNIT_TEST( testNutConfConfigParser );
-	CPPUNIT_TEST( testUpsdConfigParser );
-  CPPUNIT_TEST_SUITE_END();
+	CPPUNIT_TEST_SUITE( NutConfTest );
+		CPPUNIT_TEST( testOptions );
+		CPPUNIT_TEST( testParseCHARS );
+		CPPUNIT_TEST( testParseSTRCHARS );
+		CPPUNIT_TEST( testParseBoolInt );
+		CPPUNIT_TEST( testParseBoolIntStrict );
+		CPPUNIT_TEST( testParseToken );
+		CPPUNIT_TEST( testParseTokenWithoutColon );
+		CPPUNIT_TEST( testGenericConfigParser );
+		CPPUNIT_TEST( testUpsmonConfigParser );
+		CPPUNIT_TEST( testNutConfConfigParser );
+		CPPUNIT_TEST( testUpsdConfigParser );
+	CPPUNIT_TEST_SUITE_END();
 
 public:
-  void setUp() override;
-  void tearDown() override;
-
-  void testOptions();
-  void testParseCHARS();
-  void testParseSTRCHARS();
-  void testPasreToken();
-  void testPasreTokenWithoutColon();
-
-  void testGenericConfigParser();
-  void testUpsmonConfigParser();
-  void testNutConfConfigParser();
-  void testUpsdConfigParser();
+	void setUp() override;
+	void tearDown() override;
+
+	void testOptions();
+	void testParseCHARS();
+	void testParseSTRCHARS();
+	void testParseBoolInt();
+	void testParseBoolIntStrict();
+	void testParseToken();
+	void testParseTokenWithoutColon();
+
+	void testGenericConfigParser();
+	void testUpsmonConfigParser();
+	void testNutConfConfigParser();
+	void testUpsdConfigParser();
 };
 
 // Registers the fixture into the 'registry'
@@ -139,7 +183,340 @@ void NutConfTest::testParseSTRCHARS()
     }
 }
 
-void NutConfTest::testPasreToken()
+void NutConfTest::testParseBoolInt()
+{
+	// NOTE: Can not use CPPUNIT_ASSERT_EQUAL() below, requires an assertEqual() method
+	BoolInt bi;
+	bi.bool01 = true;
+
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be not 'set()' initially", !(bi.set()));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to an int",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to an int",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "2"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "on"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "no"));
+/*
+	// Actually not "must throw", just returns false for any comparisons - see above
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (string)",
+		if (bi == "1")  {}, std::invalid_argument);
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (int)",
+		if (bi == 1)    {}, std::invalid_argument);
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (bool)",
+		if (bi == true) {}, std::invalid_argument);
+*/
+
+	bi = 42;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from int", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == 42));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of int", (bi == "42"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+
+	bi = true;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from bool", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == true));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int value of bool", (bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	bi = false;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from bool", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == false));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int value of bool", (bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	bi = "1";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == 1));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int as string", (bi == "1"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool as string", (bi == "true"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool as string",
+		CPPUNIT_ASSERT(bi == "false"));
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt comparison to invalid strings must throw exceptions",
+		if (bi == "1.8") {}, std::invalid_argument);
+
+	bi = "-1";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from string", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == -1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+
+	bi = "off";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from string", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == false));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int value of bool", (bi == 0));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "off"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "false"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "0"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "no"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "yes"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "true"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "1"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "on"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "ok"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "AbraCadabra"), std::invalid_argument);
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "1.5"), std::invalid_argument);
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "-3.8"), std::invalid_argument);
+
+	// Standard casing only
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "OFF"), std::invalid_argument);
+
+	// Not-strict comparisons: int or string 0/1 values are bools
+	std::string s;
+	bi << "true";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value", (s == "yes"));
+
+	bi << false;
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value", (s == "no"));
+
+	bi << 1;
+	s = bi.toString();
+	if (verbose)
+		std::cerr << "Non-strict? " << bi.bool01 << " : numeric 1 "
+				<< "=> (string)'" << s << "' aka (ostream)'" << bi << "'"
+				<< std::endl;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => bool)", (s == "yes"));
+
+	bi = 0;
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => bool)", (s == "no"));
+
+	bi = "1";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => bool)", (s == "yes"));
+
+	bi = "0";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => bool)", (s == "no"));
+
+	bi.clear();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be not 'set()' after 'clear()", !(bi.set()));
+}
+
+void NutConfTest::testParseBoolIntStrict()
+{
+	// NOTE: Can not use CPPUNIT_ASSERT_EQUAL() below, requires an assertEqual() method
+	BoolInt bi;
+	bi.bool01 = false;
+
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be not 'set()' initially", !(bi.set()));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to an int",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to an int",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "2"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "on"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("Unassigned BoolInt should not be equal to a string",
+		CPPUNIT_ASSERT(bi == "no"));
+/*
+	// Actually not "must throw", just returns false for any comparisons - see above
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (string)",
+		if (bi == "1")  {}, std::invalid_argument);
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (int)",
+		if (bi == 1)    {}, std::invalid_argument);
+	CPPUNIT_ASSERT_THROW_MESSAGE("Unassigned BoolInt comparisons must throw exceptions (bool)",
+		if (bi == true) {}, std::invalid_argument);
+*/
+
+	bi = 42;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from int", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == 42));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of int", (bi == "42"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+
+	bi = true;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from bool", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the int value of bool",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	bi = false;
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from bool", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to int value of bool",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	bi = "1";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == 1));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int as string", (bi == "1"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the bool as string",
+		CPPUNIT_ASSERT(bi == "true"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the bool as string",
+		CPPUNIT_ASSERT(bi == "true"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool as string",
+		CPPUNIT_ASSERT(bi == "false"));
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt comparison to invalid strings must throw exceptions",
+		if (bi == "1.8") {}, std::invalid_argument);
+
+	bi = "-1";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from string", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the int", (bi == -1));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of int", (bi == "-1"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to a bool",
+		CPPUNIT_ASSERT(bi == false));
+
+	bi = "off";
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be 'set()' after assignment from string", bi.set());
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the bool", (bi == false));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the int value of bool",
+		CPPUNIT_ASSERT(bi == 0));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "off"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "false"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt (strict) should not be equal to the string value of bool (seemingly int)",
+		CPPUNIT_ASSERT(bi == "0"));
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be equal to the string value of bool", (bi == "no"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "yes"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "true"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "1"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "on"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to the string value of another bool",
+		CPPUNIT_ASSERT(bi == "ok"));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another bool",
+		CPPUNIT_ASSERT(bi == true));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to int value of another bool",
+		CPPUNIT_ASSERT(bi == 1));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to another int",
+		CPPUNIT_ASSERT(bi == 2));
+	CPPUNIT_ASSERT_ASSERTION_FAIL_MESSAGE("BoolInt should not be equal to old int",
+		CPPUNIT_ASSERT(bi == 42));
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "AbraCadabra"), std::invalid_argument);
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "1.5"), std::invalid_argument);
+
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "-3.8"), std::invalid_argument);
+
+	// Standard casing only
+	CPPUNIT_ASSERT_THROW_MESSAGE("BoolInt assignment from invalid strings must throw exceptions",
+		(bi = "OFF"), std::invalid_argument);
+
+	// Strict comparisons: int or string 0/1 values are int not bool
+	std::string s;
+	bi << "true";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value", (s == "yes"));
+
+	bi << false;
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value", (s == "no"));
+
+	bi << 1;
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => int)", (s == "1"));
+
+	bi = 0;
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => int)", (s == "0"));
+
+	bi = "1";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => int)", (s == "1"));
+
+	bi << "0";
+	s = bi.toString();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should get printed as expected string value (0/1 => int)", (s == "0"));
+
+	bi.clear();
+	CPPUNIT_ASSERT_MESSAGE("BoolInt should be not 'set()' after 'clear()", !(bi.set()));
+}
+
+void NutConfTest::testParseToken()
 {
     static const char* src =
         "Bonjour monde\n"
@@ -176,7 +553,7 @@ void NutConfTest::testPasreToken()
 
 }
 
-void NutConfTest::testPasreTokenWithoutColon()
+void NutConfTest::testParseTokenWithoutColon()
 {
     static const char* src =
         "Bonjour monde\n"
@@ -276,9 +653,9 @@ void NutConfTest::testUpsmonConfigParser()
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find SHUTDOWNCMD '/sbin/shutdown -h +0'", string("/sbin/shutdown -h +0"), *conf.shutdownCmd);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find NOTIFYCMD '/usr/local/ups/bin/notifyme'", string("/usr/local/ups/bin/notifyme"), *conf.notifyCmd);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find POWERDOWNFLAG '/etc/killpower'", string("/etc/killpower"), *conf.powerDownFlag);
-	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find POLLFREQ 30", 30u, *conf.poolFreq);
-	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find POLLFREQALERT 5", 5u, *conf.poolFreqAlert);
-	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find HOSTSYNC 15", 15u, *conf.hotSync);
+	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find POLLFREQ 30", 30u, *conf.pollFreq);
+	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find POLLFREQALERT 5", 5u, *conf.pollFreqAlert);
+	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find HOSTSYNC 15", 15u, *conf.hostSync);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find DEADTIME 15", 15u, *conf.deadTime);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find RBWARNTIME 43200", 43200u, *conf.rbWarnTime);
 	CPPUNIT_ASSERT_EQUAL_MESSAGE("Cannot find NOCOMMWARNTIME 300", 300u, *conf.noCommWarnTime);
@@ -343,3 +720,10 @@ void NutConfTest::testUpsdConfigParser()
 	}
 
 }
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
+#endif
diff --git a/tests/nutconf_ut.cpp b/tests/nutconf_ut.cpp
index ba8c8947d1..bff3ca74f0 100644
--- a/tests/nutconf_ut.cpp
+++ b/tests/nutconf_ut.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
         2012	Vaclav Krpec <VaclavKrpec@Eaton.com>
+        2024    Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -25,6 +26,43 @@
 #include "nutconf.hpp"
 #include "nutwriter.hpp"
 
+#include <algorithm>
+
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+#pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
+#  pragma GCC diagnostic ignored "-Wglobal-constructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
+#  pragma GCC diagnostic ignored "-Wexit-time-destructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
+#endif
+
 #include <cppunit/extensions/HelperMacros.h>
 
 /**
@@ -54,8 +92,19 @@ class NutConfigUnitTest: public CppUnit::TestFixture {
 	 *
 	 *  \param  config   Configuration object
 	 *  \param  content  Expected serialization
+	 *  \param  quote_sensitive  Flag to allow stripping double-quotes for fallback comparison
 	 */
-	void check(const nut::Serialisable * config, const std::string & content);
+	void check(const nut::Serialisable * config, const std::string & content, const bool quote_sensitive);
+
+	/**
+	 *  \brief  Check configuration serialization contents (exact)
+	 *
+	 *  \param  config   Configuration object
+	 *  \param  content  Expected serialization
+	 */
+	inline void check(const nut::Serialisable * config, const std::string & content) {
+		check(config, content, true);
+	}
 
 	public:
 
@@ -91,7 +140,7 @@ void NutConfigUnitTest::load(nut::Serialisable * config, const std::string & fil
 }
 
 
-void NutConfigUnitTest::check(const nut::Serialisable * config, const std::string & content) {
+void NutConfigUnitTest::check(const nut::Serialisable * config, const std::string & content, const bool quote_sensitive) {
 	nut::NutMemory mem;
 
 	CPPUNIT_ASSERT(config->writeTo(mem));
@@ -102,12 +151,24 @@ void NutConfigUnitTest::check(const nut::Serialisable * config, const std::strin
 
 	CPPUNIT_ASSERT(nut::NutStream::NUTS_OK == status);
 
-	if (content != str) {
-		std::cerr << "--- expected ---" << std::endl << content << "--- end ---" << std::endl;
-		std::cerr << "--- serialized ---" << std::endl << str << "--- end ---" << std::endl;
+	if (content == str)
+		return;
+
+	if (!quote_sensitive) {
+		// Re-check with quotes stripped (we output paths, passwords etc. quoted)
+		std::string uqStr = str, uqContent = content;
+		uqStr.erase(std::remove(uqStr.begin(), uqStr.end(), '"'), uqStr.end());
+		uqContent.erase(std::remove(uqContent.begin(), uqContent.end(), '"'), uqContent.end());
 
-		CPPUNIT_ASSERT_MESSAGE("Configuration serialization check failed", 0);
+		if (uqContent == uqStr)
+			return;
 	}
+
+	// Neither expectation was met
+	std::cerr << "--- expected ---" << std::endl << content << "--- end ---" << std::endl;
+	std::cerr << "--- serialized ---" << std::endl << str << "--- end ---" << std::endl;
+
+	CPPUNIT_ASSERT_MESSAGE("Configuration serialization check failed", 0);
 }
 
 
@@ -118,8 +179,15 @@ void NutConfigUnitTest::testNutConfiguration() {
 
 	config.mode = nut::NutConfiguration::MODE_STANDALONE;
 
+	config.upsdOptions   = "-DDD -B";
+	config.allowNoDevice = true;
+	config.poweroffQuiet = false;
+
 	check(static_cast<nut::Serialisable *>(&config),
 		"MODE=standalone\n"
+		"ALLOW_NO_DEVICE=true\n"
+		"UPSD_OPTIONS='-DDD -B'\n"
+		"POWEROFF_QUIET=false\n"
 	);
 }
 
@@ -132,20 +200,58 @@ void NutConfigUnitTest::testUpsmonConfiguration() {
 
 	config.shutdownCmd   = "/sbin/shutdown -h +2 'System shutdown in 2 minutes!'";
 	config.powerDownFlag = "/run/nut/killpower";
-	config.poolFreqAlert = 10;
+	config.pollFreqAlert = 10;
 	config.deadTime      = 30;
 
+	config.debugMin      = 6;
+
+	// Note different bool wording expected below
+	// and generally try different input types here.
+	// Hm, maybe we need typed constructors to init
+	// the values for test? ("new" weirdness below
+	// is due to Settable<> formal type mismatch)
+	config.shutdownExit  = (*(new nut::BoolInt()) << "true");
+	config.oblbDuration  = -1;
+	config.certVerify    = (*(new nut::BoolInt()) << false);
+	config.forceSsl      = (*(new nut::BoolInt()) << "1");
+
+	config.certIdent.certName    = "My test cert";
+	config.certIdent.certDbPass  = "DbPwd!";
+
+	nut::CertHost certHost;
+	certHost.host        = "remote:3493";
+	certHost.certName    = "NUT server cert";
+	certHost.certVerify  = (*(new nut::BoolInt()) << "true");
+	certHost.forceSsl    = (*(new nut::BoolInt()) << 0);
+	config.certHosts.push_back(certHost);
+
+	certHost.host        = "localhost:13493";
+	certHost.certName    = "My NUT server cert";
+	certHost.certVerify  = (*(new nut::BoolInt()) << "false");
+	certHost.forceSsl    = (*(new nut::BoolInt()) << false);
+	config.certHosts.push_back(certHost);
+
+	// Note: More config data points come from the file loaded above
 	check(static_cast<nut::Serialisable *>(&config),
+		"DEBUG_MIN 6\n"
 		"SHUTDOWNCMD \"/sbin/shutdown -h +2 'System shutdown in 2 minutes!'\"\n"
-		"POWERDOWNFLAG /run/nut/killpower\n"
+		"POWERDOWNFLAG \"/run/nut/killpower\"\n"
 		"MINSUPPLIES 1\n"
 		"POLLFREQ 5\n"
 		"POLLFREQALERT 10\n"
+		"OFFDURATION 30\n"
+		"OBLBDURATION -1\n"
+		"SHUTDOWNEXIT yes\n"
+		"CERTVERIFY 0\n"
+		"FORCESSL 1\n"
 		"HOSTSYNC 15\n"
 		"DEADTIME 30\n"
 		"RBWARNTIME 43200\n"
 		"NOCOMMWARNTIME 300\n"
 		"FINALDELAY 5\n"
+		"CERTIDENT \"My test cert\" \"DbPwd!\"\n"
+		"CERTHOST \"remote:3493\" \"NUT server cert\" 1 0\n"
+		"CERTHOST \"localhost:13493\" \"My NUT server cert\" 0 0\n"
 	);
 }
 
@@ -171,14 +277,15 @@ void NutConfigUnitTest::testUpsdConfiguration() {
 
 	config.listens.push_back(listen);
 
+	// NOTE: Three-arg check() here to retry (and succeed) with un-quoted paths
 	check(static_cast<nut::Serialisable *>(&config),
 		"MAXAGE 15\n"
 		"MAXCONN 1024\n"
-		"STATEPATH /var/run/nut\n"
+		"STATEPATH \"/var/run/nut\"\n"
 		"CERTFILE /usr/share/ssl-cert/ssleay.cnf\n"
 		"LISTEN 127.0.0.1 3493\n"
 		"LISTEN ::1 3493\n"
-	);
+	, false);
 }
 
 
@@ -193,15 +300,98 @@ void NutConfigUnitTest::testUpsConfiguration() {
 	config.setPort(my_ups, "/dev/ttyS0");
 	config.setDescription(my_ups, "Web server");
 
+	// IRL not for a serial-port UPS, but okay for tests;
+	// Note NUT v2.8.1 introduced these as "hexnum" values,
+	// but the strtoul() underneath knows to strip "0x" for
+	// base16 conversions - so can we write them either way:
+	config.setUsbConfigIndex(my_ups, 0x81);
+	config.setUsbHidDescIndex(my_ups, 0x3f);
+
 	// Note: "maxretry = 3" comes from current ups.conf.sample non-comment lines
-	check(static_cast<nut::Serialisable *>(&config),
+	std::string expected =
 		"maxretry = 3\n\n"
 		"[powerpal]\n"
 		"\tdesc = \"Web server\"\n"
 		"\tdriver = blazer_ser\n"
 		"\tport = /dev/ttyS0\n"
-		"\n"
-	);
+		"\tusb_config_index = 81\n"
+		"\tusb_hid_desc_index = 3f\n"
+		"\n";
+
+	check(static_cast<nut::Serialisable *>(&config), expected);
+
+	// Make sure we can parse back the "hexnum" entries correctly
+	config.parseFromString(expected);
+	check(static_cast<nut::Serialisable *>(&config), expected);
+
+	// Check that "0x" prefix (and/or quotes) do not matter on
+	// this platform (note that parsing results are strings from
+	// original input; for the check we interpret them as numbers
+	// and save back):
+	std::string input2 =
+		"maxretry = 3\n\n"
+		"[powerpal]\n"
+		"\tdesc = \"Web server\"\n"
+		"\tdriver = blazer_ser\n"
+		"\tport = /dev/ttyS0\n"
+		"\tusb_config_index = 0x81\n"
+		"\tusb_hid_desc_index = \"0x3f\"\n"
+		"\n";
+
+	config.parseFromString(input2);
+	config.setUsbConfigIndex (my_ups, config.getUsbConfigIndex(my_ups));
+	config.setUsbHidDescIndex(my_ups, config.getUsbHidDescIndex(my_ups));
+
+	// Should retrieve "-1" for unset value by default in its getter,
+	// and auto-destroy the (missing) entry upon set() because < 0
+	config.setUsbSetAltInterface (my_ups, config.getUsbSetAltInterface(my_ups));
+
+	check(static_cast<nut::Serialisable *>(&config), expected);
+
+	CPPUNIT_ASSERT_EQUAL(static_cast<long long int>(129),
+			config.getUsbConfigIndex(my_ups));
+	CPPUNIT_ASSERT_EQUAL(static_cast<long long int>(0x3f),
+			config.getUsbHidDescIndex(my_ups));
+
+	// Check default.* and override.* value(!) pre-sets:
+	std::string input3 =
+		"[powerpal]\n"
+		"\tdesc = \"Web server\"\n"
+		"\tdriver = blazer_ser\n"
+		"\tport = /dev/ttyS0\n"
+		"\tdefault.battery.voltage.high = 28.3\n"
+		"\n";
+
+	// "high" is inherited from input; "log" added by code:
+	std::string expected3 =
+		"[powerpal]\n"
+		"\tdefault.battery.voltage.high = 28.3\n"
+		"\tdesc = \"Web server\"\n"
+		"\tdriver = blazer_ser\n"
+		"\toverride.battery.voltage.low = 12.4\n"
+		"\tport = /dev/ttyS0\n"
+		"\n";
+
+	config.parseFromString(input3);
+	config.setOverrideDouble(my_ups, "battery.voltage.low", 12.4);
+
+	// "maxretry" is inherited from earlier content of config
+	// (not cleared). Maybe a bug, address later.
+	check(static_cast<nut::Serialisable *>(&config),
+		"maxretry = 3\n\n" + expected3);
+
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(28.3,
+			config.getDefaultDouble(my_ups, "battery.voltage.high"), 0.0001);
+	CPPUNIT_ASSERT_DOUBLES_EQUAL(12.4,
+			config.getOverrideDouble(my_ups, "battery.voltage.low"), 0.0001);
+
+	// TODO: Wipe method? Fix parse*() to clear global section
+	// like they do clear and repopulate an UPS section?
+	// Re-parse from scratch
+	nut::UpsConfiguration config3;
+	config3.parseFromString(input3);
+	config3.setOverrideDouble(my_ups, "battery.voltage.low", 12.4);
+	check(static_cast<nut::Serialisable *>(&config3), expected3);
 }
 
 
@@ -211,7 +401,7 @@ void NutConfigUnitTest::testUpsdUsersConfiguration() {
 	load(static_cast<nut::Serialisable *>(&config), ABS_TOP_SRCDIR "/conf/upsd.users.sample");
 
 	config.setPassword("upsmon", "ytrewq");
-	config.setUpsmonMode(nut::UpsdUsersConfiguration::UPSMON_MASTER);
+	config.setUpsmonMode(nut::UpsdUsersConfiguration::UPSMON_PRIMARY);
 
 	config.setPassword("admin", "qwerty=ui");
 	config.setActions("admin", nut::ConfigParamList(1, "SET"));
@@ -225,7 +415,7 @@ void NutConfigUnitTest::testUpsdUsersConfiguration() {
 		"\n"
 		"[upsmon]\n"
 		"\tpassword = ytrewq\n"
-		"\tupsmon master\n"
+		"\tupsmon primary\n"
 		"\n"
 	);
 }
@@ -235,3 +425,10 @@ void NutConfigUnitTest::testUpsdUsersConfiguration() {
 //   definitions; its vtable will be emitted in every translation unit
 //   [-Werror,-Wweak-vtables]
 NutConfigUnitTest::~NutConfigUnitTest() {}
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
+#endif
diff --git a/tests/nutipc_ut.cpp b/tests/nutipc_ut.cpp
index 9c49f0f0a7..16bfce9696 100644
--- a/tests/nutipc_ut.cpp
+++ b/tests/nutipc_ut.cpp
@@ -5,6 +5,10 @@
 
             \author Vaclav Krpec <VaclavKrpec@Eaton.com>
 
+        Copyright (C) 2024
+
+            \author Jim Klimov <jimklimov+nut@gmail.com>
+
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 2 of the License, or
@@ -25,8 +29,6 @@
 #include "nutipc.hpp"
 #include "nutstream.hpp"
 
-#include <cppunit/extensions/HelperMacros.h>
-
 #include <sstream>
 
 extern "C" {
@@ -37,6 +39,42 @@ extern "C" {
 extern bool verbose;
 }
 
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+#pragma GCC diagnostic push
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
+#  pragma GCC diagnostic ignored "-Wglobal-constructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS
+#  pragma GCC diagnostic ignored "-Wexit-time-destructors"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
+#  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push "-Wdeprecated-declarations"
+#endif
+
+#include <cppunit/extensions/HelperMacros.h>
 
 /**
  *  \brief  NUT IPC module unit test
@@ -305,3 +343,10 @@ void NutIPCUnitTest::testSignalRecvStaggered() {
 //   [-Werror,-Wweak-vtables]
 TestSignalHandler::~TestSignalHandler() {}
 NutIPCUnitTest::~NutIPCUnitTest() {}
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
+# pragma GCC diagnostic pop
+#endif
diff --git a/tests/nutstream_ut.cpp b/tests/nutstream_ut.cpp
index 918daa0c95..35e1608dba 100644
--- a/tests/nutstream_ut.cpp
+++ b/tests/nutstream_ut.cpp
@@ -3,6 +3,7 @@
 
     Copyright (C)
         2012	Vaclav Krpec <VaclavKrpec@Eaton.com>
+        2024	Jim Klimov <jimklimov+nut@gmail.com>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -45,8 +46,8 @@ extern "C" {
 extern bool verbose;
 }
 
-/* Current CPPUnit offends the honor of C++98 */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS)
+/* Current CPPUnit offends the honor of C++98 and maybe later versions */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
 #pragma GCC diagnostic push
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS
 #  pragma GCC diagnostic ignored "-Wglobal-constructors"
@@ -57,6 +58,24 @@ extern bool verbose;
 # ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS
 #  pragma GCC diagnostic ignored "-Wdeprecated-declarations"
 # endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wsuggest-destructor-override"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wweak-vtables"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wdeprecated-dynamic-exception-spec"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wextra-semi"
+# endif
+# ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC
+#  pragma GCC diagnostic ignored "-Wold-style-cast"
+# endif
 #endif
 #ifdef __clang__
 # pragma clang diagnostic push "-Wdeprecated-declarations"
@@ -469,6 +488,6 @@ NutStreamUnitTest::~NutStreamUnitTest() {}
 #ifdef __clang__
 # pragma clang diagnostic pop
 #endif
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS)
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXIT_TIME_DESTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_GLOBAL_CONSTRUCTORS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DECLARATIONS || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_SUGGEST_DESTRUCTOR_OVERRIDE_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_WEAK_VTABLES_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_DEPRECATED_DYNAMIC_EXCEPTION_SPEC_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_EXTRA_SEMI_BESIDEFUNC || defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_OLD_STYLE_CAST_BESIDEFUNC)
 # pragma GCC diagnostic pop
 #endif
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 97cdccf0f1..1321c3cf6a 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -3,11 +3,11 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 # SUBDIRS are explicitly a listing of all the directories that make
 # must recurse into BEFORE processing the current directory.
@@ -25,7 +25,7 @@ SUBDIRS = . nut-scanner nutconf
 PYTHON = @PYTHON@
 
 EXTRA_DIST = nut-usbinfo.pl nut-recorder.sh nut-ddl-dump.sh nut-dumpdiff.sh \
-  gitlog2changelog.py.in nut-snmpinfo.py.in driver-list-format.sh
+  gitlog2changelog.py.in gitlog2version.sh nut-snmpinfo.py.in driver-list-format.sh
 
 # These files are generated for nut-scanner builds (and cleaned as any others),
 # and can change as respective SNMP/USB subdriver sources are iterated by a
diff --git a/tools/gitlog2changelog.py.in b/tools/gitlog2changelog.py.in
index a5e4d78660..fca6f5ac96 100755
--- a/tools/gitlog2changelog.py.in
+++ b/tools/gitlog2changelog.py.in
@@ -10,6 +10,24 @@ from textwrap import TextWrapper
 import sys
 import subprocess
 
+# Python 3 compatibility hack
+try:
+    try:
+        import unicode
+    except:
+        # Maybe built-in?
+        pass
+    unicode('')
+except NameError as ex:
+    #DEBUG# sys.stderr.write("Using 'str' as 'unicode': %s\n" % str(ex))
+    #DEBUG# sys.stderr.flush()
+    unicode = str
+
+try:
+    import unicodedata
+except:
+    pass
+
 rev_range = "HEAD"
 
 if len(sys.argv) > 1:
@@ -71,6 +89,31 @@ else:
     else:
         fout = open(CHANGELOG_FILE, "w")
 
+# By default we collect information from a commit and output it as soon as
+# we have enough. Part of it is best-effort grouping of a series of commits
+# made by the same author on the same day, if they follow each other.
+# The alternative is to expend memory to collect all git log entries into a
+# dictionary first (key = date+author, value = list of entries) and only
+# print the output in the end of processing. This costs more resources, so
+# is not default behavior.
+requireGroupByDateAuthor = False
+try:
+    tmpEnvVar = os.environ.get("CHANGELOG_REQUIRE_GROUP_BY_DATE_AUTHOR", None)
+    if str(tmpEnvVar).lower() == "true":
+        requireGroupByDateAuthor = True
+except Exception as ignored:
+    pass
+
+cachedContent = None
+if requireGroupByDateAuthor:
+    try:
+        from collections import defaultdict
+        cachedContent = defaultdict(list)
+    except Exception as x:
+        print("Failed to init requireGroupByDateAuthor processing as defaultdict(list), trying simple dict(): " + str(x))
+        requireGroupByDateAuthor = False
+        cachedContent = dict()
+
 # Set up the loop variables in order to locate the blocks we want
 authorFound = False
 dateFound = False
@@ -81,6 +124,14 @@ messageNL = False
 files = ""
 prevAuthorLine = ""
 
+# Legacy default: keep as is
+authorMustBeASCII = False
+authorMustBeASCII_inverse_setting = str(os.environ.get("WITH_PDF_NONASCII_TITLES", "")).upper()
+if authorMustBeASCII_inverse_setting in ["YES", "TRUE"]:
+    authorMustBeASCII = False
+elif authorMustBeASCII_inverse_setting in ["NO", "FALSE"]:
+    authorMustBeASCII = True
+
 # See also: https://github.com/python/cpython/blob/main/Lib/textwrap.py
 wrapper = TextWrapper(initial_indent="\t", subsequent_indent="\t  ", break_on_hyphens=False, break_long_words=False)
 
@@ -104,6 +155,14 @@ for line in fin:
         try:
             author = authorList[1]
             author = author[0 : len(author) - fin_chop]
+            if authorMustBeASCII:
+                try:
+                    if isinstance(author, str) and unicode != str:
+                        author = unicodedata.normalize(u'NFKD', unicode(author, "utf-8")).encode('ascii', 'ignore').decode('utf8')
+                    else:
+                        author = unicodedata.normalize(u'NFKD', author).encode('ascii', 'ignore').decode('utf8')
+                except Exception as e:
+                    print("Could not unicodedata.normalize() author '%s': %s" % (author, str(e)))
             authorFound = True
         except:
             print("Could not parse authorList = '%s'" % (line))
@@ -128,7 +187,14 @@ for line in fin:
         continue
     # Extract the actual commit message for this commit
     elif authorFound and dateFound and messageFound is False:
-        # Find the commit message if we can
+        # Find the commit message if we can (including the optional
+        # details after the title and a blank line)
+        # FIXME: Detect end of message by /^#/ to allow for longer essays
+        #  in the detailed comments part?
+        # FIXME: Some such comments include asciidoc-ish markup, notably
+        #  bullet lists - do not concatenate those into one block but do
+        #  actually pass them as sub-lists (indented, and perhaps not
+        #  starting with an asterisk which we use for this document).
         if len(line) == fin_chop:
             if messageNL:
                 messageFound = True
@@ -153,21 +219,33 @@ for line in fin:
                 files = files + ", " + fileList[0].strip()
             else:
                 files = fileList[0].strip()
+
     # All of the parts of the commit have been found - write out the entry
     if authorFound and dateFound and messageFound and filesFound:
         # First the author line, only outputted if it is the first for that
-        # author on this day
+        # author on this day.
+        # WARNING: In case of git rebase commit shuffling, merges of dormant
+        # branches, etc. we are not guaranteed to have all dates in the list
+        # nicely ordered. In fact, the same date+author can be repeated if
+        # there were commits with other metadata in git history between those
+        # (e.g. many PRs from a few authors merged during one day). While we
+        # could cache each section by authorLine and only output in the end,
+        # it can require a lot of memory - so by default we do not.
         authorLine = date + "  " + author
-        if len(prevAuthorLine) == 0:
-            fout.write(authorLine + "\n\n")
-        elif authorLine == prevAuthorLine:
-            pass
+        if requireGroupByDateAuthor:
+            if authorLine not in cachedContent:
+                cachedContent[authorLine] = list()
         else:
-            fout.write("\n" + authorLine + "\n\n")
+            if len(prevAuthorLine) == 0:
+                fout.write(authorLine + "\n\n")
+            elif authorLine == prevAuthorLine:
+                pass
+            else:
+                fout.write("\n" + authorLine + "\n\n")
 
         # Assemble the actual commit message line(s) and limit the line length
         # to 80 characters.
-        # Avoid printing same (or equivalen) filename lists twice, if commit
+        # Avoid printing same (or equivalent) filename lists twice, if commit
         # message starts with them.
         if message.startswith(files + ":"):
             commitLine = "* " + message
@@ -185,8 +263,11 @@ for line in fin:
             else:
                 commitLine = "* " + files + ": " + message
 
-        # Write out the commit line
-        fout.write(wrapper.fill(commitLine) + "\n")
+        if requireGroupByDateAuthor:
+            cachedContent[authorLine].append(commitLine)
+        else:
+            # Write out the commit line, wrapped for length
+            fout.write(wrapper.fill(commitLine) + "\n")
 
         # Now reset all the variables ready for a new commit block.
         authorFound = False
@@ -198,6 +279,22 @@ for line in fin:
         files = ""
         prevAuthorLine = authorLine
 
+if requireGroupByDateAuthor:
+    # We did not print anything before, flush it out now;
+    # most recent date first (alphanumerically reverse)
+    counter = 0
+    for authorLine in sorted(cachedContent, reverse=True):
+        if counter == 0:
+            fout.write(authorLine + "\n\n")
+        else:
+            fout.write("\n" + authorLine + "\n\n")
+
+        # Use original list append order
+        for commitLine in cachedContent[authorLine]:
+            fout.write(wrapper.fill(commitLine) + "\n")
+
+        counter = counter + 1
+
 # Close the input and output lines now that we are finished.
 if fin_mode == 3:
     p.stdout.close()
diff --git a/tools/gitlog2version.sh b/tools/gitlog2version.sh
new file mode 100755
index 0000000000..5f0a834b4f
--- /dev/null
+++ b/tools/gitlog2version.sh
@@ -0,0 +1,287 @@
+#!/bin/sh
+
+# Copyright (C) 2016-2024 by Jim Klimov <jimklimov+nut@gmail.com>
+#
+#   This program is free software; you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation; either version 2 of the License, or
+#   (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program; if not, write to the Free Software
+#   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+############################################################################
+#
+# For setup check NUT_VERSION* in script source.
+#
+# Helper script to determine the project version in a manner similar to
+# what `git describe` produces, but with added numbers after the common
+# triplet of semantically versioned numbers:   X.Y.Z.T.B(-C-gHASH)
+#   * X: MAJOR - incompatible API changes
+#   * Y: MINOR - new features and/or API
+#   * Z: PATCH - small bug fixes
+#   * T: Commits on trunk since previous release tag
+#   * B: Commits on branch since nearest ancestor which is on trunk
+# The optional suffix (only for commits which are not tags themselves)
+# is provided by `git describe`:
+#   * C: Commits on branch since previous release tag
+#   * H: Git hash (prefixed by "g" character) of the described commit
+# Note that historically NUT did not diligently follow the semver triplet,
+# primarily because a snapshot of trunk is tested and released, and work
+# moves on with the PATCH part (rarely MINOR one) incremented; no actual
+# patches are released to some sustaining track of an older release lineage.
+# There were large re-designs that got MAJOR up to 2, though.
+#
+############################################################################
+# Checked with bash 3 and 5, dash, ksh, zsh and even busybox sh;
+# OpenIndiana, FreeBSD and OpenBSD sh. Not compatible with csh and tcsh.
+# See some examples in https://github.com/networkupstools/nut/issues/1949
+
+LANG=C
+LC_ALL=C
+TZ=UTC
+export LANG LC_ALL TZ
+
+if [ x"${abs_top_srcdir}" = x ]; then
+    SCRIPT_DIR="`dirname "$0"`"
+    SCRIPT_DIR="`cd "${SCRIPT_DIR}" && pwd`"
+    abs_top_srcdir="${SCRIPT_DIR}/.."
+fi
+if [ x"${abs_top_builddir}" = x ]; then
+    abs_top_builddir="${abs_top_srcdir}"
+fi
+
+############################################################################
+# Numeric-only default version, for AC_INIT and similar consumers
+# in case we build without a Git workspace (from tarball, etc.)
+# By legacy convention, 3-digit "semver" was for NUT releases, and
+# a nominal "semver.1" for any development snapshots afterwards.
+
+# The VERSION_DEFAULT files are absent in Git, but should be provided
+# in tarballs. It may be re-generated by NUT autogen.sh script forcibly,
+# but is otherwise preferred if present and NUT source dir is not a git
+# workspace itself (e.g. when we build from release tarballs in
+# a git-tracked repository of distro recipes, do not use that
+# distro's own versions for NUT).
+# Embedded distros that hack a NUT version are not encouraged to, but
+# can, use a NUT_VERSION_FORCED variable or a VERSION_FORCED file with
+# higher priority than auto-detection attempts. Unfortunately, some
+# appliances tag all software the same with their firmware version;
+# if this is required, a (NUT_)VERSION_FORCED_SEMVER envvar or file can
+# help identify the actual NUT release version triplet used on the box.
+# Please use it, it immensely helps with community troubleshooting!
+if [ -s "${abs_top_srcdir}/VERSION_FORCED" ] ; then
+    . "${abs_top_srcdir}/VERSION_FORCED" || exit
+fi
+if [ -s "${abs_top_srcdir}/VERSION_FORCED_SEMVER" ] ; then
+    . "${abs_top_srcdir}/VERSION_FORCED_SEMVER" || exit
+fi
+if [ -n "${NUT_VERSION_FORCED-}" ] ; then
+    NUT_VERSION_DEFAULT="${NUT_VERSION_FORCED-}"
+    NUT_VERSION_PREFER_GIT=false
+fi
+
+if [ -z "${NUT_VERSION_DEFAULT-}" -a -s "${abs_top_builddir}/VERSION_DEFAULT" ] ; then
+    . "${abs_top_builddir}/VERSION_DEFAULT" || exit
+    [ x"${NUT_VERSION_PREFER_GIT-}" = xtrue ] || { [ -e "${abs_top_srcdir}/.git" ] || NUT_VERSION_PREFER_GIT=false ; }
+fi
+
+if [ -z "${NUT_VERSION_DEFAULT-}" -a -s "${abs_top_srcdir}/VERSION_DEFAULT" ] ; then
+    . "${abs_top_srcdir}/VERSION_DEFAULT" || exit
+    [ x"${NUT_VERSION_PREFER_GIT-}" = xtrue ] || { [ -e "${abs_top_srcdir}/.git" ] || NUT_VERSION_PREFER_GIT=false ; }
+fi
+
+# Fallback default, to be updated only during release cycle
+[ -n "${NUT_VERSION_DEFAULT-}" ] || NUT_VERSION_DEFAULT='2.8.2.1'
+
+# Default website paths, extended for historic sub-sites for a release
+[ -n "${NUT_WEBSITE-}" ] || NUT_WEBSITE="https://www.networkupstools.org/"
+
+# Must be "true" or "false" exactly, interpreted as such below:
+[ x"${NUT_VERSION_PREFER_GIT-}" = xfalse ] || { [ -e "${abs_top_srcdir}/.git" ] && NUT_VERSION_PREFER_GIT=true || NUT_VERSION_PREFER_GIT=false ; }
+
+getver_git() {
+    # NOTE: The chosen trunk branch must be up to date (may be "origin/master"
+    # or "upstream/master", etc.) for resulting version discovery to make sense.
+    if [ x"${NUT_VERSION_GIT_TRUNK-}" = x ] ; then
+        # Find the newest info, it may be in a fetched branch
+        # not yet checked out locally (or long not updated).
+        # Currently we repeat the likely branch names in the
+        # end, so that if they exist and are still newest -
+        # those are the names to report.
+        for T in master `git branch -a 2>/dev/null | grep -E '^ *remotes/[^ ]*/master$'` origin/master upstream/master master ; do
+            git log -1 "$T" 2>/dev/null >/dev/null || continue
+            if [ x"${NUT_VERSION_GIT_TRUNK-}" = x ] ; then
+                NUT_VERSION_GIT_TRUNK="$T"
+            else
+                # T is strictly same or newer
+                # Assume no deviations from the one true path in a master branch
+                git merge-base --is-ancestor "${NUT_VERSION_GIT_TRUNK}" "${T}" 2>/dev/null >/dev/null \
+                && NUT_VERSION_GIT_TRUNK="$T"
+            fi
+        done
+        if [ x"${NUT_VERSION_GIT_TRUNK-}" = x ] ; then
+            echo "$0: FAILED to discover a NUT_VERSION_GIT_TRUNK in this workspace" >&2
+            return 1
+        fi
+    fi
+
+    # By default, only annotated tags are considered
+    ALL_TAGS_ARG=""
+    if [ x"${NUT_VERSION_GIT_ALL_TAGS-}" = xtrue ] ; then ALL_TAGS_ARG="--tags" ; fi
+
+    # NOTE: "--always" should not be needed in NUT repos normally,
+    # but may help other projects who accept such scheme and script:
+    # it tells git to return a commit hash if no tag is matched.
+    # It may still be needed on CI systems which only fetch the
+    # commit they build and no branch names or tags (minimizing the
+    # traffic, storage and general potential for creative errors).
+    ALWAYS_DESC_ARG=""
+    if [ x"${NUT_VERSION_GIT_ALWAYS_DESC-}" = xtrue ] ; then ALWAYS_DESC_ARG="--always" ; fi
+
+    # Praises to old gits and the new, who may --exclude:
+    DESC="`git describe $ALL_TAGS_ARG $ALWAYS_DESC_ARG --match 'v[0-9]*.[0-9]*.[0-9]' --exclude '*-signed' --exclude '*rc*' --exclude '*alpha*' --exclude '*beta*' --exclude '*Windows*' --exclude '*IPM*' 2>/dev/null`" \
+    && [ -n "${DESC}" ] \
+    || DESC="`git describe $ALL_TAGS_ARG $ALWAYS_DESC_ARG | grep -Ev '(rc|-signed|alpha|beta|Windows|IPM)' | grep -E 'v[0-9]*.[0-9]*.[0-9]'`"
+    # Old stripper (also for possible refspec parts like "tags/"):
+    #   echo "${DESC}" | sed -e 's/^v\([0-9]\)/\1/' -e 's,^.*/,,'
+    if [ x"${DESC}" = x ] ; then echo "$0: FAILED to 'git describe' this codebase" >&2 ; return 1 ; fi
+
+    # How much of the known trunk history is in current HEAD?
+    # e.g. all of it when we are on that branch or PR made from its tip,
+    # some of it if looking at a historic snapshot, or nothing if looking
+    # at the tagged commit (it is the merge base for itself and any of
+    # its descendants):
+    BASE="`git merge-base HEAD "${NUT_VERSION_GIT_TRUNK}"`" || BASE=""
+    if [ x"${BASE}" = x ] ; then echo "$0: FAILED to get a git merge-base of this codebase vs. '${NUT_VERSION_GIT_TRUNK}'" >&2 ; DESC=""; return  1; fi
+
+    # Nearest (annotated by default) tag preceding the HEAD in history:
+    TAG="`echo "${DESC}" | sed 's/-[0-9][0-9]*-g[0-9a-fA-F][0-9a-fA-F]*$//'`"
+
+    # Commit count since the tag and hash of the HEAD commit;
+    # empty e.g. when HEAD is the tagged commit:
+    SUFFIX="`echo "${DESC}" | sed 's/^.*\(-[0-9][0-9]*-g[0-9a-fA-F][0-9a-fA-F]*\)$/\1/'`" && [ x"${SUFFIX}" != x"${TAG}" ] || SUFFIX=""
+
+    # 5-digit version, note we strip leading "v" from the expected TAG value
+    VER5="${TAG#v}.`git log --oneline "${TAG}..${BASE}" | wc -l | tr -d ' '`.`git log --oneline "${NUT_VERSION_GIT_TRUNK}..HEAD" | wc -l | tr -d ' '`"
+    DESC5="${VER5}${SUFFIX}"
+
+    # Strip up to two trailing zeroes for trunk snapshots and releases
+    VER50="`echo "${VER5}" | sed -e 's/\.0$//' -e 's/\.0$//'`"
+    DESC50="${VER50}${SUFFIX}"
+
+    # Leave exactly 3 components
+    if [ -n "${NUT_VERSION_FORCED_SEMVER-}" ] ; then
+        SEMVER="${NUT_VERSION_FORCED_SEMVER-}"
+    else
+        SEMVER="`echo "${VER5}" | sed -e 's/^\([0-9][0-9]*\.[0-9][0-9]*\.[0-9][0-9]*\)\..*$/\1/'`"
+    fi
+    # FIXME? Add ".0" up to 3 components?
+}
+
+getver_default() {
+    NUT_VERSION_DEFAULT_DOTS="`echo "${NUT_VERSION_DEFAULT}" | sed 's/[^.]*//g' | tr -d '\n' | wc -c`"
+
+    # Ensure at least 4 dots (5 presumed-numeric components)
+    NUT_VERSION_DEFAULT5_DOTS="${NUT_VERSION_DEFAULT_DOTS}"
+    NUT_VERSION_DEFAULT5="${NUT_VERSION_DEFAULT}"
+    while [ "${NUT_VERSION_DEFAULT5_DOTS}" -lt 4 ] ; do
+        NUT_VERSION_DEFAULT5="${NUT_VERSION_DEFAULT5}.0"
+        NUT_VERSION_DEFAULT5_DOTS="`expr $NUT_VERSION_DEFAULT5_DOTS + 1`"
+    done
+
+    # Truncate/extend to exactly 2 dots (3 presumed-numeric components)
+    NUT_VERSION_DEFAULT3_DOTS="${NUT_VERSION_DEFAULT_DOTS}"
+    NUT_VERSION_DEFAULT3="${NUT_VERSION_DEFAULT}"
+    while [ "${NUT_VERSION_DEFAULT3_DOTS}" -lt 2 ] ; do
+        NUT_VERSION_DEFAULT3="${NUT_VERSION_DEFAULT3}.0"
+        NUT_VERSION_DEFAULT3_DOTS="`expr $NUT_VERSION_DEFAULT3_DOTS + 1`"
+    done
+    while [ "${NUT_VERSION_DEFAULT3_DOTS}" -gt 2 ] ; do
+        NUT_VERSION_DEFAULT3="`echo "${NUT_VERSION_DEFAULT3}" | sed 's,\.[0-9][0-9]*$,,'`"
+        NUT_VERSION_DEFAULT3_DOTS="`expr $NUT_VERSION_DEFAULT3_DOTS - 1`"
+    done
+
+    DESC5="${NUT_VERSION_DEFAULT5}"
+    DESC50="${NUT_VERSION_DEFAULT}"
+    VER5="${NUT_VERSION_DEFAULT5}"
+    VER50="${NUT_VERSION_DEFAULT}"
+    SUFFIX=""
+    BASE=""
+    if [ -n "${NUT_VERSION_FORCED_SEMVER-}" ] ; then
+        SEMVER="${NUT_VERSION_FORCED_SEMVER-}"
+    else
+        SEMVER="${NUT_VERSION_DEFAULT3}"
+    fi
+    TAG="v${NUT_VERSION_DEFAULT3}"
+}
+
+report_debug() {
+    # Debug
+    echo "SEMVER=${SEMVER}; TRUNK='${NUT_VERSION_GIT_TRUNK-}'; BASE='${BASE}'; DESC='${DESC}' => TAG='${TAG}' + SUFFIX='${SUFFIX}' => VER5='${VER5}' => VER50='${VER50}' => DESC50='${DESC50}'" >&2
+}
+
+report_output() {
+    case "${NUT_VERSION_QUERY-}" in
+        "DESC5")	echo "${DESC5}" ;;
+        "DESC50")	echo "${DESC50}" ;;
+        "VER5") 	echo "${VER5}" ;;
+        "VER50")	echo "${VER50}" ;;
+        "SEMVER")	echo "${SEMVER}" ;;
+        "IS_RELEASE")	[ x"${SEMVER}" = x"${VER50}" ] && echo true || echo false ;;
+        "TAG")  	echo "${TAG}" ;;
+        "SUFFIX")	echo "${SUFFIX}" ;;
+        "BASE") 	echo "${BASE}" ;;
+        "URL")
+            # Clarify the project website URL - particularly historically
+            # frozen snapshots made for releases
+            if [ x"${SEMVER}" = x"${VER50}" ] ; then
+                echo "${NUT_WEBSITE}historic/v${SEMVER}/index.html"
+            else
+                echo "${NUT_WEBSITE}"
+            fi
+            ;;
+        "UPDATE_FILE")
+            if [ x"${abs_top_builddir}" != x"${abs_top_srcdir}" ] \
+            && [ -s "${abs_top_srcdir}/VERSION_DEFAULT" ] \
+            && [ ! -s "${abs_top_builddir}/VERSION_DEFAULT" ] \
+            ; then
+                cp -f "${abs_top_srcdir}/VERSION_DEFAULT" "${abs_top_builddir}/VERSION_DEFAULT" || exit
+            fi
+
+            echo "NUT_VERSION_DEFAULT='${DESC50}'" > "${abs_top_builddir}/VERSION_DEFAULT.tmp" || exit
+            if cmp "${abs_top_builddir}/VERSION_DEFAULT.tmp" "${abs_top_builddir}/VERSION_DEFAULT" >/dev/null 2>/dev/null ; then
+                rm -f "${abs_top_builddir}/VERSION_DEFAULT.tmp"
+            else
+                mv -f "${abs_top_builddir}/VERSION_DEFAULT.tmp" "${abs_top_builddir}/VERSION_DEFAULT" || exit
+            fi
+            cat "${abs_top_builddir}/VERSION_DEFAULT"
+            ;;
+        *)		echo "${DESC50}" ;;
+    esac
+}
+
+DESC=""
+if $NUT_VERSION_PREFER_GIT ; then
+    if (command -v git && git rev-parse --show-toplevel) >/dev/null 2>/dev/null ; then
+        getver_git || { echo "$0: Fall back to pre-set default version information" >&2 ; DESC=""; }
+    fi
+fi
+
+if [ x"$DESC" = x ]; then
+    getver_default
+fi
+
+report_debug
+report_output
+
+# Set exit code based on availability of default version info data point
+# Not empty means good
+# TOTHINK: consider the stdout of report_output() instead?
+[ x"${DESC50}" != x ]
diff --git a/tools/nut-scanner/Makefile.am b/tools/nut-scanner/Makefile.am
index 4ed34f7214..0aa53d8342 100644
--- a/tools/nut-scanner/Makefile.am
+++ b/tools/nut-scanner/Makefile.am
@@ -3,14 +3,16 @@
 # Export certain values for ccache which NUT ci_build.sh can customize,
 # to facilitate developer iteration re-runs of "make" later.
 # At least GNU and BSD make implementations are okay with this syntax.
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_DIR=@CCACHE_DIR@
-@NUT_AM_MAKE_CAN_EXPORT@export CCACHE_PATH=@CCACHE_PATH@
-@NUT_AM_MAKE_CAN_EXPORT@export PATH=@PATH_DURING_CONFIGURE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
 
 # Generally, list headers and/or sources which are re-generated
 # for nut-scanner in the parent dir
+# Note there is also a libupsclient-version.h which we ensure and
+# manage via usual `make` dependencies below.
 NUT_SCANNER_DEPS_H = nutscan-usb.h nutscan-snmp.h
 NUT_SCANNER_DEPS_C =
 
@@ -28,7 +30,10 @@ $(NUT_SCANNER_DEPS): dummy
 
 # Make sure out-of-dir dependencies exist (especially when dev-building parts):
 $(top_builddir)/include/nut_version.h \
-$(top_builddir)/common/libcommonclient.la \
+$(top_builddir)/clients/libupsclient-version.h \
+$(top_builddir)/common/libnutwincompat.la \
+$(top_builddir)/drivers/libserial-nutscan.la \
+$(top_builddir)/common/libcommonstr.la \
 $(top_builddir)/common/libcommon.la: dummy
 	+@cd $(@D) && $(MAKE) $(AM_MAKEFLAGS) $(@F)
 
@@ -37,50 +42,45 @@ $(top_builddir)/common/libcommon.la: dummy
 # BUILT_SOURCES (in ../include) will ensure nut_version.h will
 # be built before anything else
 nut-scanner.c: $(top_builddir)/include/nut_version.h
+nutscan-init.c: $(top_builddir)/clients/libupsclient-version.h
 
-LINKED_SOURCE_FILES =
+# We optionally append values to this below
+bin_PROGRAMS =
+lib_LTLIBRARIES =
+include_HEADERS =
+dist_noinst_HEADERS =
 
-# Separate the .deps of other dirs from this one
-# NOTE: Not using "$<" due to a legacy Sun/illumos dmake bug with resolver
-# of dynamic vars, see e.g. https://man.omnios.org/man1/make#BUGS
-LINKED_SOURCE_FILES += serial.c
-serial.c: $(top_srcdir)/drivers/serial.c
-	test -s "$@" || ln -s -f "$(top_srcdir)/drivers/serial.c" "$@"
-
-LINKED_SOURCE_FILES += bcmxcp_ser.c
-bcmxcp_ser.c: $(top_srcdir)/drivers/bcmxcp_ser.c
-	test -s "$@" || ln -s -f "$(top_srcdir)/drivers/bcmxcp_ser.c" "$@"
-
-CLEANFILES += $(LINKED_SOURCE_FILES)
-BUILT_SOURCES += $(LINKED_SOURCE_FILES)
-
-# Note: we only build nut-scanner, and its library, if libltdl was found (required!)
+# Note: we only build nut-scanner, and its library, if libltdl was found (required ATM!)
 if WITH_NUT_SCANNER
- bin_PROGRAMS = nut-scanner
- lib_LTLIBRARIES = libnutscan.la
+ bin_PROGRAMS += nut-scanner
+ lib_LTLIBRARIES += libnutscan.la
 endif WITH_NUT_SCANNER
 libnutscan_la_SOURCES = scan_nut.c scan_nut_simulation.c scan_ipmi.c \
 			nutscan-device.c nutscan-ip.c nutscan-display.c \
 			nutscan-init.c scan_usb.c scan_snmp.c scan_xml_http.c \
 			scan_avahi.c scan_eaton_serial.c nutscan-serial.c
-nodist_libnutscan_la_SOURCES = $(LINKED_SOURCE_FILES)
 libnutscan_la_LIBADD = $(NETLIBS)
+libnutscan_la_LIBADD += $(top_builddir)/drivers/libserial-nutscan.la
+
 if WITH_LIBLTDL
 libnutscan_la_LIBADD += $(LIBLTDL_LIBS)
 endif WITH_LIBLTDL
-libnutscan_la_LIBADD += $(top_builddir)/common/libcommonclient.la
+
 if HAVE_SEMAPHORE_LIBS
 # Are additional libraries needed for semaphore support?
 libnutscan_la_LIBADD += $(SEMLIBS)
 endif HAVE_SEMAPHORE_LIBS
 
-# FIXME: From old ages onward, SERLIBS are added here and not in LIBADD... why?
-libnutscan_la_LDFLAGS = $(SERLIBS)
+libnutscan_la_LIBADD += $(SERLIBS)
 
+libnutscan_la_LDFLAGS =
 if HAVE_WINDOWS
   # Many versions of MingW seem to fail to build non-static DLL without this
+  libnutscan_la_LIBADD += $(top_builddir)/common/libnutwincompat.la
   libnutscan_la_LDFLAGS += -no-undefined
 endif HAVE_WINDOWS
+# Technically, we might only have this one set on Windows so far...
+libnutscan_la_LDFLAGS += @NETLIBS_GETADDRS@
 
 #
 # Below we set API versions of public libraries
@@ -89,7 +89,7 @@ endif HAVE_WINDOWS
 # object .so names would differ)
 #
 # libnutscan version information
-libnutscan_la_LDFLAGS += -version-info 2:5:0
+libnutscan_la_LDFLAGS += -version-info 2:6:0
 
 # libnutscan exported symbols regex
 # WARNING: Since the library includes parts of libcommon (as much as needed
@@ -100,12 +100,18 @@ libnutscan_la_LDFLAGS += -version-info 2:5:0
 # copies of "nut_debug_level" making fun of our debug-logging attempts.
 # One solution to tackle if needed for those cases would be to make some
 # dynamic/shared libnutcommon (etc.)
-libnutscan_la_LDFLAGS += -export-symbols-regex '^(nutscan_|nut_debug_level|s_upsdebugx|max_threads|curr_threads|nut_report_config_flags|upsdebugx_report_search_paths|nut_prepare_search_paths)'
-libnutscan_la_CFLAGS = -I$(top_srcdir)/clients -I$(top_srcdir)/include \
+libnutscan_la_LDFLAGS += -export-symbols-regex '^(nutscan_|nut_debug_level|s_upsdebug|fatalx|fatal_with_errno|xcalloc|xbasename|snprintfcat|max_threads|curr_threads|nut_report_config_flags|upsdebugx_report_search_paths|nut_prepare_search_paths|print_banner_once)'
+libnutscan_la_CFLAGS = \
+			-I$(top_builddir)/clients -I$(top_srcdir)/clients \
+			-I$(top_builddir)/include -I$(top_srcdir)/include \
 			$(LIBLTDL_CFLAGS) -I$(top_srcdir)/drivers
 
+libnutscan_la_LIBADD += $(top_builddir)/common/libcommonstr.la
+
 nut_scanner_SOURCES = nut-scanner.c
-nut_scanner_CFLAGS = -I$(top_srcdir)/clients -I$(top_srcdir)/include
+nut_scanner_CFLAGS = \
+			-I$(top_builddir)/clients -I$(top_srcdir)/clients \
+			-I$(top_builddir)/include -I$(top_srcdir)/include
 nut_scanner_LDADD = libnutscan.la
 
 if WITH_SSL
@@ -118,6 +124,9 @@ endif WITH_USB
 # Note: do not indent automake "if" lines
 if WITH_SNMP
   libnutscan_la_CFLAGS += $(LIBNETSNMP_CFLAGS)
+if !WITH_OPENSSL
+  libnutscan_la_CFLAGS += -UNETSNMP_USE_OPENSSL
+endif !WITH_OPENSSL
 if    WITH_SNMP_STATIC
     # MinGW builds of libnetsnmp are static-only, so we link it in:
     libnutscan_la_CFLAGS += -DWITH_SNMP_STATIC=1
@@ -143,11 +152,11 @@ if WITH_IPMI
 endif WITH_IPMI
 
 # C is not a header, but there is no dist_noinst_SOURCES
-dist_noinst_HEADERS = $(NUT_SCANNER_DEPS_H) $(NUT_SCANNER_DEPS_C)
+dist_noinst_HEADERS += $(NUT_SCANNER_DEPS_H) $(NUT_SCANNER_DEPS_C)
 
 # Optionally deliverable as part of NUT public API:
 if WITH_DEV
- include_HEADERS = nut-scan.h nutscan-device.h nutscan-ip.h nutscan-init.h nutscan-serial.h
+ include_HEADERS += nut-scan.h nutscan-device.h nutscan-ip.h nutscan-init.h nutscan-serial.h
 else !WITH_DEV
  dist_noinst_HEADERS += nut-scan.h nutscan-device.h nutscan-ip.h nutscan-init.h nutscan-serial.h
 endif !WITH_DEV
diff --git a/tools/nut-scanner/nut-scan.h b/tools/nut-scanner/nut-scan.h
index 3bba701369..4d481b24d5 100644
--- a/tools/nut-scanner/nut-scan.h
+++ b/tools/nut-scanner/nut-scan.h
@@ -70,12 +70,44 @@
 #ifdef HAVE_PTHREAD
 # include <pthread.h>
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 #  include <semaphore.h>
 # endif
 
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
-extern size_t max_threads, curr_threads, max_threads_netxml, max_threads_oldnut, max_threads_netsnmp;
+# ifdef HAVE_SEMAPHORE_NAMED
+#  ifdef HAVE_FCNTL_H
+#   include <fcntl.h>           /* For O_* constants with sem_open() */
+#  endif
+#  ifdef SYS_STAT_H
+#   include <sys/stat.h>        /* For mode constants */
+#  endif
+# endif
+#endif
+
+#ifdef __cplusplus
+/* *INDENT-OFF* */
+extern "C" {
+/* *INDENT-ON* */
+#endif
+
+#ifdef HAVE_PTHREAD
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+extern size_t max_threads, curr_threads, max_threads_netxml, max_threads_oldnut, max_threads_netsnmp, max_threads_ipmi;
+# endif
+
+# if defined HAVE_SEMAPHORE_UNNAMED
+#  define REPORT_SEM_INIT_METHOD	"sem_init"
+# elif defined HAVE_SEMAPHORE_NAMED
+#  define REPORT_SEM_INIT_METHOD	"sem_open"
+# endif
+
+# ifdef HAVE_SEMAPHORE_NAMED
+#  define SEMNAME_TOPLEVEL	"/libnutscan-toplevel-bus-scans"
+#  define SEMNAME_NETXML	"/libnutscan-netxml"
+#  define SEMNAME_UPSCLIENT	"/libnutscan-upsclient"
+#  define SEMNAME_EATON_SERIAL	"/libnutscan-eaton-serial"
+#  define SEMNAME_SNMP		"/libnutscan-snmp"
+#  define SEMNAME_IPMI		"/libnutscan-ipmi"
 # endif
 
 # ifdef HAVE_PTHREAD_TRYJOIN
@@ -88,12 +120,6 @@ typedef struct nutscan_thread {
 } nutscan_thread_t;
 #endif /* HAVE_PTHREAD */
 
-#ifdef __cplusplus
-/* *INDENT-OFF* */
-extern "C" {
-/* *INDENT-ON* */
-#endif
-
 /* SNMP structure */
 typedef struct nutscan_snmp {
 	char * community;
@@ -108,29 +134,30 @@ typedef struct nutscan_snmp {
 } nutscan_snmp_t;
 
 /* IPMI structure */
-/* Settings for OutofBand (remote) connection */
+/* Settings for Out-of-Band (remote) connection */
 typedef struct nutscan_ipmi {
-	char*			username;            /* IPMI 1.5 and 2.0 */
-	char*			password;            /* IPMI 1.5 and 2.0 */
-	int				authentication_type; /* IPMI 1.5 */
-	int				cipher_suite_id;     /* IPMI 2.0 */
-	char*			K_g_BMC_key;         /* IPMI 2.0, optional key for 2 key auth. */
-	int				privilege_level;     /* for both */
+	char*		username;            /* IPMI 1.5 and 2.0 */
+	char*		password;            /* IPMI 1.5 and 2.0 */
+	int		authentication_type; /* IPMI 1.5 */
+	int		cipher_suite_id;     /* IPMI 2.0 */
+	char*		K_g_BMC_key;         /* IPMI 2.0, optional key for 2 key auth. */
+	int		privilege_level;     /* for both */
 	unsigned int	workaround_flags;    /* for both */
-	int				ipmi_version;        /* IPMI 1.5 or 2.0? */
+	int		ipmi_version;        /* IPMI 1.5 or 2.0? */
+	char*		peername;            /* Hostname or IP for remote scans, NULL for local device bus (populated by scanning methods) */
 } nutscan_ipmi_t;
 
 /* IPMI auth defines, simply using FreeIPMI defines */
 #ifndef IPMI_AUTHENTICATION_TYPE_NONE
-  #define IPMI_AUTHENTICATION_TYPE_NONE                  0x00
-  #define IPMI_AUTHENTICATION_TYPE_MD2                   0x01
-  #define IPMI_AUTHENTICATION_TYPE_MD5                   0x02
-  #define IPMI_AUTHENTICATION_TYPE_STRAIGHT_PASSWORD_KEY 0x04
-  #define IPMI_AUTHENTICATION_TYPE_OEM_PROP              0x05
-  #define IPMI_AUTHENTICATION_TYPE_RMCPPLUS              0x06
+# define IPMI_AUTHENTICATION_TYPE_NONE                  0x00
+# define IPMI_AUTHENTICATION_TYPE_MD2                   0x01
+# define IPMI_AUTHENTICATION_TYPE_MD5                   0x02
+# define IPMI_AUTHENTICATION_TYPE_STRAIGHT_PASSWORD_KEY 0x04
+# define IPMI_AUTHENTICATION_TYPE_OEM_PROP              0x05
+# define IPMI_AUTHENTICATION_TYPE_RMCPPLUS              0x06
 #endif /* IPMI_AUTHENTICATION_TYPE_NONE */
 #ifndef IPMI_PRIVILEGE_LEVEL_ADMIN
-  #define IPMI_PRIVILEGE_LEVEL_ADMIN                     0x04
+# define IPMI_PRIVILEGE_LEVEL_ADMIN                     0x04
 #endif /* IPMI_PRIVILEGE_LEVEL_ADMIN */
 
 #define IPMI_1_5		1
@@ -160,28 +187,33 @@ typedef struct nutscan_usb {
 
 /* Scanning */
 nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip, useconds_t usec_timeout, nutscan_snmp_t * sec);
+nutscan_device_t * nutscan_scan_ip_range_snmp(nutscan_ip_range_list_t * irl, useconds_t usec_timeout, nutscan_snmp_t * sec);
 
 nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts);
 
 /* If "ip" == NULL, do a broadcast scan */
 /* If sec->usec_timeout <= 0 then the common usec_timeout arg overrides it */
 nutscan_device_t * nutscan_scan_xml_http_range(const char *start_ip, const char *end_ip, useconds_t usec_timeout, nutscan_xml_t * sec);
+nutscan_device_t * nutscan_scan_ip_range_xml_http(nutscan_ip_range_list_t * irl, useconds_t usec_timeout, nutscan_xml_t * sec);
 
 nutscan_device_t * nutscan_scan_nut(const char * startIP, const char * stopIP, const char * port, useconds_t usec_timeout);
+nutscan_device_t * nutscan_scan_ip_range_nut(nutscan_ip_range_list_t * irl, const char * port, useconds_t usec_timeout);
 
 nutscan_device_t * nutscan_scan_nut_simulation(void);
 
 nutscan_device_t * nutscan_scan_avahi(useconds_t usec_timeout);
 
 nutscan_device_t * nutscan_scan_ipmi(const char * startIP, const char * stopIP, nutscan_ipmi_t * sec);
+nutscan_device_t * nutscan_scan_ip_range_ipmi(nutscan_ip_range_list_t * irl, nutscan_ipmi_t * sec);
 
 nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_list);
 
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
-/* Expose shared libnutscanner semaphore for overall thread count
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+/* Expose shared libnutscan semaphore for overall thread count
  * limited across different scanning methods (protocols/media): */
 sem_t * nutscan_semaphore(void);
+void nutscan_semaphore_set(sem_t *s);
 # endif
 #endif
 
diff --git a/tools/nut-scanner/nut-scanner.c b/tools/nut-scanner/nut-scanner.c
index 500b3d9d59..c0f56ae05e 100644
--- a/tools/nut-scanner/nut-scanner.c
+++ b/tools/nut-scanner/nut-scanner.c
@@ -1,7 +1,8 @@
 /*
  *  Copyright (C) 2011 - 2024  Arnaud Quette <arnaud.quette@free.fr>
  *  Copyright (C) 2016 Michal Vyskocil <MichalVyskocil@eaton.com>
- *  Copyright (C) 2016 - 2023 Jim Klimov <EvgenyKlimov@eaton.com>
+ *  Copyright (C) 2016 - 2021 Jim Klimov <EvgenyKlimov@eaton.com>
+ *  Copyright (C) 2022 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -23,6 +24,7 @@
     \author Arnaud Quette <arnaud.quette@free.fr>
     \author Michal Vyskocil <MichalVyskocil@eaton.com>
     \author Jim Klimov <EvgenyKlimov@eaton.com>
+    \author Jim Klimov <jimklimov+nut@gmail.com>
 */
 
 #include "common.h"	/* Must be first include to pull "config.h" */
@@ -30,17 +32,46 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
-#include "nut_version.h"
 #include <unistd.h>
 #include <string.h>
 
+/* Headers related to getifaddrs() for `-m auto` on different platforms */
+#ifdef HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#endif
+#include <sys/types.h>
+#ifndef WIN32
+# include <arpa/inet.h>
+# include <netinet/in.h>
+# ifdef HAVE_IFADDRS_H
+#  include <ifaddrs.h>
+# endif
+# include <netdb.h>
+# include <sys/ioctl.h>
+# include <net/if.h>
+#else
+# if defined HAVE_WINSOCK2_H && HAVE_WINSOCK2_H
+#  include <winsock2.h>
+# endif
+# if defined HAVE_IPHLPAPI_H && HAVE_IPHLPAPI_H
+#  include <iphlpapi.h>
+# endif
+# include <ws2tcpip.h>
+# include <wspiapi.h>
+# ifndef AI_NUMERICSERV
+#  define AI_NUMERICSERV NI_NUMERICSERV
+# endif
+# include "wincompat.h"
+#endif
+
+#include "nut_stdint.h"
+
 #ifdef HAVE_PTHREAD
 # include <pthread.h>
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 #  include <semaphore.h>
 # endif
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
-#  include "nut_stdint.h"
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 #  ifdef HAVE_SYS_RESOURCE_H
 #   include <sys/resource.h> /* for getrlimit() and struct rlimit */
 #   include <errno.h>
@@ -49,16 +80,16 @@
  * following practical investigation summarized at
  *   https://github.com/networkupstools/nut/pull/1158
  * and probably means the usual stdin/stdout/stderr triplet
+ * Another +1 is for NetSNMP which wants to open MIB files,
+ * potential per-host configuration files, etc.
  */
-#   define RESERVE_FD_COUNT 3
+#   define RESERVE_FD_COUNT 4
 #  endif /* HAVE_SYS_RESOURCE_H */
-# endif  /* HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE */
+# endif  /* HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 
 #include "nut-scan.h"
 
-#define DEFAULT_TIMEOUT 5
-
 #define ERR_BAD_OPTION	(-1)
 
 static const char optstring[] = "?ht:T:s:e:E:c:l:u:W:X:w:x:p:b:B:d:L:CUSMOAm:QnNPqIVaD";
@@ -87,8 +118,8 @@ static const struct option longopts[] = {
 	{ "usb_scan", no_argument, NULL, 'U' },
 	{ "snmp_scan", no_argument, NULL, 'S' },
 	{ "xml_scan", no_argument, NULL, 'M' },
-	{ "oldnut_scan", no_argument, NULL, 'O' },
-	{ "avahi_scan", no_argument, NULL, 'A' },
+	{ "oldnut_scan", no_argument, NULL, 'O' },	/* "old" NUT libupsclient.so scan */
+	{ "avahi_scan", no_argument, NULL, 'A' },	/* "new" NUT scan where deployed */
 	{ "nut_simulation_scan", no_argument, NULL, 'n' },
 	{ "ipmi_scan", no_argument, NULL, 'I' },
 	{ "disp_nut_conf_with_sanity_check", no_argument, NULL, 'Q' },
@@ -108,12 +139,13 @@ static const struct option longopts[] = {
 static nutscan_device_t *dev[TYPE_END];
 
 static useconds_t timeout = DEFAULT_NETWORK_TIMEOUT * 1000 * 1000; /* in usec */
-static char * start_ip = NULL;
-static char * end_ip = NULL;
 static char * port = NULL;
 static char * serial_ports = NULL;
 static int cli_link_detail_level = -1;
 
+/* Track requested IP ranges (from CLI or auto-discovery) */
+static nutscan_ip_range_list_t ip_ranges_list;
+
 #ifdef HAVE_PTHREAD
 static pthread_t thread[TYPE_END];
 
@@ -170,12 +202,18 @@ static void * run_usb(void *arg)
 	dev[TYPE_USB] = nutscan_scan_usb(scanopts_ptr);
 	return NULL;
 }
+#endif	/* HAVE_PTHREAD */
 
 static void * run_snmp(void * arg)
 {
 	nutscan_snmp_t * sec = (nutscan_snmp_t *)arg;
 
-	dev[TYPE_SNMP] = nutscan_scan_snmp(start_ip, end_ip, timeout, sec);
+	upsdebugx(2, "Entering %s for %" PRIuSIZE " IP address range(s)",
+		__func__, ip_ranges_list.ip_ranges_count);
+
+	dev[TYPE_SNMP] = nutscan_scan_ip_range_snmp(&ip_ranges_list, timeout, sec);
+
+	upsdebugx(2, "Finished %s loop", __func__);
 	return NULL;
 }
 
@@ -183,7 +221,12 @@ static void * run_xml(void * arg)
 {
 	nutscan_xml_t * sec = (nutscan_xml_t *)arg;
 
-	dev[TYPE_XML] = nutscan_scan_xml_http_range(start_ip, end_ip, timeout, sec);
+	upsdebugx(2, "Entering %s for %" PRIuSIZE " IP address range(s)",
+		__func__, ip_ranges_list.ip_ranges_count);
+
+	dev[TYPE_XML] = nutscan_scan_ip_range_xml_http(&ip_ranges_list, timeout, sec);
+
+	upsdebugx(2, "Finished %s loop", __func__);
 	return NULL;
 }
 
@@ -191,7 +234,12 @@ static void * run_nut_old(void *arg)
 {
 	NUT_UNUSED_VARIABLE(arg);
 
-	dev[TYPE_NUT] = nutscan_scan_nut(start_ip, end_ip, port, timeout);
+	upsdebugx(2, "Entering %s for %" PRIuSIZE " IP address range(s)",
+		__func__, ip_ranges_list.ip_ranges_count);
+
+	dev[TYPE_NUT] = nutscan_scan_ip_range_nut(&ip_ranges_list, port, timeout);
+
+	upsdebugx(2, "Finished %s loop", __func__);
 	return NULL;
 }
 
@@ -214,24 +262,717 @@ static void * run_avahi(void *arg)
 static void * run_ipmi(void * arg)
 {
 	nutscan_ipmi_t * sec = (nutscan_ipmi_t *)arg;
+	
+	upsdebugx(2, "Entering %s for %" PRIuSIZE " IP address range(s)",
+		__func__, ip_ranges_list.ip_ranges_count);
+
+	dev[TYPE_IPMI] = nutscan_scan_ip_range_ipmi(&ip_ranges_list, sec);
 
-	dev[TYPE_IPMI] = nutscan_scan_ipmi(start_ip, end_ip, sec);
+	upsdebugx(2, "Finished %s loop", __func__);
 	return NULL;
 }
 
 static void * run_eaton_serial(void *arg)
 {
-	NUT_UNUSED_VARIABLE(arg);
+	char * arg_serial_ports = (char *)arg;
 
-	dev[TYPE_EATON_SERIAL] = nutscan_scan_eaton_serial(serial_ports);
+	dev[TYPE_EATON_SERIAL] = nutscan_scan_eaton_serial(arg_serial_ports);
 	return NULL;
 }
-#endif /* HAVE_PTHREAD */
 
-static void show_usage(void)
+static void handle_arg_cidr(const char *arg_addr, int *auto_nets_ptr)
+{
+	char	*start_ip = NULL, *end_ip = NULL;
+	/* Scanning mode: IPv4, IPv6 or both */
+	int	auto_nets = -1;
+	/* Bit-length limit for *address part* of subnets to consider;
+	 * e.g. if your LAN's network range is 10.2.3.0/24 the address
+	 * part is (32-24)=8. Larger subnets e.g. 10.0.0.0/8 would be
+	 * ignored to avoid billions of scan requests. Note that while
+	 * this is applied to IPv6 also, their typical /64 subnets are
+	 * not likely to have a NUT/SNMP/NetXML/... server *that* close
+	 * nearby in addressing terms, for a tight filter to find them.
+	 */
+	long	masklen_hosts_limit = 8;
+	char	*s = NULL;
+	int	errno_saved;
+	size_t	auto_subnets_found = 0;
+
+#ifdef HAVE_GETIFADDRS
+	/* NOTE: this ifdef is more precise than ifdef WIN32; assuming
+	 * its implementation of getifaddrs() would actually be functional
+	 * if it appears in the OS or mingw/cygwin/... shims eventually.
+	 * If it would be *not* functional, may have to revert to checking
+	 * (also?) for WIN32 here and below. */
+	/* Inspired by https://stackoverflow.com/a/63789267/4715872 */
+	struct ifaddrs	*ifap = NULL, *ifa = NULL;
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+	/* TODO: The two WIN32 approaches overlap quite a bit, deduplicate!
+	 * First shot comes straight from examples as a starting point, but... */
+	/* For Windows newer than Vista. Here and below, inspired by
+	 * https://learn.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getadaptersaddresses
+	 * https://stackoverflow.com/questions/122208/how-can-i-get-the-ip-address-of-a-local-computer
+	 * https://stackoverflow.com/questions/41139561/find-ip-address-of-the-machine-in-c/41151132#41151132
+	 */
+
+#	define WIN32_GAA_WORKING_BUFFER_SIZE	15000
+#	define WIN32_GAA_MAX_TRIES	3
+
+	DWORD	dwRetVal = 0;
+
+	/* Set the flags to pass to GetAdaptersAddresses */
+	ULONG	flags = GAA_FLAG_INCLUDE_PREFIX;
+
+	/* default to unspecified address family (both IPv4 and IPv6) */
+	ULONG	family = AF_UNSPEC;
+
+	PIP_ADAPTER_ADDRESSES		pAddresses = NULL;
+	ULONG	outBufLen = 0;
+	ULONG	Iterations = 0;
+
+	PIP_ADAPTER_ADDRESSES		pCurrAddresses = NULL;
+	PIP_ADAPTER_UNICAST_ADDRESS	pUnicast = NULL;
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+	/* For Windows older than XP (present but not recommended
+	 * in later releases). Here and below, inspired by
+	 * https://learn.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getadaptersinfo
+	 */
+
+	PIP_ADAPTER_INFO	pAdapterInfo;
+	PIP_ADAPTER_INFO	pAdapter = NULL;
+	DWORD	dwRetVal = 0;
+
+	ULONG	ulOutBufLen = sizeof (IP_ADAPTER_INFO);
+#endif
+
+	upsdebugx(3, "Entering %s('%s')", __func__, arg_addr);
+
+#if defined HAVE_GETIFADDRS || (defined WIN32 && (defined HAVE_GETADAPTERSINFO || defined HAVE_GETADAPTERSADDRESSES))
+	/* Is this a `-m auto<something_optional>` mode? */
+	if (!strncmp(arg_addr, "auto", 4)) {
+		/* TODO: Maybe split later, to allow separate
+		 *  `-m auto4/X` and `-m auto6/Y` requests?
+		 */
+		if (auto_nets_ptr && *auto_nets_ptr) {
+			upsdebugx(0, "Duplicate request for connected subnet scan ignored");
+			return;
+		}
+
+		/* Not very efficient to stack strcmp's, but
+		 * also not a hot codepath to care much, either.
+		 */
+		if (!strcmp(arg_addr, "auto")) {
+			auto_nets = 46;
+		} else if (!strcmp(arg_addr, "auto4")) {
+			auto_nets = 4;
+		} else if (!strcmp(arg_addr, "auto6")) {
+			auto_nets = 6;
+		} else if (!strncmp(arg_addr, "auto/", 5)) {
+			auto_nets = 46;
+			errno = 0;
+			masklen_hosts_limit = strtol(arg_addr + 5, &s, 10);
+			errno_saved = errno;
+			upsdebugx(6, "errno=%d s='%s'(%p) input='%s'(%p) output=%ld",
+				errno_saved, NUT_STRARG(s), (void *)s,
+				arg_addr + 5, (void *)(arg_addr + 5),
+				masklen_hosts_limit);
+			if (errno_saved || (s && *s != '\0') || masklen_hosts_limit < 0 || masklen_hosts_limit > 128) {
+				fatalx(EXIT_FAILURE,
+					"Invalid auto-net limit value, should be an integer [0..128]: %s",
+					arg_addr);
+			}
+		} else if (!strncmp(arg_addr, "auto4/", 6)) {
+			auto_nets = 4;
+			errno = 0;
+			masklen_hosts_limit = strtol(arg_addr + 6, &s, 10);
+			errno_saved = errno;
+			upsdebugx(6, "errno=%d s='%s'(%p) input='%s'(%p) output=%ld",
+				errno_saved, NUT_STRARG(s), (void *)s,
+				arg_addr + 6, (void *)(arg_addr + 6),
+				masklen_hosts_limit);
+			if (errno_saved || (s && *s != '\0') || masklen_hosts_limit < 0 || masklen_hosts_limit > 32) {
+				fatalx(EXIT_FAILURE,
+					"Invalid auto-net limit value, should be an integer [0..32]: %s",
+					arg_addr);
+			}
+		} else if (!strncmp(arg_addr, "auto6/", 6)) {
+			auto_nets = 6;
+			errno = 0;
+			masklen_hosts_limit = strtol(arg_addr + 6, &s, 10);
+			errno_saved = errno;
+			upsdebugx(6, "errno=%d s='%s'(%p) input='%s'(%p) output=%ld",
+				errno_saved, NUT_STRARG(s), (void *)s,
+				arg_addr + 6, (void *)(arg_addr + 6),
+				masklen_hosts_limit);
+			if (errno_saved || (s && *s != '\0') || masklen_hosts_limit < 0 || masklen_hosts_limit > 128) {
+				fatalx(EXIT_FAILURE,
+					"Invalid auto-net limit value, should be an integer [0..128]: %s",
+					arg_addr);
+			}
+		} else {
+			/* TODO: maybe fail right away?
+			 *  Or claim a simple auto46 mode? */
+			upsdebugx(0,
+				"Got a '-m auto*' CLI option with unsupported "
+				"keyword pattern; assuming a CIDR, "
+				"likely to fail: %s", arg_addr);
+		}
+
+		/* Let the caller know, to allow for run-once support */
+		if (auto_nets_ptr) {
+			*auto_nets_ptr = auto_nets;
+		}
+	}
+#endif	/* HAVE_GETIFADDRS || HAVE_GETADAPTERSINFO || HAVE_GETADAPTERSADDRESSES */
+
+	if (auto_nets < 0) {
+		/* not a supported `-m auto*` pattern => is `-m cidr` */
+		upsdebugx(5, "Processing CIDR net/mask: %s", arg_addr);
+		nutscan_cidr_to_ip(arg_addr, &start_ip, &end_ip);
+		upsdebugx(5, "Extracted IP address range from CIDR net/mask: %s => %s", start_ip, end_ip);
+
+		nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+		start_ip = NULL;
+		end_ip = NULL;
+		return;
+	}
+
+#if defined HAVE_GETIFADDRS || (defined WIN32 && (defined HAVE_GETADAPTERSINFO || defined HAVE_GETADAPTERSADDRESSES))
+	/* Handle `-m auto*` modes below */
+#ifdef HAVE_GETIFADDRS
+	upsdebugx(4, "%s: using getifaddrs()", __func__);
+
+	if (getifaddrs(&ifap) < 0 || !ifap) {
+		if (ifap)
+			freeifaddrs(ifap);
+		fatal_with_errno(EXIT_FAILURE,
+			"Failed to getifaddrs() for connected subnet scan");
+		/* TOTHINK: Non-fatal, just return / goto finish?
+		 * Either way, do not proceed with code below! */
+	}
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+	upsdebugx(4, "%s: using GetAdaptersAddresses()", __func__);
+
+	switch (auto_nets) {
+	case 4:
+		family = AF_INET;
+		break;
+
+	case 6:
+		family = AF_INET6;
+		break;
+
+	case 46:
+	default:
+		family = AF_UNSPEC;
+		break;
+	}
+
+	/* Allocate a 15 KB buffer to start with; we will be told
+	 * if more is needed (hence the loop below) */
+	outBufLen = WIN32_GAA_WORKING_BUFFER_SIZE;
+
+	do {
+		pAddresses = (IP_ADAPTER_ADDRESSES *) xcalloc(1, outBufLen);
+
+		dwRetVal =
+		    GetAdaptersAddresses(family, flags, NULL, pAddresses, &outBufLen);
+
+		if (dwRetVal == ERROR_BUFFER_OVERFLOW) {
+		    free(pAddresses);
+		    pAddresses = NULL;
+		} else {
+		    break;
+		}
+
+		Iterations++;
+	} while (
+		(dwRetVal == ERROR_BUFFER_OVERFLOW)
+		&& (Iterations < WIN32_GAA_MAX_TRIES)
+		);
+
+	if (dwRetVal != NO_ERROR) {
+		char	msgPrefix[LARGEBUF];
+
+		snprintf(msgPrefix, sizeof(msgPrefix),
+			"Failed to GetAdaptersAddresses() for "
+			"connected subnet scan (%" PRIiMAX ")",
+			(intmax_t)dwRetVal);
+
+		if (pAddresses) {
+			free(pAddresses);
+			pAddresses = NULL;
+		}
+
+		if (dwRetVal == ERROR_NO_DATA) {
+			fatalx(EXIT_FAILURE, "%s: %s",
+				msgPrefix,
+				"No addresses were found for the requested parameters");
+		} else {
+			LPVOID	lpMsgBuf = NULL;
+
+			if (FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
+				FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS, 
+				NULL, dwRetVal, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),   
+				// Default language
+				(LPTSTR) & lpMsgBuf, 0, NULL) && lpMsgBuf
+			) {
+				fatalx(EXIT_FAILURE, "%s: %s",
+					msgPrefix,
+					(LPTSTR)lpMsgBuf);
+			}
+
+			if (lpMsgBuf)
+				LocalFree(lpMsgBuf);
+			fatalx(EXIT_FAILURE, "%s", msgPrefix);
+		}
+
+		/* TOTHINK: Non-fatal, just return / goto finish?
+		 * Either way, do not proceed with code below! */
+	}
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+	upsdebugx(4, "%s: using GetAdaptersInfo()", __func__);
+
+	/* NOTE: IPv4 only! */
+	if (auto_nets == 6) {
+		fatalx(EXIT_FAILURE,
+			"Requested explicitly to query only IPv6 addresses, "
+			"but current system libraries support only IPv4."
+			);
+
+		/* TOTHINK: Non-fatal, just return / goto finish?
+		 * Either way, do not proceed with code below! */
+	}
+
+	pAdapterInfo = (IP_ADAPTER_INFO *) xcalloc(1, sizeof (IP_ADAPTER_INFO));
+
+	/* Make an initial call to GetAdaptersInfo to get
+	 * the necessary size into the ulOutBufLen variable */
+	if (GetAdaptersInfo(pAdapterInfo, &ulOutBufLen) == ERROR_BUFFER_OVERFLOW) {
+		free(pAdapterInfo);
+		pAdapterInfo = (IP_ADAPTER_INFO *) xcalloc(1, ulOutBufLen);
+	}
+
+	if ((dwRetVal = GetAdaptersInfo(pAdapterInfo, &ulOutBufLen)) != NO_ERROR) {
+		if (pAdapterInfo) {
+			free(pAdapterInfo);
+			pAdapterInfo = NULL;
+		}
+
+		fatalx(EXIT_FAILURE,
+			"Failed to GetAdaptersAddresses() for "
+			"connected subnet scan (%" PRIiMAX ")",
+			(intmax_t)dwRetVal);
+
+		/* TOTHINK: Non-fatal, just return / goto finish?
+		 * Either way, do not proceed with code below! */
+	}
+#else
+	fatalx(EXIT_FAILURE,
+		"Have no way to query local interface addresses on this "
+		"platform, please run without the '-m auto*' options!");
+#endif
+
+	/* Initial query did not fail, start a new scope
+	 * for more variables, to be allocated just now */
+	{
+		char	msg[LARGEBUF];
+		char	cidr[LARGEBUF];
+		/* Note: INET6_ADDRSTRLEN is large enough for IPv4 too,
+		 * and is smaller than LARGEBUF to avoid snprintf()
+		 * warnings that the result might not fit. */
+		char	addr[INET6_ADDRSTRLEN];
+		char	mask[INET6_ADDRSTRLEN];
+		int	masklen_subnet = 0;
+		int	masklen_hosts = 0;
+		uintmax_t	ifflags = 0, iftype = 0;
+
+#ifdef HAVE_GETIFADDRS
+		/* Every IP address (even if aliases on same interfaces)
+		 * has its own "ifa" value.
+		 */
+		for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
+			const char	*ifname = ifa->ifa_name;
+
+			ifflags = (uintmax_t)ifa->ifa_flags;
+			iftype  = ifflags;
+
+			if (ifa->ifa_addr)
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+		/* Nested structure can hold many addresses of different
+		 * families assigned to the same physical interface.
+		 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_adapter_addresses_lh
+		 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_adapter_unicast_address_lh
+		 */
+		for (pCurrAddresses = pAddresses; pCurrAddresses; pCurrAddresses = pCurrAddresses->Next) {
+			char	ifname[LARGEBUF];
+			size_t	ifnamelen = 0;
+
+			ifflags = (uintmax_t)pCurrAddresses->Flags;
+			iftype  = (uintmax_t)pCurrAddresses->IfType;
+
+			/* Convert some fields from wide chars */
+			ifnamelen += snprintf(
+				ifname, 
+				sizeof(ifname),
+				"%s (",
+				pCurrAddresses->AdapterName);
+			ifnamelen += wcstombs(
+				ifname + ifnamelen,
+				pCurrAddresses->FriendlyName,
+				sizeof(ifname) - ifnamelen);
+			ifnamelen += snprintf(
+				ifname + ifnamelen,
+				sizeof(ifname) - ifnamelen,
+				"): ");
+			ifnamelen += wcstombs(
+				ifname + ifnamelen,
+				pCurrAddresses->Description,
+				sizeof(ifname) - ifnamelen);
+
+			if ( (ifflags & IP_ADAPTER_IPV6_ENABLED)
+			||   (ifflags & IP_ADAPTER_IPV4_ENABLED)
+			) for (pUnicast = pCurrAddresses->FirstUnicastAddress; pUnicast; pUnicast = pUnicast->Next)
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+		/* NOTE: IPv4 only!
+		 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_adapter_info
+		 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_addr_string
+		 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_address_string
+		 */
+		for (pAdapter = pAdapterInfo; pAdapter; pAdapter = pAdapter->Next) {
+			IP_ADDR_STRING	*pUnicast;
+			char	ifname[LARGEBUF];
+			size_t	ifnamelen = 0;
+
+			iftype  = (uintmax_t)pAdapter->Type;
+			ifflags = iftype; /* The nearest they have to flags */
+			ifnamelen += snprintf(
+				ifname,
+				sizeof(ifname),
+				"%s: %s",
+				pAdapter->AdapterName,
+				pAdapter->Description);
+
+			for (pUnicast = &(pAdapter->IpAddressList); pUnicast; pUnicast = pUnicast->Next)
+#endif
+			{	/* Have some address to handle */
+				memset(msg, 0, sizeof(msg));
+				memset(addr, 0, sizeof(addr));
+				memset(mask, 0, sizeof(mask));
+				masklen_subnet = -1;
+
+#if defined HAVE_GETIFADDRS || (defined WIN32 && defined HAVE_GETADAPTERSADDRESSES)
+# ifdef HAVE_GETIFADDRS
+				if (ifa->ifa_addr->sa_family == AF_INET6)
+# elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+				if (pUnicast->Address.lpSockaddr->sa_family == AF_INET6)
+# elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+				if (0)	/* No IPv6 for this library call */
+# endif
+				{	/* IPv6 */
+# ifdef HAVE_GETIFADDRS
+					uint8_t	i, j;
+
+					/* Ensure proper alignment */
+					struct sockaddr_in6 sa, sm;
+					memcpy (&sa, ifa->ifa_addr, sizeof(struct sockaddr_in6));
+					memcpy (&sm, ifa->ifa_netmask, sizeof(struct sockaddr_in6));
+
+					/* FIXME: Here and below, this code
+					 * technically just counts set bits
+					 * and we assume they are a single
+					 * contiguous range in the address
+					 * portion of the IP address for a
+					 * netmask.
+					 */
+					masklen_subnet = 0;
+					for (j = 0; j < 16; j++) {
+						i = sm.sin6_addr.s6_addr[j];
+						while (i) {
+							masklen_subnet += i & 1;
+							i >>= 1;
+						}
+					}
+# elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					/* This structure member is only available on Windows Vista and later.
+					 * If we need earlier versions built for, need to use common struct.
+					 * https://learn.microsoft.com/en-us/windows/win32/api/iptypes/ns-iptypes-ip_adapter_unicast_address_lh
+					 */
+					masklen_subnet = pUnicast->OnLinkPrefixLength;
+# elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+					masklen_subnet = 128;	/* no-op anyway */
+# endif
+					masklen_hosts = 128 - masklen_subnet;
+
+# ifdef HAVE_GETIFADDRS
+					getnameinfo((struct sockaddr *)&sa, sizeof(struct sockaddr_in6), addr, sizeof(addr), NULL, 0, NI_NUMERICHOST);
+					getnameinfo((struct sockaddr *)&sm, sizeof(struct sockaddr_in6), mask, sizeof(mask), NULL, 0, NI_NUMERICHOST);
+# elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					getnameinfo(pUnicast->Address.lpSockaddr, sizeof(struct sockaddr_in6), addr, sizeof(addr), NULL, 0, NI_NUMERICHOST);
+					/* We have no real need for mask as an IP
+					 * string except debug logs, so let it be */
+					snprintf(mask, sizeof(mask), "/%i", masklen_subnet);
+# elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+# endif
+
+					snprintf(msg, sizeof(msg),
+						"Interface: %s\tAddress: %s\tMask: %s (subnet: %i, hosts: %i)\tFlags: %08" PRIxMAX "\tType: %08" PRIxMAX,
+						ifname, addr, mask,
+						masklen_subnet, masklen_hosts,
+						ifflags, iftype);
+				}	/* IPv6 */
+#endif	/* HAVE_GETIFADDRS || HAVE_GETADAPTERSADDRESSES */
+				
+#ifdef HAVE_GETIFADDRS
+				else
+				if (ifa->ifa_addr->sa_family == AF_INET)
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+				else
+				if (pUnicast->Address.lpSockaddr->sa_family == AF_INET)
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+				/* NOTE: No "else", no "if": IPv6 was skipped
+				 * on this platform and IPv4 was the only option */
+#endif
+				{	/* IPv4 */
+#ifdef HAVE_GETIFADDRS
+					in_addr_t	i;
+
+					/* Ensure proper alignment */
+					struct sockaddr_in sa, sm;
+					memcpy (&sa, ifa->ifa_addr, sizeof(struct sockaddr_in));
+					memcpy (&sm, ifa->ifa_netmask, sizeof(struct sockaddr_in));
+
+					snprintf(addr, sizeof(addr), "%s", inet_ntoa(sa.sin_addr));
+					snprintf(mask, sizeof(mask), "%s", inet_ntoa(sm.sin_addr));
+
+					i = sm.sin_addr.s_addr;
+					masklen_subnet = 0;
+					while (i) {
+						masklen_subnet += i & 1;
+						i >>= 1;
+					}
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					masklen_subnet = pUnicast->OnLinkPrefixLength;
+
+					getnameinfo(pUnicast->Address.lpSockaddr, sizeof(struct sockaddr_in), addr, sizeof(addr), NULL, 0, NI_NUMERICHOST);
+					/* We have no real need for mask as an IP
+					 * string except debug logs, so let it be */
+					snprintf(mask, sizeof(mask), "/%i", masklen_subnet);
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+					struct sockaddr_in	sm;
+
+					snprintf(addr, sizeof(addr) > 16 ? 16 : sizeof(addr), "%s", pUnicast->IpAddress.String);
+					snprintf(mask, sizeof(mask) > 16 ? 16 : sizeof(mask), "%s", pUnicast->IpMask.String);
+
+					masklen_subnet = 0;
+					if (inet_pton(AF_INET, mask, &sm.sin_addr)) {
+						uint32_t	i = sm.sin_addr.s_addr;
+						while (i) {
+							masklen_subnet += i & 1;
+							i >>= 1;
+						}
+					}
+#endif
+					masklen_hosts = 32 - masklen_subnet;
+
+					snprintf(msg, sizeof(msg),
+						"Interface: %s\tAddress: %s\tMask: %s (subnet: %i, hosts: %i)\tFlags: %08" PRIxMAX "\tType: %08" PRIxMAX,
+						ifname, addr, mask,
+						masklen_subnet, masklen_hosts,
+						ifflags, iftype);
+				}	/* IPv4 */
+
+#ifdef HAVE_GETIFADDRS
+/*
+				else {
+					snprintf(msg, sizeof(msg), "Addr family: %" PRIuMAX, (intmax_t)ifa->ifa_addr->sa_family);
+				}
+*/
+#endif
+
+#ifdef HAVE_GETIFADDRS
+				if (ifa->ifa_addr->sa_family == AF_INET6 || ifa->ifa_addr->sa_family == AF_INET) {
+					if (iftype & IFF_LOOPBACK)
+						snprintfcat(msg, sizeof(msg), " IFF_LOOPBACK");
+					if (iftype & IFF_UP)
+						snprintfcat(msg, sizeof(msg), " IFF_UP");
+					if (iftype & IFF_RUNNING)
+						snprintfcat(msg, sizeof(msg), " IFF_RUNNING");
+					if (iftype & IFF_BROADCAST)
+						snprintfcat(msg, sizeof(msg), " IFF_BROADCAST(is assigned)");
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+				/* https://learn.microsoft.com/en-us/windows/win32/api/nldef/ne-nldef-nl_prefix_origin
+				 * https://learn.microsoft.com/en-us/windows/win32/api/nldef/ne-nldef-nl_suffix_origin
+				 */
+				if (pUnicast->Address.lpSockaddr->sa_family == AF_INET
+				||  pUnicast->Address.lpSockaddr->sa_family == AF_INET6
+				) {
+					if (iftype == IF_TYPE_OTHER)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_OTHER");
+					if (iftype == IF_TYPE_ETHERNET_CSMACD)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_ETHERNET_CSMACD");
+					if (iftype == IF_TYPE_ISO88025_TOKENRING)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_ISO88025_TOKENRING");
+					if (iftype == IF_TYPE_PPP)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_PPP");
+					if (iftype == IF_TYPE_SOFTWARE_LOOPBACK)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_SOFTWARE_LOOPBACK");
+					if (iftype == IF_TYPE_ATM)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_ATM");
+					if (iftype == IF_TYPE_IEEE80211)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_IEEE80211");
+					if (iftype == IF_TYPE_TUNNEL)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_TUNNEL");
+					if (iftype == IF_TYPE_IEEE1394)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_IEEE1394");
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+				{	/* Just scoping for this platform */
+					if (iftype == MIB_IF_TYPE_OTHER)
+						snprintfcat(msg, sizeof(msg), " MIB_IF_TYPE_OTHER");
+					if (iftype == MIB_IF_TYPE_ETHERNET)
+						snprintfcat(msg, sizeof(msg), " MIB_IF_TYPE_ETHERNET");
+					if (iftype == IF_TYPE_ISO88025_TOKENRING)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_ISO88025_TOKENRING");
+					if (iftype == MIB_IF_TYPE_PPP)
+						snprintfcat(msg, sizeof(msg), " MIB_IF_TYPE_PPP");
+					if (iftype == MIB_IF_TYPE_LOOPBACK)
+						snprintfcat(msg, sizeof(msg), " MIB_IF_TYPE_LOOPBACK");
+					if (iftype == MIB_IF_TYPE_SLIP)
+						snprintfcat(msg, sizeof(msg), " MIB_IF_TYPE_SLIP");
+					if (iftype == IF_TYPE_IEEE80211)
+						snprintfcat(msg, sizeof(msg), " IF_TYPE_IEEE80211");
+#endif
+
+					upsdebugx(5, "Discovering getifaddrs(): %s", msg);
+
+#ifdef HAVE_GETIFADDRS
+					if (!(
+						(auto_nets == 46
+					     || (auto_nets == 4 && ifa->ifa_addr->sa_family == AF_INET)
+					     || (auto_nets == 6 && ifa->ifa_addr->sa_family == AF_INET6) )
+					)) {
+						upsdebugx(6, "Subnet ignored: not of the requested address family");
+						continue;
+					}
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					if (!(
+						(auto_nets == 46
+					     || (auto_nets == 4 && pUnicast->Address.lpSockaddr->sa_family == AF_INET)
+					     || (auto_nets == 6 && pUnicast->Address.lpSockaddr->sa_family == AF_INET6) )
+					)) {
+						upsdebugx(6, "Subnet ignored: not of the requested address family");
+						continue;
+					}
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+#endif
+
+					if (
+						!strcmp(addr, "0.0.0.0")
+						|| !strcmp(addr, "*")
+						|| !strcmp(addr, "::")
+						|| !strcmp(addr, "0::")
+					) {
+						/* FIXME: IPv6 spellings? Search for hex/digits other than 0? */
+						upsdebugx(6, "Subnet ignored: host address not assigned or mis-detected");
+						continue;
+					}
+
+					if (masklen_hosts_limit < masklen_hosts) {
+						/* NOTE: masklen_hosts==0 means
+						 * an exact hit on one address,
+						 * so an IPv4/32 or IPv6/128.
+						 */
+						upsdebugx(6, "Subnet ignored: address range too large: %ld bits allowed vs. %d bits per netmask",
+							masklen_hosts_limit, masklen_hosts);
+						continue;
+					}
+
+#ifdef HAVE_GETIFADDRS
+					if (iftype & IFF_LOOPBACK)
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					if (iftype == IF_TYPE_SOFTWARE_LOOPBACK)
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+					if (iftype == MIB_IF_TYPE_LOOPBACK)
+#endif
+					{
+						upsdebugx(6, "Subnet ignored: loopback");
+						continue;
+					}
+					/* TODO? Filter other interface types? */
+
+#ifdef HAVE_GETIFADDRS
+					if (!(
+						(ifflags & IFF_UP)
+					   &&   (ifflags & IFF_RUNNING)
+					   &&   (ifflags & IFF_BROADCAST)
+					)) {
+						upsdebugx(6, "Subnet ignored: not up and running, with a proper broadcast-able address");
+						continue;
+					}
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+					if (pCurrAddresses->OperStatus != IfOperStatusUp) {
+						upsdebugx(6, "Subnet ignored: not up and running");
+						continue;
+					}
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+#endif
+
+					/* TODO: also rule out "link-local" address ranges
+					 * so we do not issue billions of worthless scans.
+					 * FIXME: IPv6 may also be a problem, see
+					 * https://github.com/networkupstools/nut/issues/2512
+					 */
+					if (snprintf(cidr, sizeof(cidr), "%s/%i", addr, masklen_subnet) < 0) {
+						fatalx(EXIT_FAILURE, "Could not construct a CIDR string from discovered address/mask");
+					}
+
+					upsdebugx(5, "Processing CIDR net/mask: %s", cidr);
+					nutscan_cidr_to_ip(cidr, &start_ip, &end_ip);
+					upsdebugx(5, "Extracted IP address range from CIDR net/mask: %s => %s", start_ip, end_ip);
+
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+
+					auto_subnets_found++;
+				}	/* else AF_UNIX or a dozen other types we do not care about here */
+			}
+		}
+	}
+
+/*finish:*/
+#ifdef HAVE_GETIFADDRS
+	if (ifap) {
+		freeifaddrs(ifap);
+	}
+#elif defined WIN32 && defined HAVE_GETADAPTERSADDRESSES
+	if (pAddresses) {
+		free(pAddresses);
+	}
+#elif defined WIN32 && defined HAVE_GETADAPTERSINFO
+	if (pAdapterInfo) {
+		free(pAdapterInfo);
+	}
+#endif
+
+	if (!auto_subnets_found) {
+		upsdebugx(0, "WARNING: A '-m auto*' request selected no subnets!\n"
+			"Please check for reasons with higher debug verbosity (up to 6).");
+	}
+	upsdebugx(3, "Finished %s('%s'), selected %" PRIuSIZE " subnets automatically",
+		__func__, arg_addr, auto_subnets_found);
+#else	/* not (HAVE_GETIFADDRS || ( WIN32 && (HAVE_GETADAPTERSINFO || HAVE_GETADAPTERSADDRESSES))) */
+	fatalx(EXIT_FAILURE,
+		"Have no way to query local interface addresses on this "
+		"platform, please run without the '-m auto*' options!");
+#endif	/* HAVE_GETIFADDRS || ( WIN32 && (HAVE_GETADAPTERSINFO || HAVE_GETADAPTERSADDRESSES)) */
+}
+
+static void show_usage(const char *arg_progname)
 {
 /* NOTE: This code uses `nutscan_avail_*` global vars from nutscan-init.c */
-	puts("nut-scanner : utility for detection of available power devices.\n");
+	print_banner_once(arg_progname, 2);
+	puts("NUT utility for detection of available power devices.\n");
 
 	nut_report_config_flags();
 
@@ -239,7 +980,8 @@ static void show_usage(void)
 	printf("  -C, --complete_scan: Scan all available devices except serial ports (default).\n");
 	if (nutscan_avail_usb) {
 		printf("  -U, --usb_scan: Scan USB devices. Specify twice or more to report different\n"
-			"                  detail levels of (change-prone) physical properties.\n");
+			"                  detail levels of (change-prone) physical properties.\n"
+			"                  This usage can be combined with '-C' or other scan types.\n");
 	} else {
 		printf("* Options for USB devices scan not enabled: library not detected.\n");
 	}
@@ -253,11 +995,11 @@ static void show_usage(void)
 	} else {
 		printf("* Options for XML/HTTP devices scan not enabled: library not detected.\n");
 	}
-	printf("  -O, --oldnut_scan: Scan NUT devices (old method).\n");
+	printf("  -O, --oldnut_scan: Scan NUT devices (old method via libupsclient).\n");
 	if (nutscan_avail_avahi) {
-		printf("  -A, --avahi_scan: Scan NUT devices (avahi method).\n");
+		printf("  -A, --avahi_scan: Scan NUT devices (new avahi method).\n");
 	} else {
-		printf("* Options for NUT devices (avahi method) scan not enabled: library not detected.\n");
+		printf("* Options for NUT devices (new avahi method) scan not enabled: library not detected.\n");
 	}
 	printf("  -n, --nut_simulation_scan: Scan for NUT simulated devices (.dev files in $CONFPATH).\n");
 	if (nutscan_avail_ipmi) {
@@ -268,7 +1010,7 @@ static void show_usage(void)
 
 	printf("  -E, --eaton_serial <serial ports list>: Scan serial Eaton devices (XCP, SHUT and Q1).\n");
 
-#if (defined HAVE_PTHREAD) && (defined HAVE_PTHREAD_TRYJOIN)
+#if (defined HAVE_PTHREAD) && ( (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED) )
 	printf("  -T, --thread <max number of threads>: Limit the amount of scanning threads running simultaneously (default: %" PRIuSIZE ").\n", max_threads);
 #else
 	printf("  -T, --thread <max number of threads>: Limit the amount of scanning threads running simultaneously (not implemented in this build: no pthread support)\n");
@@ -283,6 +1025,15 @@ static void show_usage(void)
 	printf("  -s, --start_ip <IP address>: First IP address to scan.\n");
 	printf("  -e, --end_ip <IP address>: Last IP address to scan.\n");
 	printf("  -m, --mask_cidr <IP address/mask>: Give a range of IP using CIDR notation.\n");
+	printf("  -m, --mask_cidr auto: Detect local IP address(es) and scan corresponding subnet(s).\n");
+#if !(defined HAVE_GETIFADDRS || (defined WIN32 && (defined HAVE_GETADAPTERSINFO || defined HAVE_GETADAPTERSADDRESSES)))
+	printf("                        (Currently not implemented for this platform)\n");
+#endif
+	printf("  -m, --mask_cidr auto4/auto6: Likewise, limiting to IPv4 or IPv6 interfaces.\n");
+	printf("                        Only the first auto* request would be honoured.\n");
+	printf("NOTE: IP address range specifications can be repeated, to scan several.\n");
+	printf("Specifying a single first or last address before starting another range\n");
+	printf("leads to scanning just that one address as the range.\n");
 
 	if (nutscan_avail_snmp) {
 		printf("\nSNMP v1 specific options:\n");
@@ -407,11 +1158,13 @@ static void show_usage(void)
 
 int main(int argc, char *argv[])
 {
+	const char	*progname = xbasename(argv[0]);
 	nutscan_snmp_t snmp_sec;
 	nutscan_ipmi_t ipmi_sec;
 	nutscan_xml_t  xml_sec;
 	int opt_ret;
-	char *	cidr = NULL;
+	char *start_ip = NULL, *end_ip = NULL;
+	int auto_nets = 0;
 	int allow_all = 0;
 	int allow_usb = 0;
 	int allow_snmp = 0;
@@ -425,11 +1178,11 @@ int main(int argc, char *argv[])
 	void (*display_func)(nutscan_device_t * device);
 	int ret_code = EXIT_SUCCESS;
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	sem_t	*current_sem;
 # endif
 #endif
-#if (defined HAVE_PTHREAD) && ( (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE) ) && (defined HAVE_SYS_RESOURCE_H)
+#if (defined HAVE_PTHREAD) && ( (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED) ) && (defined HAVE_SYS_RESOURCE_H)
 	struct rlimit nofile_limit;
 
 	/* Limit the max scanning thread count by the amount of allowed open
@@ -443,7 +1196,7 @@ int main(int argc, char *argv[])
 	/* Get max number of files. */
 	if (getrlimit(RLIMIT_NOFILE, &nofile_limit) != 0) {
 		/* Report error, keep hardcoded default */
-		fprintf(stderr, "getrlimit() failed with errno=%d, keeping default job limits\n", errno);
+		upsdebug_with_errno(0, "getrlimit() failed, keeping default job limits");
 		nofile_limit.rlim_cur = 0;
 		nofile_limit.rlim_max = 0;
 	} else {
@@ -458,7 +1211,7 @@ int main(int argc, char *argv[])
 			}
 		}
 	}
-#endif /* HAVE_PTHREAD && ( HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE ) && HAVE_SYS_RESOURCE_H */
+#endif	/* HAVE_PTHREAD && ( HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED ) && HAVE_SYS_RESOURCE_H */
 
 	memset(&snmp_sec, 0, sizeof(snmp_sec));
 	memset(&ipmi_sec, 0, sizeof(ipmi_sec));
@@ -469,6 +1222,7 @@ int main(int argc, char *argv[])
 	ipmi_sec.ipmi_version = IPMI_1_5; /* default to IPMI 1.5, if not otherwise specified */
 	ipmi_sec.cipher_suite_id = 3; /* default to HMAC-SHA1; HMAC-SHA1-96; AES-CBC-128 */
 	ipmi_sec.privilege_level = IPMI_PRIVILEGE_LEVEL_ADMIN; /* should be sufficient */
+	ipmi_sec.peername = NULL;
 
 	/* Set the default values for XML HTTP (run_xml()) */
 	xml_sec.port_http = 80;
@@ -484,6 +1238,7 @@ int main(int argc, char *argv[])
 			nut_debug_level++;
 	}
 
+	nutscan_init_ip_ranges(&ip_ranges_list);
 	nutscan_init();
 
 	/* Default, see -Q/-N/-P below */
@@ -500,31 +1255,95 @@ int main(int argc, char *argv[])
 
 		switch(opt_ret) {
 			case 't':
-				timeout = (useconds_t)atol(optarg) * 1000 * 1000; /*in usec*/
-				if (timeout <= 0) {
-					fprintf(stderr,
-						"Illegal timeout value, using default %ds\n",
-						DEFAULT_NETWORK_TIMEOUT);
-					timeout = DEFAULT_NETWORK_TIMEOUT * 1000 * 1000;
+				{ // scoping
+					long	l;
+					char	*s = NULL;
+					int	errno_saved;
+
+					errno = 0;
+					l = strtol(optarg, &s, 10);
+					errno_saved = errno;
+					upsdebugx(6, "errno=%d s='%s'(%p) input='%s'(%p) output=%ld",
+						errno_saved, NUT_STRARG(s), (void *)s,
+						optarg, (void *)(optarg), l);
+
+					if (errno_saved || (s && *s != '\0') || l <= 0) {
+						/* TODO: Any max limit? At least,
+						 * max(useconds_t)/1000000 ? */
+						upsdebugx(0,
+							"Illegal timeout value, using default %ds",
+							DEFAULT_NETWORK_TIMEOUT);
+						timeout = DEFAULT_NETWORK_TIMEOUT * 1000 * 1000;
+					} else {
+						timeout = (useconds_t)l * 1000 * 1000; /*in usec*/
+					}
 				}
 				break;
 			case 's':
-				start_ip = strdup(optarg);
-				if (end_ip == NULL)
-					end_ip = start_ip;
+				if (start_ip) {
+					/* Save whatever we have, either
+					 * this one address or an earlier
+					 * known range with its end */
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+				}
+
+				if (optarg[0] == '[' && optarg[strlen(optarg) - 1] == ']') {
+					start_ip = strdup(optarg + 1);
+					start_ip[strlen(start_ip) - 1] = '\0';
+				} else {
+					start_ip = strdup(optarg);
+				}
+
+				if (end_ip != NULL) {
+					/* Already we know two addresses, save them */
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+				}
 				break;
 			case 'e':
-				end_ip = strdup(optarg);
-				if (start_ip == NULL)
-					start_ip = end_ip;
+				if (end_ip) {
+					/* Save whatever we have, either
+					 * this one address or an earlier
+					 * known range with its start */
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+				}
+
+				if (optarg[0] == '[' && optarg[strlen(optarg) - 1] == ']') {
+					end_ip = strdup(optarg + 1);
+					end_ip[strlen(end_ip) - 1] = '\0';
+				} else {
+					end_ip = strdup(optarg);
+				}
+
+				if (start_ip != NULL) {
+					/* Already we know two addresses, save them */
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+				}
 				break;
 			case 'E':
 				serial_ports = strdup(optarg);
 				allow_eaton_serial = 1;
 				break;
 			case 'm':
-				cidr = strdup(optarg);
-				upsdebugx(5, "Got CIDR net/mask: %s", cidr);
+				if (start_ip || end_ip) {
+					/* Save whatever we have, either
+					 * this one address or an earlier
+					 * known range with its start or end */
+					nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+					start_ip = NULL;
+					end_ip = NULL;
+				}
+
+				/* Large code block offloaded into a method */
+				handle_arg_cidr(optarg, &auto_nets);
+
 				break;
 			case 'D':
 				/* nothing to do, here */
@@ -606,8 +1425,8 @@ int main(int argc, char *argv[])
 					ipmi_sec.authentication_type = IPMI_AUTHENTICATION_TYPE_MD5;
 				}
 				else {
-					fprintf(stderr,
-						"Unknown authentication type (%s). Defaulting to MD5\n",
+					upsdebugx(0,
+						"Unknown authentication type (%s). Defaulting to MD5",
 						optarg);
 				}
 				break;
@@ -623,7 +1442,7 @@ int main(int argc, char *argv[])
 				port = strdup(optarg);
 				break;
 			case 'T': {
-#if (defined HAVE_PTHREAD) && ( (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE) )
+#if (defined HAVE_PTHREAD) && ( (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED) )
 				char* endptr;
 				long val = strtol(optarg, &endptr, 10);
 				/* With endptr we check that no chars were left in optarg
@@ -651,27 +1470,27 @@ int main(int argc, char *argv[])
 							max_threads -= RESERVE_FD_COUNT;
 						}
 
-						fprintf(stderr,
+						upsdebugx(0,
 							"WARNING: Requested max scanning "
 							"thread count %s (%ld) exceeds the "
 							"current file descriptor count limit "
 							"(minus reservation), constraining "
-							"to %" PRIuSIZE "\n",
+							"to %" PRIuSIZE,
 							optarg, val, max_threads);
 					} else
 # endif /* HAVE_SYS_RESOURCE_H */
 						max_threads = (size_t)val;
 				} else {
-					fprintf(stderr,
+					upsdebugx(0,
 						"WARNING: Requested max scanning "
 						"thread count %s (%ld) is out of range, "
-						"using default %" PRIuSIZE "\n",
+						"using default %" PRIuSIZE,
 						optarg, val, max_threads);
 				}
 #else
-				fprintf(stderr,
+				upsdebugx(0,
 					"WARNING: Max scanning thread count option "
-					"is not supported in this build, ignored\n");
+					"is not supported in this build, ignored");
 #endif /* HAVE_PTHREAD && ways to limit the thread count */
 				}
 				break;
@@ -683,7 +1502,8 @@ int main(int argc, char *argv[])
 					goto display_help;
 				}
 				allow_usb = 1;
-				/* NOTE: Starts as -1, so the first -U sets it to 0 (minimal detail) */
+				/* NOTE: Starts as -1, so the first -U sets it to 0
+				 * (minimal detail); further -U can bump it */
 				if (cli_link_detail_level < 3)
 					cli_link_detail_level++;
 				break;
@@ -724,7 +1544,9 @@ int main(int argc, char *argv[])
 				quiet = 1;
 				break;
 			case 'V':
-				printf("Network UPS Tools - %s\n", NUT_VERSION_MACRO);
+				/* just show the version and optional
+				 * CONFIG_FLAGS banner if available */
+				print_banner_once(progname, 1);
 				nut_report_config_flags();
 				exit(EXIT_SUCCESS);
 			case 'a':
@@ -753,7 +1575,7 @@ int main(int argc, char *argv[])
 			case 'h':
 			default:
 display_help:
-				show_usage();
+				show_usage(progname);
 				if ((opt_ret != 'h') || (ret_code != EXIT_SUCCESS))
 					fprintf(stderr, "\n\n"
 						"WARNING: Some error has occurred while processing 'nut-scanner' command-line\n"
@@ -763,12 +1585,40 @@ int main(int argc, char *argv[])
 	}
 
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+	{	/* scoping for the string */
+#  if defined HAVE_SEMAPHORE_UNNAMED
+		char * semsuf = "_UNNAMED";
+#  elif defined HAVE_SEMAPHORE_NAMED
+		char * semsuf = "_NAMED";
+#  else
+		char * semsuf = "*";
+#  endif
+		NUT_UNUSED_VARIABLE(semsuf);	/* just in case */
+
+# if (defined HAVE_PTHREAD_TRYJOIN) && ((defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED))
+		upsdebugx(1, "Parallel scan support: HAVE_PTHREAD && HAVE_PTHREAD_TRYJOIN && HAVE_SEMAPHORE%s", semsuf);
+# elif (defined HAVE_PTHREAD_TRYJOIN)
+		upsdebugx(1, "Parallel scan support: HAVE_PTHREAD && HAVE_PTHREAD_TRYJOIN && !HAVE_SEMAPHORE*");
+# elif (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		upsdebugx(1, "Parallel scan support: HAVE_PTHREAD && !HAVE_PTHREAD_TRYJOIN && HAVE_SEMAPHORE%s", semsuf);
+# else
+		upsdebugx(1, "Parallel scan support: HAVE_PTHREAD && !HAVE_PTHREAD_TRYJOIN && !HAVE_SEMAPHORE*");
+# endif
+	}
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	/* FIXME: Currently sem_init already done on nutscan-init for lib need.
 	   We need to destroy it before re-init. We currently can't change "sem value"
 	   on lib (need to be thread safe). */
 	current_sem = nutscan_semaphore();
+#  ifdef HAVE_SEMAPHORE_UNNAMED
 	sem_destroy(current_sem);
+#  elif defined HAVE_SEMAPHORE_NAMED
+	if (current_sem) {
+		sem_unlink(SEMNAME_TOPLEVEL);
+		sem_close(current_sem);
+	}
+#  endif
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
 #pragma GCC diagnostic push
 #endif
@@ -788,17 +1638,37 @@ int main(int argc, char *argv[])
 #pragma GCC diagnostic pop
 #endif
 		fprintf(stderr, "\n\n"
-			"WARNING: Limiting max_threads to range acceptable for sem_init()\n\n");
+			"WARNING: Limiting max_threads to range acceptable for "
+			REPORT_SEM_INIT_METHOD "()\n\n");
 		max_threads = UINT_MAX - 1;
 	}
-	sem_init(current_sem, 0, (unsigned int)max_threads);
+
+	upsdebugx(1, "Parallel scan support: max_threads=%" PRIuSIZE, max_threads);
+#  ifdef HAVE_SEMAPHORE_UNNAMED
+	if (sem_init(current_sem, 0, (unsigned int)max_threads)) {
+		/* Show this one to end-users so they know */
+		upsdebug_with_errno(0, "Parallel scan support: " REPORT_SEM_INIT_METHOD "() failed");
+	}
+#  elif defined HAVE_SEMAPHORE_NAMED
+	/* FIXME: Do we need O_EXCL here? */
+	if (SEM_FAILED == (current_sem = sem_open(SEMNAME_TOPLEVEL, O_CREAT, 0644, (unsigned int)max_threads))) {
+		/* Show this one to end-users so they know */
+		upsdebug_with_errno(0, "Parallel scan support: " REPORT_SEM_INIT_METHOD "() failed");
+		current_sem = NULL;
+	}
+	nutscan_semaphore_set(current_sem);
+#  endif
+
 # endif
+#else
+	upsdebugx(1, "Parallel scan support: !HAVE_PTHREAD");
 #endif /* HAVE_PTHREAD */
 
-	if (cidr) {
-		upsdebugx(1, "Processing CIDR net/mask: %s", cidr);
-		nutscan_cidr_to_ip(cidr, &start_ip, &end_ip);
-		upsdebugx(1, "Extracted IP address range from CIDR net/mask: %s => %s", start_ip, end_ip);
+	if (start_ip != NULL || end_ip != NULL) {
+		/* Something did not cancel out above */
+		nutscan_add_ip_range(&ip_ranges_list, start_ip, end_ip);
+		start_ip = NULL;
+		end_ip = NULL;
 	}
 
 	if (!allow_usb && !allow_snmp && !allow_xml && !allow_oldnut && !allow_nut_simulation &&
@@ -809,6 +1679,11 @@ int main(int argc, char *argv[])
 
 	if (allow_all) {
 		allow_usb = 1;
+		/* NOTE: Starts as -1, so when we scan everything - set
+		 * it to 0 (minimal detail); further -U can bump it */
+		if (cli_link_detail_level < 0)
+			cli_link_detail_level++;
+
 		allow_snmp = 1;
 		allow_xml = 1;
 		allow_oldnut = 1;
@@ -830,15 +1705,16 @@ int main(int argc, char *argv[])
 		}
 #else
 		upsdebugx(1, "USB SCAN: no pthread support, starting nutscan_scan_usb...");
+		/* Not calling run_usb() here, as it re-processes the arg */
 		dev[TYPE_USB] = nutscan_scan_usb(&cli_link_detail_level);
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "USB SCAN: not requested, SKIPPED");
+		upsdebugx(1, "USB SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_snmp && nutscan_avail_snmp) {
-		if (start_ip == NULL) {
-			upsdebugx(quiet, "No start IP, skipping SNMP");
+		if (!ip_ranges_list.ip_ranges_count) {
+			upsdebugx(quiet, "No IP range(s) requested, skipping SNMP");
 			nutscan_avail_snmp = 0;
 		}
 		else {
@@ -851,14 +1727,20 @@ int main(int argc, char *argv[])
 			}
 #else
 			upsdebugx(1, "SNMP SCAN: no pthread support, starting nutscan_scan_snmp...");
-			dev[TYPE_SNMP] = nutscan_scan_snmp(start_ip, end_ip, timeout, &snmp_sec);
+			/* dev[TYPE_SNMP] = nutscan_scan_snmp(start_ip, end_ip, timeout, &snmp_sec); */
+			run_snmp(&snmp_sec);
 #endif /* HAVE_PTHREAD */
 		}
 	} else {
-		upsdebugx(1, "SNMP SCAN: not requested, SKIPPED");
+		upsdebugx(1, "SNMP SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_xml && nutscan_avail_xml_http) {
+		/* NOTE: No check for ip_ranges_count,
+		 * NetXML default scan is broadcast
+		 * so it just runs (if requested and
+		 * supported).
+		 */
 		upsdebugx(quiet, "Scanning XML/HTTP bus.");
 		xml_sec.usec_timeout = timeout;
 #ifdef HAVE_PTHREAD
@@ -869,19 +1751,21 @@ int main(int argc, char *argv[])
 		}
 #else
 		upsdebugx(1, "XML/HTTP SCAN: no pthread support, starting nutscan_scan_xml_http_range()...");
-		dev[TYPE_XML] = nutscan_scan_xml_http_range(start_ip, end_ip, timeout, &xml_sec);
+		/* dev[TYPE_XML] = nutscan_scan_xml_http_range(start_ip, end_ip, timeout, &xml_sec); */
+		run_xml(&xml_sec);
+		}
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "XML/HTTP SCAN: not requested, SKIPPED");
+		upsdebugx(1, "XML/HTTP SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_oldnut && nutscan_avail_nut) {
-		if (start_ip == NULL) {
-			upsdebugx(quiet, "No start IP, skipping NUT bus (old connect method)");
+		if (!ip_ranges_list.ip_ranges_count) {
+			upsdebugx(quiet, "No IP range(s) requested, skipping NUT bus (old libupsclient connect method)");
 			nutscan_avail_nut = 0;
 		}
 		else {
-			upsdebugx(quiet, "Scanning NUT bus (old connect method).");
+			upsdebugx(quiet, "Scanning NUT bus (old libupsclient connect method).");
 #ifdef HAVE_PTHREAD
 			upsdebugx(1, "NUT bus (old) SCAN: starting pthread_create with run_nut_old...");
 			if (pthread_create(&thread[TYPE_NUT], NULL, run_nut_old, NULL)) {
@@ -890,11 +1774,12 @@ int main(int argc, char *argv[])
 			}
 #else
 			upsdebugx(1, "NUT bus (old) SCAN: no pthread support, starting nutscan_scan_nut...");
-			dev[TYPE_NUT] = nutscan_scan_nut(start_ip, end_ip, port, timeout);
+			/*dev[TYPE_NUT] = nutscan_scan_nut(start_ip, end_ip, port, timeout);*/
+			run_nut_old(NULL);
 #endif /* HAVE_PTHREAD */
 		}
 	} else {
-		upsdebugx(1, "NUT bus (old) SCAN: not requested, SKIPPED");
+		upsdebugx(1, "NUT bus (old) SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_nut_simulation && nutscan_avail_nut_simulation) {
@@ -906,11 +1791,12 @@ int main(int argc, char *argv[])
 			nutscan_avail_nut_simulation = 0;
 		}
 #else
-			upsdebugx(1, "NUT simulation devices SCAN: no pthread support, starting nutscan_scan_nut_simulation...");
-			dev[TYPE_NUT_SIMULATION] = nutscan_scan_nut_simulation(timeout);
+		upsdebugx(1, "NUT simulation devices SCAN: no pthread support, starting nutscan_scan_nut_simulation...");
+		/* dev[TYPE_NUT_SIMULATION] = nutscan_scan_nut_simulation(); */
+		run_nut_simulation(NULL);
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "NUT simulation devices SCAN: not requested, SKIPPED");
+		upsdebugx(1, "NUT simulation devices SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_avahi && nutscan_avail_avahi) {
@@ -923,13 +1809,19 @@ int main(int argc, char *argv[])
 		}
 #else
 		upsdebugx(1, "NUT bus (avahi) SCAN: no pthread support, starting nutscan_scan_avahi...");
-		dev[TYPE_AVAHI] = nutscan_scan_avahi(timeout);
+		/* dev[TYPE_AVAHI] = nutscan_scan_avahi(timeout); */
+		run_avahi(NULL);
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "NUT bus (avahi) SCAN: not requested, SKIPPED");
+		upsdebugx(1, "NUT bus (avahi) SCAN: not requested or supported, SKIPPED");
 	}
 
 	if (allow_ipmi && nutscan_avail_ipmi) {
+		/* NOTE: No check for ip_ranges_count,
+		 * IPMI default scan is local device
+		 * so it just runs (if requested and
+		 * supported).
+		 */
 		upsdebugx(quiet, "Scanning IPMI bus.");
 #ifdef HAVE_PTHREAD
 		upsdebugx(1, "IPMI SCAN: starting pthread_create with run_ipmi...");
@@ -939,10 +1831,11 @@ int main(int argc, char *argv[])
 		}
 #else
 		upsdebugx(1, "IPMI SCAN: no pthread support, starting nutscan_scan_ipmi...");
-		dev[TYPE_IPMI] = nutscan_scan_ipmi(start_ip, end_ip, &ipmi_sec);
+		/* dev[TYPE_IPMI] = nutscan_scan_ipmi(start_ip, end_ip, &ipmi_sec); */
+		run_ipmi(&ipmi_sec);
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "IPMI SCAN: not requested, SKIPPED");
+		upsdebugx(1, "IPMI SCAN: not requested or supported, SKIPPED");
 	}
 
 	/* Eaton serial scan */
@@ -956,10 +1849,11 @@ int main(int argc, char *argv[])
 		/* nutscan_avail_eaton_serial(?) = 0; */
 #else
 		upsdebugx(1, "SERIAL SCAN: no pthread support, starting nutscan_scan_eaton_serial...");
-		dev[TYPE_EATON_SERIAL] = nutscan_scan_eaton_serial (serial_ports);
+		/* dev[TYPE_EATON_SERIAL] = nutscan_scan_eaton_serial (serial_ports); */
+		run_eaton_serial(serial_ports);
 #endif /* HAVE_PTHREAD */
 	} else {
-		upsdebugx(1, "SERIAL SCAN: not requested, SKIPPED");
+		upsdebugx(1, "SERIAL SCAN: not requested or supported, SKIPPED");
 	}
 
 #ifdef HAVE_PTHREAD
@@ -1040,12 +1934,19 @@ int main(int argc, char *argv[])
 	nutscan_free_device(dev[TYPE_EATON_SERIAL]);
 
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# ifdef HAVE_SEMAPHORE_UNNAMED
 	sem_destroy(nutscan_semaphore());
+# elif defined HAVE_SEMAPHORE_NAMED
+	if (nutscan_semaphore()) {
+		sem_unlink(SEMNAME_TOPLEVEL);
+		sem_close(nutscan_semaphore());
+		nutscan_semaphore_set(NULL);
+	}
 # endif
 #endif
 
 	upsdebugx(1, "SCANS DONE: free common scanner resources");
+	nutscan_free_ip_ranges(&ip_ranges_list);
 	nutscan_free();
 
 	upsdebugx(1, "SCANS DONE: EXIT_SUCCESS");
diff --git a/tools/nut-scanner/nutscan-device.c b/tools/nut-scanner/nutscan-device.c
index c01e229b98..47b1f6a7fa 100644
--- a/tools/nut-scanner/nutscan-device.c
+++ b/tools/nut-scanner/nutscan-device.c
@@ -1,6 +1,7 @@
 /*
- *  Copyright (C) 2011 - 2024 Arnaud Quette (Design and part of implementation)
+ *  Copyright (C) 2011-2024 Arnaud Quette (Design and part of implementation)
  *  Copyright (C) 2011 - EATON
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -25,6 +26,7 @@
 #include "config.h"	/* must be the first header */
 
 #include "nutscan-device.h"
+#include "common.h"
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
@@ -175,6 +177,11 @@ nutscan_device_t * nutscan_add_device_to_device(nutscan_device_t * first, nutsca
 	nutscan_device_t * dev1 = NULL;
 	nutscan_device_t * dev2 = NULL;
 
+	if (first == second) {
+		upsdebugx(5, "%s: skip: called to \"add\" same list pointers", __func__);
+		return first;
+	}
+
 	/* Get end of first device */
 	if (first != NULL) {
 		dev1 = first;
diff --git a/tools/nut-scanner/nutscan-device.h b/tools/nut-scanner/nutscan-device.h
index 4ab9bc714b..26f47d2ac6 100644
--- a/tools/nut-scanner/nutscan-device.h
+++ b/tools/nut-scanner/nutscan-device.h
@@ -1,6 +1,7 @@
 /*
- *  Copyright (C) 2011 - 2024 Arnaud Quette (Design and part of implementation)
+ *  Copyright (C) 2011-2024 Arnaud Quette (Design and part of implementation)
  *  Copyright (C) 2011 - EATON
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
diff --git a/tools/nut-scanner/nutscan-display.c b/tools/nut-scanner/nutscan-display.c
index bae9824bbb..f486b99198 100644
--- a/tools/nut-scanner/nutscan-display.c
+++ b/tools/nut-scanner/nutscan-display.c
@@ -1,6 +1,6 @@
 /*
  *  Copyright (C) 2011 - EATON
- *  2023 - Jim Klimov <jimklimov+nut@gmail.com>
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -261,9 +261,9 @@ void nutscan_display_sanity_check_serial(nutscan_device_t * device)
 	 */
 
 	/* Reserve enough slots for all-unique serials */
-	map = calloc(sizeof(keyval_strings_t), listlen);
+	map = calloc(listlen, sizeof(keyval_strings_t));
 	if (map == NULL) {
-		fprintf(stderr, "%s: Memory allocation error, skipped\n", __func__);
+		upsdebugx(0, "%s: Memory allocation error, skipped", __func__);
 		return;
 	}
 
@@ -317,7 +317,7 @@ void nutscan_display_sanity_check_serial(nutscan_device_t * device)
 					count++;
 					if (count != (i + 1) || count > listlen) {
 						/* Should never get here, but just in case... */
-						fprintf(stderr, "%s: Loop overflow, skipped\n", __func__);
+						upsdebugx(0, "%s: Loop overflow, skipped", __func__);
 						upsdebugx(3, "%s: count=%" PRIuSIZE " i=%" PRIuSIZE " listlen%" PRIuSIZE,
 							__func__, count, i, listlen);
 						goto exit;
diff --git a/tools/nut-scanner/nutscan-init.c b/tools/nut-scanner/nutscan-init.c
index 11efb6c894..5c81da464e 100644
--- a/tools/nut-scanner/nutscan-init.c
+++ b/tools/nut-scanner/nutscan-init.c
@@ -1,6 +1,8 @@
 /*
  *  Copyright (C) 2011 - 2024 Arnaud Quette (Design and part of implementation)
- *  Copyright (C) 2011-2021 - EATON
+ *  Copyright (C) 2011 - 2021 EATON
+ *  Copyright (C) 2016 - 2021 Jim Klimov <EvgenyKlimov@eaton.com>
+ *  Copyright (C) 2021 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -21,7 +23,8 @@
     \brief init functions for nut scanner library
     \author Frederic Bohe <fredericbohe@eaton.com>
     \author Arnaud Quette <ArnaudQuette@Eaton.com>
-	\author Arnaud Quette <arnaudquette@free.fr>
+    \author Arnaud Quette <arnaudquette@free.fr>
+    \author Jim Klimov <jimklimov+nut@gmail.com>
 */
 
 #include "common.h"
@@ -31,34 +34,47 @@
 #include <stdio.h>
 #include <string.h>
 #include "nut-scan.h"
+#include "nut_platform.h"
+#include "nut_stdint.h"
 
-#ifndef WIN32
-#define SOEXT ".so"
-#else
-#define SOEXT ".dll"
+/* Note: generated during build in $(top_builddir)/clients/
+ * and should be ensured to be here at the right moment by
+ * the nut-scanner Makefile. */
+#include "libupsclient-version.h"
+
+#ifdef WIN32
+# if defined HAVE_WINSOCK2_H && HAVE_WINSOCK2_H
+#  include <winsock2.h>
+# endif
 #endif
 
+/* Flags for code paths we can support in this run (libs available or not
+ * needed). For consistency, only set non-zero values via nutscan_init() call.
+ */
 int nutscan_avail_avahi = 0;
 int nutscan_avail_ipmi = 0;
-int nutscan_avail_nut = 0;
-int nutscan_avail_nut_simulation = 1;
-#ifdef WITH_SNMP_STATIC
-int nutscan_avail_snmp = 1;
-#else
+int nutscan_avail_nut = 0;	/* aka oldnut detection via libupsclient compared to avahi as newnut */
+int nutscan_avail_nut_simulation = 0;
 int nutscan_avail_snmp = 0;
-#endif
 int nutscan_avail_usb = 0;
 int nutscan_avail_xml_http = 0;
 
+/* Methods defined in scan_*.c source files */
 int nutscan_load_usb_library(const char *libname_path);
+int nutscan_unload_usb_library(void);
 int nutscan_load_snmp_library(const char *libname_path);
+int nutscan_unload_snmp_library(void);
 int nutscan_load_neon_library(const char *libname_path);
+int nutscan_unload_neon_library(void);
 int nutscan_load_avahi_library(const char *libname_path);
+int nutscan_unload_avahi_library(void);
 int nutscan_load_ipmi_library(const char *libname_path);
+int nutscan_unload_ipmi_library(void);
 int nutscan_load_upsclient_library(const char *libname_path);
+int nutscan_unload_upsclient_library(void);
 
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# ifdef HAVE_SEMAPHORE_UNNAMED
 /* Shared by library consumers, exposed by nutscan_semaphore() below */
 static sem_t semaphore;
 
@@ -66,13 +82,33 @@ sem_t * nutscan_semaphore(void)
 {
 	return &semaphore;
 }
-# endif /* HAVE_SEMAPHORE */
+
+void nutscan_semaphore_set(sem_t *s)
+{
+	NUT_UNUSED_VARIABLE(s);
+}
+# elif defined HAVE_SEMAPHORE_NAMED
+/* Shared by library consumers, exposed by nutscan_semaphore() below.
+ * Methods like sem_open() return the pointer and sem_close() frees its data.
+ */
+static sem_t *semaphore = NULL;	/* TOTHINK: maybe SEM_FAILED? */
+
+sem_t * nutscan_semaphore(void)
+{
+	return semaphore;
+}
+
+void nutscan_semaphore_set(sem_t *s)
+{
+	semaphore = s;
+}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 
 # ifdef HAVE_PTHREAD_TRYJOIN
 pthread_mutex_t threadcount_mutex;
 # endif
 
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 /* We have 3 networked scan types: nut, snmp, xml,
  * and users typically give their /24 subnet as "-m" arg.
  * With some systems having a 1024 default (u)limit to
@@ -95,8 +131,9 @@ size_t max_threads_netsnmp = 0; /* 10240; */
 	 * Still, some practical limit can be useful (configurable?)
 	 * Here 0 means to not apply any special limit (beside max_threads).
 	 */
+size_t max_threads_ipmi = 0;	/* limits not yet known */
 
-# endif  /* HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE */
+# endif  /* HAVE_PTHREAD_TRYJOIN || HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 
 #endif /* HAVE_PTHREAD */
 
@@ -107,12 +144,19 @@ void do_upsconf_args(char *confupsname, char *var, char *val) {
 	NUT_UNUSED_VARIABLE(var);
 	NUT_UNUSED_VARIABLE(val);
 }
-#endif
+#endif	/* WIN32 */
 
 void nutscan_init(void)
 {
 	char *libname = NULL;
 
+#ifdef WIN32
+	/* Required ritual before calling any socket functions */
+	WSADATA WSAdata;
+	WSAStartup(2,&WSAdata);
+	atexit((void(*)(void))WSACleanup);
+#endif
+
 	/* Optional filter to not walk things twice */
 	nut_prepare_search_paths();
 
@@ -124,7 +168,7 @@ void nutscan_init(void)
  * and the more naive but portable methods be an
  * if-else proposition? At least when initializing?
  */
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	/* NOTE: This semaphore may get re-initialized in nut-scanner program
 	 * after parsing command-line arguments. It calls nutscan_init() before
 	 * parsing CLI, to know about available libs and to set defaults below.
@@ -148,11 +192,24 @@ void nutscan_init(void)
 #pragma GCC diagnostic pop
 #endif
 		upsdebugx(1,
-			"WARNING: %s: Limiting max_threads to range acceptable for sem_init()",
+			"WARNING: %s: Limiting max_threads to range acceptable for " REPORT_SEM_INIT_METHOD "()",
 			__func__);
 		max_threads = UINT_MAX - 1;
 	}
-	sem_init(&semaphore, 0, (unsigned int)max_threads);
+
+	upsdebugx(1, "%s: Parallel scan support: max_threads=%" PRIuSIZE,
+		__func__, max_threads);
+#  ifdef HAVE_SEMAPHORE_UNNAMED
+	if (sem_init(&semaphore, 0, (unsigned int)max_threads)) {
+		upsdebug_with_errno(4, "%s: Parallel scan support: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+	}
+#  elif defined HAVE_SEMAPHORE_NAMED
+	/* FIXME: Do we need O_EXCL here? */
+	if (SEM_FAILED == (semaphore = sem_open(SEMNAME_TOPLEVEL, O_CREAT, 0644, (unsigned int)max_threads))) {
+		upsdebug_with_errno(4, "%s: Parallel scan support: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+		semaphore = NULL;
+	}
+#  endif
 # endif
 
 # ifdef HAVE_PTHREAD_TRYJOIN
@@ -160,192 +217,403 @@ void nutscan_init(void)
 # endif
 #endif	/* HAVE_PTHREAD */
 
+	/* Below we proceed to try loading dynamic libraries at run-time.
+	 * This allows a pre-built `nut-scanner` binary to not require all
+	 * of the possible NUT prerequisites to be installed on a system
+	 * (needlessly expanding its footprint) and allows to package the
+	 * tool with conservative formal dependencies.
+	 *
+	 * From the build time we can remember full SOPATH_LIB<X> and/or
+	 * base SOFILE_LIB<X> with specific library file names available
+	 * on the build system (with ".so.X.Y.Z" extensions or "libX-YZ.dll"
+	 * embedded version identifiers).
+	 *
+	 * Historically we allow run-time environments to override the
+	 * library search paths (e.g. for bundled NUT installers that
+	 * may be incompatible with OS library builds), so we use full
+	 * SOPATH_LIB<X> as the last option, but prefer a presumably
+	 * known-compatible SOFILE_LIB<X> first.
+	 */
+
 #ifdef WITH_USB
- #if WITH_LIBUSB_1_0
-	libname = get_libname("libusb-1.0" SOEXT);
- #else
-	libname = get_libname("libusb-0.1" SOEXT);
-  #ifdef WIN32
+# if WITH_LIBUSB_1_0
+
+#  ifdef SOFILE_LIBUSB1
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBUSB1);
+	}
+#  endif	/* SOFILE_LIBUSB1 */
+	if (!libname) {
+		libname = get_libname("libusb-1.0" SOEXT);
+	}
+#  ifdef SOPATH_LIBUSB1
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBUSB1);
+	}
+#  endif	/* SOPATH_LIBUSB1 */
+
+# else	/* not WITH_LIBUSB_1_0 => WITH_LIBUSB_0_1 */
+
+#  ifdef SOFILE_LIBUSB0
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBUSB0);
+	}
+#  endif	/* SOFILE_LIBUSB0 */
+	if (!libname) {
+		libname = get_libname("libusb-0.1" SOEXT);
+	}
+#  ifdef WIN32
 	/* TODO: Detect DLL name at build time, or rename it at install time? */
 	/* libusb-compat built for mingw per NUT instructions */
 	if (!libname) {
 		libname = get_libname("libusb-0-1-4" SOEXT);
 	}
-  #endif
- #endif
+#  endif	/* WIN32 */
+#  ifdef SOPATH_LIBUSB0
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBUSB0);
+	}
+#  endif	/* SOPATH_LIBUSB0 */
+# endif	/* WITH_LIBUSB_X_Y */
+
 	if (!libname) {
 		/* We can also use libusb-compat from newer libusb-1.0 releases */
 		libname = get_libname("libusb" SOEXT);
 	}
+
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "LibUSB");
 		nutscan_avail_usb = nutscan_load_usb_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "LibUSB");
- #if WITH_LIBUSB_1_0
-		nutscan_avail_usb = nutscan_load_usb_library("libusb-1.0" SOEXT);
- #else
-		nutscan_avail_usb = nutscan_load_usb_library("libusb-0.1" SOEXT);
-  #ifdef WIN32
+
+# if WITH_LIBUSB_1_0
+
+#  ifdef SOFILE_LIBUSB1
+		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library(SOFILE_LIBUSB1);
+		}
+#  endif	/* SOFILE_LIBUSB1 */
+		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library("libusb-1.0" SOEXT);
+		}
+#  ifdef SOPATH_LIBUSB1
+		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library(SOPATH_LIBUSB1);
+		}
+#  endif	/* SOPATH_LIBUSB1 */
+
+# else	/* not WITH_LIBUSB_1_0 => WITH_LIBUSB_0_1 */
+
+#  ifdef SOFILE_LIBUSB0
+		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library(SOFILE_LIBUSB0);
+		}
+#  endif	/* SOFILE_LIBUSB0 */
+		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library("libusb-0.1" SOEXT);
+		}
+#  ifdef WIN32
 		if (!nutscan_avail_usb) {
 			nutscan_avail_usb = nutscan_load_usb_library("libusb-0-1-4" SOEXT);
 		}
-  #endif
- #endif
+#  endif	/* WIN32 */
+#  ifdef SOPATH_LIBUSB0
 		if (!nutscan_avail_usb) {
+			nutscan_avail_usb = nutscan_load_usb_library(SOPATH_LIBUSB0);
+		}
+#  endif	/* SOPATH_LIBUSB0 */
+# endif	/* WITH_LIBUSB_X_Y */
+
+		if (!nutscan_avail_usb) {
+			/* We can also use libusb-compat from newer libusb-1.0 releases */
 			nutscan_avail_usb = nutscan_load_usb_library("libusb" SOEXT);
 		}
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_usb ? "succeeded" : "failed", "LibUSB");
-#else
+#else	/* not WITH_USB */
 	upsdebugx(1, "%s: skipped loading the library for %s: was absent during NUT build",
 		__func__, "LibUSB");
 #endif	/* WITH_USB */
 
 #ifdef WITH_SNMP
-	libname = get_libname("libnetsnmp" SOEXT);
- #ifdef WIN32
+# ifdef WITH_SNMP_STATIC
+	/* This is a rare situation, reserved for platforms where libnetsnmp or
+	 * equivalent (some other ucd-snmp descendants) was not packaged, and
+	 * thus was custom-built for NUT (so linked statically to avoid potential
+	 * conflicts with whatever else people may have practically deployed
+	 * nearby).
+	 */
+	upsdebugx(1, "%s: skipped loading the library for %s: was linked statically during NUT build",
+		__func__, "LibSNMP");
+	nutscan_avail_snmp = 1;
+# else	/* not WITH_SNMP_STATIC */
+#  ifdef SOFILE_LIBNETSNMP
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBNETSNMP);
+	}
+#  endif	/* SOFILE_LIBNETSNMP */
+	if (!libname) {
+		libname = get_libname("libnetsnmp" SOEXT);
+	}
+#  ifdef WIN32
 	if (!libname) {
 		libname = get_libname("libnetsnmp-40" SOEXT);
 	}
- #endif
+#  endif	/* WIN32 */
+#  ifdef SOPATH_LIBNETSNMP
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBNETSNMP);
+	}
+#  endif	/* SOPATH_LIBNETSNMP */
+
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "LibSNMP");
 		nutscan_avail_snmp = nutscan_load_snmp_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "LibSNMP");
-		nutscan_avail_snmp = nutscan_load_snmp_library("libnetsnmp" SOEXT);
-#ifdef WIN32
+#  ifdef SOFILE_LIBNETSNMP
+		if (!nutscan_avail_snmp) {
+			nutscan_avail_snmp = nutscan_load_snmp_library(SOFILE_LIBNETSNMP);
+		}
+#  endif	/* SOFILE_LIBNETSNMP */
+		if (!nutscan_avail_snmp) {
+			nutscan_avail_snmp = nutscan_load_snmp_library("libnetsnmp" SOEXT);
+		}
+#  ifdef WIN32
 		if (!nutscan_avail_snmp) {
 			nutscan_avail_snmp = nutscan_load_snmp_library("libnetsnmp-40" SOEXT);
 		}
-#endif
+#  endif	/* WIN32 */
+#  ifdef SOPATH_LIBNETSNMP
+		if (!nutscan_avail_snmp) {
+			nutscan_avail_snmp = nutscan_load_snmp_library(SOPATH_LIBNETSNMP);
+		}
+#  endif	/* SOPATH_LIBNETSNMP */
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_snmp ? "succeeded" : "failed", "LibSNMP");
-#else
+# endif	/* WITH_SNMP_STATIC */
+#else	/* not WITH_SNMP */
 	upsdebugx(1, "%s: skipped loading the library for %s: was absent during NUT build",
 		__func__, "LibSNMP");
 #endif	/* WITH_SNMP */
 
 #ifdef WITH_NEON
-	libname = get_libname("libneon" SOEXT);
+# ifdef SOFILE_LIBNEON
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBNEON);
+	}
+# endif	/* SOFILE_LIBNEON */
+	if (!libname) {
+		libname = get_libname("libneon" SOEXT);
+	}
 	if (!libname) {
 		libname = get_libname("libneon-gnutls" SOEXT);
 	}
- #ifdef WIN32
+# ifdef WIN32
 	if (!libname) {
 		libname = get_libname("libneon-27" SOEXT);
 	}
 	if (!libname) {
 		libname = get_libname("libneon-gnutls-27" SOEXT);
 	}
- #endif
+# endif	/* WIN32 */
+# ifdef SOPATH_LIBNEON
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBNEON);
+	}
+# endif	/* SOPATH_LIBNEON */
+
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "LibNeon");
 		nutscan_avail_xml_http = nutscan_load_neon_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "LibNeon");
-		nutscan_avail_xml_http = nutscan_load_neon_library("libneon" SOEXT);
+# ifdef SOFILE_LIBNEON
+		if (!nutscan_avail_xml_http) {
+			nutscan_avail_xml_http = nutscan_load_neon_library(SOFILE_LIBNEON);
+		}
+# endif	/* SOFILE_LIBNEON */
+		if (!nutscan_avail_xml_http) {
+			nutscan_avail_xml_http = nutscan_load_neon_library("libneon" SOEXT);
+		}
 		if (!nutscan_avail_xml_http) {
 			nutscan_avail_xml_http = nutscan_load_neon_library("libneon-gnutls" SOEXT);
 		}
-#ifdef WIN32
+# ifdef WIN32
 		if (!nutscan_avail_xml_http) {
 			nutscan_avail_xml_http = nutscan_load_neon_library("libneon-27" SOEXT);
 		}
 		if (!nutscan_avail_xml_http) {
 			nutscan_avail_xml_http = nutscan_load_neon_library("libneon-gnutls-27" SOEXT);
 		}
-#endif
+# endif	/* WIN32 */
+# ifdef SOPATH_LIBNEON
+		if (!nutscan_avail_xml_http) {
+			nutscan_avail_xml_http = nutscan_load_neon_library(SOPATH_LIBNEON);
+		}
+# endif	/* SOPATH_LIBNEON */
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_xml_http ? "succeeded" : "failed", "LibNeon");
-#else
+#else	/* not WITH_NEON */
 	upsdebugx(1, "%s: skipped loading the library for %s: was absent during NUT build",
 		__func__, "LibNeon");
 #endif	/* WITH_NEON */
 
 #ifdef WITH_AVAHI
-	libname = get_libname("libavahi-client" SOEXT);
+# ifdef SOFILE_LIBAVAHI
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBAVAHI);
+	}
+# endif	/* SOFILE_LIBAVAHI */
+	if (!libname) {
+		libname = get_libname("libavahi-client" SOEXT);
+	}
+# ifdef SOPATH_LIBAVAHI
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBAVAHI);
+	}
+# endif	/* SOPATH_LIBAVAHI */
+
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "LibAvahi");
 		nutscan_avail_avahi = nutscan_load_avahi_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "LibAvahi");
-		nutscan_avail_avahi = nutscan_load_avahi_library("libavahi-client" SOEXT);
+# ifdef SOFILE_LIBAVAHI
+		if (!nutscan_avail_avahi) {
+			nutscan_avail_avahi = nutscan_load_avahi_library(SOFILE_LIBAVAHI);
+		}
+# endif	/* SOFILE_LIBAVAHI */
+		if (!nutscan_avail_avahi) {
+			nutscan_avail_avahi = nutscan_load_avahi_library("libavahi-client" SOEXT);
+# ifdef SOPATH_LIBAVAHI
+		if (!nutscan_avail_avahi) {
+			nutscan_avail_avahi = nutscan_load_avahi_library(SOPATH_LIBAVAHI);
+		}
+# endif	/* SOPATH_LIBAVAHI */
+		}
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_avahi ? "succeeded" : "failed", "LibAvahi");
-#else
+#else	/* not WITH_AVAHI */
 	upsdebugx(1, "%s: skipped loading the library for %s: was absent during NUT build",
 		__func__, "LibAvahi");
 #endif	/* WITH_AVAHI */
 
 #ifdef WITH_FREEIPMI
-	libname = get_libname("libfreeipmi" SOEXT);
+# ifdef SOFILE_LIBFREEIPMI
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBFREEIPMI);
+	}
+# endif	/* SOFILE_LIBFREEIPMI */
+	if (!libname) {
+		libname = get_libname("libfreeipmi" SOEXT);
+	}
+# ifdef SOPATH_LIBFREEIPMI
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBFREEIPMI);
+	}
+# endif	/* SOPATH_LIBAVAHI */
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "LibFreeIPMI");
 		nutscan_avail_ipmi = nutscan_load_ipmi_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "LibFreeIPMI");
-		nutscan_avail_ipmi = nutscan_load_ipmi_library("libfreeipmi" SOEXT);
+# ifdef SOFILE_LIBFREEIPMI
+		if (!nutscan_avail_ipmi) {
+			nutscan_avail_ipmi = nutscan_load_ipmi_library(SOFILE_LIBFREEIPMI);
+		}
+# endif	/* SOFILE_LIBFREEIPMI */
+		if (!nutscan_avail_ipmi) {
+			nutscan_avail_ipmi = nutscan_load_ipmi_library("libfreeipmi" SOEXT);
+		}
+# ifdef SOPATH_LIBFREEIPMI
+		if (!nutscan_avail_ipmi) {
+			nutscan_avail_ipmi = nutscan_load_ipmi_library(SOPATH_LIBFREEIPMI);
+		}
+# endif	/* SOPATH_LIBFREEIPMI */
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_ipmi ? "succeeded" : "failed", "LibFreeIPMI");
-#else
+#else	/* not WITH_FREEIPMI */
 	upsdebugx(1, "%s: skipped loading the library for %s: was absent during NUT build",
 		__func__, "LibFreeIPMI");
 #endif	/* WITH_FREEIPMI */
 
 /* start of libupsclient for "old NUT" (vs. Avahi) protocol - unconditional */
-	libname = get_libname("libupsclient" SOEXT);
+#ifdef SOFILE_LIBUPSCLIENT
+	if (!libname) {
+		libname = get_libname(SOFILE_LIBUPSCLIENT);
+	}
+#endif	/* SOFILE_LIBUPSCLIENT */
+	if (!libname) {
+		libname = get_libname("libupsclient" SOEXT);
+	}
+#ifdef SOPATH_LIBUPSCLIENT
+	if (!libname) {
+		libname = get_libname(SOPATH_LIBUPSCLIENT);
+	}
+#endif	/* SOPATH_LIBUPSCLIENT */
 #ifdef WIN32
-	/* TODO: Detect DLL name at build time, or rename it at install time? */
-	/* e.g. see clients/Makefile.am for version-info value */
+	/* NOTE: Normally we should detect DLL name at build time,
+	 * see clients/Makefile.am for libupsclient-version.h */
 	if (!libname) {
 		libname = get_libname("libupsclient-6" SOEXT);
 	}
 	if (!libname) {
 		libname = get_libname("libupsclient-3" SOEXT);
 	}
-#endif
+#endif	/* WIN32 */
 	if (libname) {
 		upsdebugx(1, "%s: get_libname() resolved '%s' for %s, loading it",
 			__func__, libname, "NUT Client library");
 		nutscan_avail_nut = nutscan_load_upsclient_library(libname);
 		free(libname);
+		libname = NULL;
 	} else {
 		/* let libtool (lt_dlopen) do its default magic maybe better */
 		upsdebugx(1, "%s: get_libname() did not resolve libname for %s, "
 			"trying to load it with libtool default resolver",
 			__func__, "NUT Client library");
+#ifdef SOFILE_LIBUPSCLIENT
+		if (!nutscan_avail_nut) {
+			nutscan_avail_xml_http = nutscan_load_upsclient_library(SOFILE_LIBUPSCLIENT);
+		}
+#endif	/* SOFILE_LIBUPSCLIENT */
 		nutscan_avail_nut = nutscan_load_upsclient_library("libupsclient" SOEXT);
 #ifdef WIN32
 		if (!nutscan_avail_nut) {
@@ -354,7 +622,12 @@ void nutscan_init(void)
 		if (!nutscan_avail_nut) {
 			nutscan_avail_nut = nutscan_load_upsclient_library("libupsclient-3" SOEXT);
 		}
-#endif
+#endif	/* WIN32 */
+#ifdef SOPATH_LIBUPSCLIENT
+		if (!nutscan_avail_nut) {
+			nutscan_avail_xml_http = nutscan_load_upsclient_library(SOPATH_LIBUPSCLIENT);
+		}
+#endif	/* SOFILE_LIBUPSCLIENT */
 	}
 	upsdebugx(1, "%s: %s to load the library for %s",
 		__func__, nutscan_avail_nut ? "succeeded" : "failed", "NUT Client library");
@@ -363,35 +636,80 @@ void nutscan_init(void)
 
 /* start of "NUT Simulation" - unconditional */
 /* no need for additional library */
-	nutscan_avail_nut = 1;
-
+	nutscan_avail_nut_simulation = 1;
 }
 
-void nutscan_free(void)
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally to scan_* modules */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath)
 {
-	if (nutscan_avail_usb) {
-		lt_dlexit();
+	int ret = -1;
+
+	if (avail == NULL || pdl_handle == NULL) {
+		upsdebugx(1, "%s: called with bad inputs, no-op", __func__);
+		return -2;
 	}
-	if (nutscan_avail_snmp) {
-		lt_dlexit();
+
+	/* never tried/already unloaded */
+	if (*pdl_handle == NULL) {
+		goto end;
 	}
-	if (nutscan_avail_xml_http) {
-		lt_dlexit();
+
+	/* if previous init failed */
+	if (*pdl_handle == (void *)1) {
+		goto end;
 	}
-	if (nutscan_avail_avahi) {
-		lt_dlexit();
+
+	if (*avail == 0) {
+		upsdebugx(1, "%s: Asked to unload a module %p "
+			"for %s but our flag says it is not loaded",
+			__func__, (void *)(*pdl_handle),
+			(libpath && *libpath && **libpath)
+			? *libpath
+			: "<unidentified module>");
 	}
-	if (nutscan_avail_ipmi) {
-		lt_dlexit();
+
+	/* init has already been done */
+	if (libpath && *libpath && **libpath) {
+		upsdebugx(1, "%s: unloading module %s",
+			__func__, *libpath);
 	}
-	if (nutscan_avail_nut) {
-		lt_dlexit();
+	ret = lt_dlclose(*pdl_handle);
+	lt_dlexit();
+
+end:
+	*pdl_handle = NULL;
+	*avail = 0;
+
+	if (libpath && *libpath) {
+		free(*libpath);
+		*libpath = NULL;
 	}
 
+	return ret;
+}
+
+void nutscan_free(void)
+{
+	nutscan_unload_usb_library();
+	nutscan_unload_snmp_library();
+	nutscan_unload_neon_library();
+	nutscan_unload_avahi_library();
+	nutscan_unload_ipmi_library();
+	nutscan_unload_upsclient_library();
+
 #ifdef HAVE_PTHREAD
 /* TOTHINK: See comments near mutex/semaphore init code above */
-# ifdef HAVE_SEMAPHORE
+# ifdef HAVE_SEMAPHORE_UNNAMED
 	sem_destroy(nutscan_semaphore());
+# elif defined HAVE_SEMAPHORE_NAMED
+	if (nutscan_semaphore()) {
+		sem_unlink(SEMNAME_TOPLEVEL);
+		sem_close(nutscan_semaphore());
+		nutscan_semaphore_set(NULL);
+	}
 # endif
 
 # ifdef HAVE_PTHREAD_TRYJOIN
diff --git a/tools/nut-scanner/nutscan-ip.c b/tools/nut-scanner/nutscan-ip.c
index 4223bfa868..5c09a15134 100644
--- a/tools/nut-scanner/nutscan-ip.c
+++ b/tools/nut-scanner/nutscan-ip.c
@@ -1,5 +1,6 @@
 /*
  *  Copyright (C) 2011 - EATON
+ *  Copyright (C) 2022 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -65,12 +66,12 @@ static void invert_IPv6(struct in6_addr * addr1, struct in6_addr * addr2)
 
 static int ntop(struct in_addr * ip, char * host, GETNAMEINFO_TYPE_ARG46 host_size)
 {
-	struct sockaddr_in in;
-	memset(&in, 0, sizeof(struct sockaddr_in));
-	in.sin_addr = *ip;
-	in.sin_family = AF_INET;
+	struct sockaddr_in in4;
+	memset(&in4, 0, sizeof(struct sockaddr_in));
+	in4.sin_addr = *ip;
+	in4.sin_family = AF_INET;
 	return getnameinfo(
-		(struct sockaddr *)&in,
+		(struct sockaddr *)&in4,
 		sizeof(struct sockaddr_in),
 		host, host_size, NULL, 0, NI_NUMERICHOST);
 }
@@ -87,6 +88,252 @@ static int ntop6(struct in6_addr * ip, char * host, GETNAMEINFO_TYPE_ARG46 host_
 		host, host_size, NULL, 0, NI_NUMERICHOST);
 }
 
+/* Track requested IP ranges (from CLI or auto-discovery) */
+nutscan_ip_range_list_t *nutscan_init_ip_ranges(nutscan_ip_range_list_t *irl)
+{
+	if (!irl) {
+		irl = (nutscan_ip_range_list_t *)xcalloc(1, sizeof(nutscan_ip_range_list_t));
+	}
+
+	irl->ip_ranges = NULL;
+	irl->ip_ranges_last = NULL;
+	irl->ip_ranges_count = 0;
+
+	return irl;
+}
+
+void nutscan_free_ip_ranges(nutscan_ip_range_list_t *irl)
+{
+	nutscan_ip_range_t *p;
+
+	if (!irl) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_t was specified", __func__);
+		return;
+	}
+
+	p = irl->ip_ranges;
+	while (p) {
+		irl->ip_ranges = p->next;
+
+		/* Only free the strings once, if they pointed to same */
+		if (p->start_ip == p->end_ip && p->start_ip) {
+			free(p->start_ip);
+		} else {
+			if (p->start_ip)
+				free(p->start_ip);
+			if (p->end_ip)
+				free(p->end_ip);
+		}
+
+		free(p);
+		p = irl->ip_ranges;
+	}
+
+	irl->ip_ranges_last = NULL;
+	irl->ip_ranges_count = 0;
+}
+
+size_t nutscan_add_ip_range(nutscan_ip_range_list_t *irl, char * start_ip, char * end_ip)
+{
+	nutscan_ip_range_t *p;
+
+	if (!irl) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_t was specified", __func__);
+		return 0;
+	}
+
+	if (!start_ip && !end_ip) {
+		upsdebugx(5, "%s: skip, no addresses were provided", __func__);
+		return irl->ip_ranges_count;
+	}
+
+	if (start_ip == NULL) {
+		upsdebugx(5, "%s: only end address was provided, setting start to same: %s",
+			 __func__, end_ip);
+		start_ip = end_ip;
+	}
+	if (end_ip == NULL) {
+		upsdebugx(5, "%s: only start address was provided, setting end to same: %s",
+			 __func__, start_ip);
+		end_ip = start_ip;
+	}
+
+	p = xcalloc(1, sizeof(nutscan_ip_range_t));
+
+	if (start_ip == end_ip || strcmp(start_ip, end_ip) <= 0) {
+		p->start_ip = start_ip;
+		p->end_ip = end_ip;
+	} else {
+		p->start_ip = end_ip;
+		p->end_ip = start_ip;
+	}
+
+	p->next = NULL;
+
+	if (!irl->ip_ranges) {
+		/* First entry */
+		irl->ip_ranges = p;
+	}
+
+	if (irl->ip_ranges_last) {
+		/* Got earlier entries, promote the tail */
+		irl->ip_ranges_last->next = p;
+	}
+
+	irl->ip_ranges_last = p;
+	irl->ip_ranges_count++;
+
+	upsdebugx(1, "Recorded IP address range #%" PRIuSIZE ": [%s .. %s]",
+		irl->ip_ranges_count, start_ip, end_ip);
+
+	return irl->ip_ranges_count;
+}
+
+const char * nutscan_stringify_ip_ranges(nutscan_ip_range_list_t *irl)
+{
+	static char buf[LARGEBUF - 64];	/* Leave some space for upsdebugx() prefixes */
+	size_t	len = 0;
+
+	memset(buf, 0, sizeof(buf));
+	len += snprintf(buf + len, sizeof(buf) - len,
+		"(%" PRIuSIZE ")[",
+		(irl ? irl->ip_ranges_count : 0));
+
+	if (irl && irl->ip_ranges && irl->ip_ranges_count) {
+		nutscan_ip_range_t	*p;
+		size_t	j;
+
+		for (
+			j = 0, p = irl->ip_ranges;
+			p && len < sizeof(buf) - 6;
+			p = p->next, j++
+		 ) {
+			if (j) {
+				buf[len++] = ',';
+				buf[len++] = ' ';
+			}
+
+			if (len > sizeof(buf) - 6) {
+				/* Too little left, but enough for this */
+				buf[len++] = '.';
+				buf[len++] = '.';
+				buf[len++] = '.';
+				break;
+			}
+
+			if (p->start_ip == p->end_ip || !strcmp(p->start_ip, p->end_ip)) {
+				len += snprintf(buf + len, sizeof(buf) - len,
+					"%s", p->start_ip);
+			} else {
+				len += snprintf(buf + len, sizeof(buf) - len,
+					"%s .. %s", p->start_ip, p->end_ip);
+			}
+		}
+	}
+
+	if (len < sizeof(buf) - 1)
+		buf[len++] = ']';
+
+	return buf;
+}
+
+/* Return the first ip or NULL if error */
+char * nutscan_ip_ranges_iter_init(nutscan_ip_range_list_iter_t *irliter, const nutscan_ip_range_list_t *irl)
+{
+	char	*ip_str;
+
+	if (!irliter) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_iter_t was specified", __func__);
+		return NULL;
+	}
+
+	if (!irl) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_t was specified", __func__);
+		return NULL;
+	}
+
+	if (!irl->ip_ranges) {
+		upsdebugx(5, "%s: skip, empty nutscan_ip_range_list_t was specified", __func__);
+		return NULL;
+	}
+
+	memset(irliter, 0, sizeof(nutscan_ip_range_list_iter_t));
+	irliter->irl = irl;
+	irliter->ip_ranges_iter = irl->ip_ranges;
+	memset(&(irliter->curr_ip_iter), 0, sizeof(nutscan_ip_iter_t));
+
+	upsdebugx(4, "%s: beginning iteration with first IP range [%s .. %s]",
+		__func__, irliter->ip_ranges_iter->start_ip,
+		irliter->ip_ranges_iter->end_ip);
+
+	ip_str = nutscan_ip_iter_init(
+		&(irliter->curr_ip_iter),
+		irliter->ip_ranges_iter->start_ip,
+		irliter->ip_ranges_iter->end_ip);
+
+	upsdebugx(5, "%s: got IP from range: %s", __func__, NUT_STRARG(ip_str));
+	return ip_str;
+}
+
+/* return the next IP
+ * return NULL if there is no more IP
+ */
+char * nutscan_ip_ranges_iter_inc(nutscan_ip_range_list_iter_t *irliter)
+{
+	char	*ip_str;
+
+	if (!irliter) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_iter_t was specified", __func__);
+		return NULL;
+	}
+
+	if (!irliter->irl) {
+		upsdebugx(5, "%s: skip, no nutscan_ip_range_list_t was specified", __func__);
+		return NULL;
+	}
+
+	if (!irliter->irl->ip_ranges) {
+		upsdebugx(5, "%s: skip, empty nutscan_ip_range_list_t was specified", __func__);
+		return NULL;
+	}
+
+	if (!irliter->ip_ranges_iter) {
+		upsdebugx(5, "%s: skip, finished nutscan_ip_range_list_t was specified", __func__);
+		return NULL;
+	}
+
+	ip_str = nutscan_ip_iter_inc(&(irliter->curr_ip_iter));
+
+	if (ip_str) {
+		upsdebugx(5, "%s: got IP from range: %s", __func__, NUT_STRARG(ip_str));
+		return ip_str;
+	}
+
+	upsdebugx(5, "%s: end of IP range [%s .. %s]",
+		__func__, irliter->ip_ranges_iter->start_ip,
+		irliter->ip_ranges_iter->end_ip);
+
+	/* else: end of one range, try to switch to next */
+	irliter->ip_ranges_iter = irliter->ip_ranges_iter->next;
+	if (!(irliter->ip_ranges_iter)) {
+		upsdebugx(5, "%s: end of whole IP range list", __func__);
+		return NULL;
+	}
+
+	memset(&(irliter->curr_ip_iter), 0, sizeof(nutscan_ip_iter_t));
+	upsdebugx(4, "%s: beginning iteration with next IP range [%s .. %s]",
+		__func__, irliter->ip_ranges_iter->start_ip,
+		irliter->ip_ranges_iter->end_ip);
+
+	ip_str = nutscan_ip_iter_init(
+		&(irliter->curr_ip_iter),
+		irliter->ip_ranges_iter->start_ip,
+		irliter->ip_ranges_iter->end_ip);
+
+	upsdebugx(5, "%s: got IP from range: %s", __func__, NUT_STRARG(ip_str));
+	return ip_str;
+}
+
 /* Return the first ip or NULL if error */
 char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const char * stopIP)
 {
@@ -94,10 +341,17 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 	int i;
 	struct addrinfo hints;
 	struct addrinfo *res;
-	struct sockaddr_in * s_in;
-	struct sockaddr_in6 * s_in6;
 	char host[SMALLBUF];
 
+	/* Ensure proper alignment of IPvN structure fields:
+	 * we receive a pointer to res from getaddrinfo() et al,
+	 * so have no control about alignment of its further data.
+	 * Make a copy of the bytes into an object allocated
+	 * whichever way the system likes it.
+	 */
+	struct sockaddr_in	s_in4buf, *s_in4 = &s_in4buf;
+	struct sockaddr_in6	s_in6buf, *s_in6 = &s_in6buf;
+
 	if (startIP == NULL) {
 		return NULL;
 	}
@@ -116,35 +370,18 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 		ip->type = IPv6;
 		hints.ai_family = AF_INET6;
 		if (getaddrinfo(startIP, NULL, &hints, &res) != 0) {
-			fprintf(stderr, "Invalid address : %s\n", startIP);
+			upsdebugx(0, "WARNING: %s: Invalid address : %s",
+				__func__, startIP);
 			return NULL;
 		}
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in6 = (struct sockaddr_in6 *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+		memcpy(s_in6, res->ai_addr, sizeof(struct sockaddr_in6));
 		memcpy(&ip->start6, &s_in6->sin6_addr, sizeof(struct in6_addr));
 		freeaddrinfo(res);
 	}
 	else {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in = (struct sockaddr_in *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
-		ip->start = s_in->sin_addr;
+		memcpy(s_in4, res->ai_addr, sizeof(struct sockaddr_in));
+		ip->start = s_in4->sin_addr;
 		freeaddrinfo(res);
 	}
 
@@ -152,39 +389,23 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 	if (ip->type == IPv4) {
 		hints.ai_family = AF_INET;
 		if (getaddrinfo(stopIP, NULL, &hints, &res) != 0) {
-			fprintf(stderr, "Invalid address : %s\n", stopIP);
+			upsdebugx(0, "WARNING: %s: Invalid address : %s",
+				__func__, stopIP);
 			return NULL;
 		}
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in = (struct sockaddr_in *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
-		ip->stop = s_in->sin_addr;
+		memcpy(s_in4, res->ai_addr, sizeof(struct sockaddr_in));
+		ip->stop = s_in4->sin_addr;
 		freeaddrinfo(res);
 	}
 	else {
 		hints.ai_family = AF_INET6;
 		if (getaddrinfo(stopIP, NULL, &hints, &res) != 0) {
-			fprintf(stderr, "Invalid address : %s\n", stopIP);
+			upsdebugx(0, "WARNING: %s: Invalid address : %s",
+				__func__, stopIP);
 			return NULL;
 		}
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in6 = (struct sockaddr_in6 *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+		memcpy(s_in6, res->ai_addr, sizeof(struct sockaddr_in6));
 		memcpy(&ip->stop6, &s_in6->sin6_addr, sizeof(struct in6_addr));
 		freeaddrinfo(res);
 	}
@@ -204,6 +425,7 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 		return strdup(host);
 	}
 	else { /* IPv6 */
+		size_t	hlen;
 		for (i = 0; i < 16; i++) {
 			if (ip->start6.s6_addr[i] !=ip->stop6.s6_addr[i]) {
 				if (ip->start6.s6_addr[i] > ip->stop6.s6_addr[i]) {
@@ -213,9 +435,17 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 			}
 		}
 
-		if (ntop6(&ip->start6, host, sizeof(host)) != 0) {
+		/* IPv6 addresses must be in square brackets,
+		 * for upsclient et al to differentiate them
+		 * from the port number.
+		 */
+		host[0] = '[';
+		if (ntop6(&ip->start6, host + 1, sizeof(host) - 2) != 0) {
 			return NULL;
 		}
+		hlen = strlen(host);
+		host[hlen] = ']';
+		host[hlen + 1] = '\0';
 
 		return strdup(host);
 	}
@@ -223,8 +453,8 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t * ip, const char * startIP, const
 }
 
 /* return the next IP
-return NULL if there is no more IP
-*/
+ * return NULL if there is no more IP
+ */
 char * nutscan_ip_iter_inc(nutscan_ip_iter_t * ip)
 {
 	char host[SMALLBUF];
@@ -245,6 +475,8 @@ char * nutscan_ip_iter_inc(nutscan_ip_iter_t * ip)
 		return strdup(host);
 	}
 	else {
+		size_t	hlen;
+
 		/* Check if this is the last address to scan */
 		if (memcmp(&ip->start6.s6_addr, &ip->stop6.s6_addr,
 				sizeof(ip->start6.s6_addr)) == 0) {
@@ -252,9 +484,18 @@ char * nutscan_ip_iter_inc(nutscan_ip_iter_t * ip)
 		}
 
 		increment_IPv6(&ip->start6);
-		if (ntop6(&ip->start6, host, sizeof(host)) != 0) {
+
+		/* IPv6 addresses must be in square brackets,
+		 * for upsclient et al to differentiate them
+		 * from the port number.
+		 */
+		host[0] = '[';
+		if (ntop6(&ip->start6, host + 1, sizeof(host) - 2) != 0) {
 			return NULL;
 		}
+		hlen = strlen(host);
+		host[hlen] = ']';
+		host[hlen + 1] = '\0';
 
 		return strdup(host);
 	}
@@ -267,21 +508,31 @@ int nutscan_cidr_to_ip(const char * cidr, char ** start_ip, char ** stop_ip)
 	char * mask;
 	char * saveptr = NULL;
 	nutscan_ip_iter_t ip;
-	int mask_val;
-	int mask_byte;
 	int ret;
-	uint32_t mask_bit; /* 32-bit IPv4 address bitmask */
+	int mask_val;	/* mask length in bits */
+	int mask_byte;	/* number of byte in 128-bit IPv6 address array (uint8_t[16]) for netmask */
+	uint32_t mask_bit; /* 32-bit IPv4 address bitmask value */
 	char host[SMALLBUF];
 	struct addrinfo hints;
 	struct addrinfo *res;
-	struct sockaddr_in * s_in;
-	struct sockaddr_in6 * s_in6;
+
+	/* Ensure proper alignment of IPvN structure fields:
+	 * we receive a pointer to res from getaddrinfo() et al,
+	 * so have no control about alignment of its further data.
+	 * Make a copy of the bytes into an object allocated
+	 * whichever way the system likes it.
+	 */
+	struct sockaddr_in	s_in4buf, *s_in4 = &s_in4buf;
+	struct sockaddr_in6	s_in6buf, *s_in6 = &s_in6buf;
 
 	*start_ip = NULL;
 	*stop_ip = NULL;
-#ifdef WIN32
-        WSADATA WSAdata;
-#endif
+
+	if (!cidr) {
+		upsdebugx(0, "WARNING: %s: null cidr pointer was provided",
+			__func__);
+		return 0;
+	}
 
 	cidr_tok = strdup(cidr);
 	first_ip = strdup(strtok_r(cidr_tok, "/", &saveptr));
@@ -295,15 +546,24 @@ int nutscan_cidr_to_ip(const char * cidr, char ** start_ip, char ** stop_ip)
 	if (mask == NULL) {
 		upsdebugx(0, "WARNING: %s failed to parse mask from cidr=%s (first_ip=%s)",
 			__func__, cidr, first_ip);
-		free (first_ip);
+		free(first_ip);
 		free(cidr_tok);
 		return 0;
 	}
+
+	if (first_ip[0] == '[' && first_ip[strlen(first_ip) - 1] == ']') {
+		char *s = strdup(first_ip + 1);
+		s[strlen(s) - 1] = '\0';
+		free(first_ip);
+		first_ip = s;
+	}
+
 	upsdebugx(5, "%s: parsed cidr=%s into first_ip=%s and mask=%s",
 		__func__, cidr, first_ip, mask);
 
+	/* TODO: check if mask is also an IP address or a bit count */
 	mask_val = atoi(mask);
-	upsdebugx(5, "%s: parsed mask value %d",
+	upsdebugx(5, "%s: parsed mask into numeric value %d",
 		__func__, mask_val);
 
 	/* NOTE: Sanity-wise, some larger number also makes sense
@@ -324,51 +584,28 @@ int nutscan_cidr_to_ip(const char * cidr, char ** start_ip, char ** stop_ip)
 
 	ip.type = IPv4;
 
-#ifdef WIN32
-        WSAStartup(2,&WSAdata);
-        atexit((void(*)(void))WSACleanup);
-#endif
-
 	if ((ret = getaddrinfo(first_ip, NULL, &hints, &res)) != 0) {
 		/* EAI_ADDRFAMILY? */
-		upsdebugx(5, "%s: getaddrinfo() failed for AF_INET (IPv4): %d",
-			__func__, ret);
+		upsdebugx(5, "%s: getaddrinfo() failed for AF_INET (IPv4, will retry with IPv6): %d: %s",
+			__func__, ret, gai_strerror(ret));
 
 		/* Try IPv6 detection */
 		ip.type = IPv6;
 		hints.ai_family = AF_INET6;
 		if ((ret = getaddrinfo(first_ip, NULL, &hints, &res)) != 0) {
-			upsdebugx(5, "%s: getaddrinfo() failed for AF_INET6 (IPv6): %d",
-				__func__, ret);
+			upsdebugx(5, "%s: getaddrinfo() failed for AF_INET6 (IPv6): %d: %s",
+				__func__, ret, gai_strerror(ret));
 			free(first_ip);
 			return 0;
 		}
 
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in6 = (struct sockaddr_in6 *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+		memcpy(s_in6, res->ai_addr, sizeof(struct sockaddr_in6));
 		memcpy(&ip.start6, &s_in6->sin6_addr, sizeof(struct in6_addr));
 		freeaddrinfo(res);
 	}
 	else {
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in = (struct sockaddr_in *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
-		ip.start = s_in->sin_addr;
+		memcpy(s_in4, res->ai_addr, sizeof(struct sockaddr_in));
+		ip.start = s_in4->sin_addr;
 		freeaddrinfo(res);
 	}
 
@@ -404,20 +641,12 @@ int nutscan_cidr_to_ip(const char * cidr, char ** start_ip, char ** stop_ip)
 		free(first_ip);
 		return 1;
 	}
-	else {
+	else {	/* ip.type == IPv6 */
 		if (getaddrinfo(first_ip, NULL, &hints, &res) != 0) {
 			return 0;
 		}
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wcast-align"
-#endif
-		/* Note: we receive a pointer to res above, so have
-		 * no control about alignment of its further data */
-		s_in6 = (struct sockaddr_in6 *)res->ai_addr;
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_CAST_ALIGN)
-# pragma GCC diagnostic pop
-#endif
+
+		memcpy(s_in6, res->ai_addr, sizeof(struct sockaddr_in6));
 		memcpy(&ip.stop6, &s_in6->sin6_addr, sizeof(struct in6_addr));
 		freeaddrinfo(res);
 
diff --git a/tools/nut-scanner/nutscan-ip.h b/tools/nut-scanner/nutscan-ip.h
index 8cdf6d8498..a6b8876090 100644
--- a/tools/nut-scanner/nutscan-ip.h
+++ b/tools/nut-scanner/nutscan-ip.h
@@ -1,5 +1,6 @@
 /*
  *  Copyright (C) 2011 - EATON
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -56,6 +57,56 @@ char * nutscan_ip_iter_init(nutscan_ip_iter_t *, const char * startIP, const cha
 char * nutscan_ip_iter_inc(nutscan_ip_iter_t *);
 int nutscan_cidr_to_ip(const char * cidr, char ** start_ip, char ** stop_ip);
 
+/* Track requested IP ranges (from CLI or auto-discovery) */
+/* One IP address range: */
+typedef struct nutscan_ip_range_s {
+	char * start_ip;
+	char * end_ip;
+	struct nutscan_ip_range_s * next;
+} nutscan_ip_range_t;
+
+/* List of IP address ranges and helper data: */
+typedef struct nutscan_ip_range_list_s {
+	nutscan_ip_range_t * ip_ranges;		/* Actual linked list of entries, first entry */
+	nutscan_ip_range_t * ip_ranges_last;	/* Pointer to end of list for quicker additions */
+	size_t ip_ranges_count;			/* Counter of added entries */
+} nutscan_ip_range_list_t;
+
+/* Initialize fields of caller-provided list
+ * (can allocate one if arg is NULL - caller
+ * must free it later). Does not assume that
+ * caller's list values are valid and should
+ * be freed (can be some garbage from stack).
+ *
+ * Returns pointer to the original or allocated list.
+ */
+nutscan_ip_range_list_t *nutscan_init_ip_ranges(nutscan_ip_range_list_t *irl);
+
+/* Free information from the list (does not
+ * free the list object itself, can be static)
+ * so it can be further re-used or freed.
+ */
+void nutscan_free_ip_ranges(nutscan_ip_range_list_t *irl);
+
+/* Prints contents of irl into a groovy-like string,
+ * using a static buffer (rewritten by each call) */
+const char * nutscan_stringify_ip_ranges(nutscan_ip_range_list_t *irl);
+
+size_t nutscan_add_ip_range(nutscan_ip_range_list_t *irl, char * start_ip, char * end_ip);
+
+/* Iterator over given nutscan_ip_range_list_t structure
+ * and the currently pointed-to range in its list.
+ * Several iterators may use the same range.
+ */
+typedef struct nutscan_ip_range_list_iter_s {
+	const nutscan_ip_range_list_t * irl;	/* Structure with actual linked list of address-range entries */
+	nutscan_ip_range_t * ip_ranges_iter;	/* Helper for iteration: across the list of IP ranges */
+	nutscan_ip_iter_t    curr_ip_iter;	/* Helper for iteration: across one currently iterated IP range */
+} nutscan_ip_range_list_iter_t;
+
+char * nutscan_ip_ranges_iter_init(nutscan_ip_range_list_iter_t *irliter, const nutscan_ip_range_list_t *irl);
+char * nutscan_ip_ranges_iter_inc(nutscan_ip_range_list_iter_t *irliter);
+
 #ifdef __cplusplus
 /* *INDENT-OFF* */
 }
diff --git a/tools/nut-scanner/nutscan-serial.c b/tools/nut-scanner/nutscan-serial.c
index a98b4dcb29..b354752ada 100644
--- a/tools/nut-scanner/nutscan-serial.c
+++ b/tools/nut-scanner/nutscan-serial.c
@@ -42,7 +42,7 @@
 #define SERIAL_PORT_PREFIX "/dev/tty"
 #endif
 
-#define ERR_OUT_OF_BOUND "Serial port range out of bound (must be 0 to 9 or a to z depending on your system)\n"
+#define ERR_OUT_OF_BOUND "Serial port range out of bound (must be 0 to 9 or a to z depending on your system)"
 
 typedef struct {
 	char * name;
@@ -108,7 +108,7 @@ static char ** add_port(char ** list, char * port)
 	/*+1 for the terminal NULL */
 	res = realloc(list, sizeof(char*) * (count + 1 + 1));
 	if (res == NULL) {
-		upsdebugx(1, "%s: Failed to realloc port list", __func__);
+		upsdebugx(0, "%s: Failed to realloc port list", __func__);
 		return list;
 	}
 	res[count] = strdup(port);
@@ -146,7 +146,7 @@ char ** nutscan_get_serial_ports_list(const char *ports_range)
 		if ((list_sep_ptr = strchr(range, '-')) != NULL) {
 			tok = strtok_r(range, "-", &saveptr);
 			if (tok[1] != 0) {
-				fprintf(stderr, ERR_OUT_OF_BOUND);
+				upsdebugx(0, "%s", ERR_OUT_OF_BOUND);
 				free(range);
 				return NULL;
 			}
@@ -154,7 +154,7 @@ char ** nutscan_get_serial_ports_list(const char *ports_range)
 			tok = strtok_r(NULL, "-", &saveptr);
 			if (tok != NULL) {
 				if (tok[1] != 0) {
-					fprintf(stderr, ERR_OUT_OF_BOUND);
+					upsdebugx(0, "%s", ERR_OUT_OF_BOUND);
 					free(range);
 					return NULL;
 				}
diff --git a/tools/nut-scanner/scan_avahi.c b/tools/nut-scanner/scan_avahi.c
index 1c41fc0d40..16e5261261 100644
--- a/tools/nut-scanner/scan_avahi.c
+++ b/tools/nut-scanner/scan_avahi.c
@@ -1,6 +1,7 @@
 /*
- *  Copyright (C) 2011 - 2024 Arnaud Quette (Design and part of implementation)
+ *  Copyright (C) 2011-2024 Arnaud Quette (Design and part of implementation)
  *  Copyright (C) 2011 - EATON
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -26,6 +27,9 @@
 #include "common.h"
 #include "nut-scan.h"
 
+/* externally visible to nutscan-init */
+int nutscan_unload_avahi_library(void);
+
 #ifdef WITH_AVAHI
 
 #include <stdio.h>
@@ -47,6 +51,7 @@
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
+static char *dl_saved_libname = NULL;
 
 static AvahiClient* (*nut_avahi_service_browser_get_client)(AvahiServiceBrowser *);
 static int (*nut_avahi_simple_poll_loop)(AvahiSimplePoll *s);
@@ -90,7 +95,16 @@ static int (*nut_avahi_service_browser_free)(AvahiServiceBrowser *);
 static char * (*nut_avahi_address_snprint)(char *ret_s, size_t length, const AvahiAddress *a);
 static const AvahiPoll* (*nut_avahi_simple_poll_get)(AvahiSimplePoll *s);
 
-/* return 0 on error; visible externally */
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_avahi_library(void)
+{
+	return nutscan_unload_library(&nutscan_avail_avahi, &dl_handle, &dl_saved_libname);
+}
+
+/* Return 0 on error; visible externally */
 int nutscan_load_avahi_library(const char *libname_path);
 int nutscan_load_avahi_library(const char *libname_path)
 {
@@ -104,12 +118,12 @@ int nutscan_load_avahi_library(const char *libname_path)
 	}
 
 	if (libname_path == NULL) {
-		fprintf(stderr, "AVAHI client library not found. AVAHI search disabled.\n");
+		upsdebugx(0, "AVAHI client library not found. AVAHI search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-		fprintf(stderr, "Error initializing lt_init\n");
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
 		return 0;
 	}
 
@@ -118,7 +132,10 @@ int nutscan_load_avahi_library(const char *libname_path)
 		dl_error = lt_dlerror();
 		goto err;
 	}
-	lt_dlerror();      /* Clear any existing error */
+
+	/* Clear any existing error */
+	lt_dlerror();
+
 	*(void **) (&nut_avahi_service_browser_get_client) = lt_dlsym(dl_handle, "avahi_service_browser_get_client");
 	if ((dl_error = lt_dlerror()) != NULL) {
 		goto err;
@@ -209,13 +226,22 @@ int nutscan_load_avahi_library(const char *libname_path)
 		goto err;
 	}
 
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
+
 	return 1;
+
 err:
-	fprintf(stderr,
-		"Cannot load AVAHI library (%s) : %s. AVAHI search disabled.\n",
+	upsdebugx(0,
+		"Cannot load AVAHI library (%s) : %s. AVAHI search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 }
 /* end of dynamic link library stuff */
@@ -382,23 +408,23 @@ static void resolve_callback(
 
 	switch (event) {
 		case AVAHI_RESOLVER_FAILURE:
-			fprintf(stderr,
-				"(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s\n",
-				name, type, domain,
+			upsdebugx(0, "%s: "
+				"(Resolver) Failed to resolve service '%s' of type '%s' in domain '%s': %s",
+				__func__, name, type, domain,
 				(*nut_avahi_strerror)((*nut_avahi_client_errno)((*nut_avahi_service_resolver_get_client)(r))));
 			break;
 
-		case AVAHI_RESOLVER_FOUND: {
+		case AVAHI_RESOLVER_FOUND: { /* scoping */
 			char a[AVAHI_ADDRESS_STR_MAX], *t;
 
-/*			fprintf(stderr, "Service '%s' of type '%s' in domain '%s':\n", name, type, domain); */
+/*			upsdebugx(1, "%s: Service '%s' of type '%s' in domain '%s':", __func__, name, type, domain); */
 
 			(*nut_avahi_address_snprint)(a, sizeof(a), address);
 			t = (*nut_avahi_string_list_to_string)(txt);
 
 			NUT_UNUSED_VARIABLE(flags);
 /*
-			fprintf(stderr,
+			upsdebugx(1,
 				"\t%s:%u (%s)\n"
 				"\tTXT=%s\n"
 				"\tcookie is %u\n"
@@ -418,7 +444,33 @@ static void resolve_callback(
 */
 			update_device(host_name, a, port, t, address->proto);
 			(*nut_avahi_free)(t);
-		}
+			}
+			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
+			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 
 	(*nut_avahi_service_resolver_free)(r);
@@ -446,14 +498,14 @@ static void browse_callback(
 	switch (event) {
 		case AVAHI_BROWSER_FAILURE:
 
-			fprintf(stderr,
-				"(Browser) %s\n",
+			upsdebugx(0, "%s: (Browser) %s",
+				__func__,
 				(*nut_avahi_strerror)((*nut_avahi_client_errno)((*nut_avahi_service_browser_get_client)(b))));
 			(*nut_avahi_simple_poll_quit)(simple_poll);
 			return;
 
 		case AVAHI_BROWSER_NEW:
-/*			fprintf(stderr, "(Browser) NEW: service '%s' of type '%s' in domain '%s'\n", name, type, domain); */
+/*			upsdebugx(1, "%s: "(Browser) NEW: service '%s' of type '%s' in domain '%s'", __func__, name, type, domain); */
 
 			/* We ignore the returned resolver object. In the callback
 			   function we free it. If the server is terminated before
@@ -473,14 +525,15 @@ static void browse_callback(
 #if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
 # pragma GCC diagnostic pop
 #endif
-				fprintf(stderr,
-					"Failed to resolve service '%s': %s\n",
+				upsdebugx(0, "%s: "
+					"Failed to resolve service '%s': %s",
+					__func__,
 					name, (*nut_avahi_strerror)((*nut_avahi_client_errno)(c)));
 
 			break;
 
 		case AVAHI_BROWSER_REMOVE:
-			fprintf(stderr, "(Browser) REMOVE: service '%s' of type '%s' in domain '%s'\n", name, type, domain);
+			upsdebugx(0, "%s: (Browser) REMOVE: service '%s' of type '%s' in domain '%s'", __func__, name, type, domain);
 			break;
 
 		case AVAHI_BROWSER_ALL_FOR_NOW:
@@ -489,8 +542,33 @@ static void browse_callback(
 
 		case AVAHI_BROWSER_CACHE_EXHAUSTED:
 		fallthrough_AVAHI_BROWSER_CACHE_EXHAUSTED:
-/*			fprintf(stderr, "(Browser) %s\n", event == AVAHI_BROWSER_CACHE_EXHAUSTED ? "CACHE_EXHAUSTED" : "ALL_FOR_NOW"); */
+/*			upsdebugx(1, "%s: (Browser) %s", __func__, event == AVAHI_BROWSER_CACHE_EXHAUSTED ? "CACHE_EXHAUSTED" : "ALL_FOR_NOW"); */
+			break;
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT
+# pragma GCC diagnostic ignored "-Wcovered-switch-default"
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+# pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+/* Older CLANG (e.g. clang-3.4) seems to not support the GCC pragmas above */
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunreachable-code"
+# pragma clang diagnostic ignored "-Wcovered-switch-default"
+#endif
+		default:
+			/* Must not occur. */
 			break;
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_COVERED_SWITCH_DEFAULT) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE) )
+# pragma GCC diagnostic pop
+#endif
 	}
 }
 
@@ -501,13 +579,32 @@ static void client_callback(AvahiClient *c, AvahiClientState state, void * userd
 	/* Called whenever the client or server state changes */
 
 	if (state == AVAHI_CLIENT_FAILURE) {
-		fprintf(stderr,
-			"Server connection failure: %s\n",
+		upsdebugx(0, "%s: "
+			"Server connection failure: %s",
+			__func__,
 			(*nut_avahi_strerror)((*nut_avahi_client_errno)(c)));
 		(*nut_avahi_simple_poll_quit)(simple_poll);
 	}
 }
 
+static AvahiClient* wrap_nut_avahi_client_new(int *error)
+{
+	/* Allocate a new client */
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wassign-enum"
+#endif
+	/* It seems that avahi-common/defs.h only defines the flags in a
+	 * manner similar to bitmask flags to request certain features,
+	 * but lacks a value in that enum for lack of flags (unconstrained
+	 * lookup). So we have to silence a warning here...
+	 */
+	return (*nut_avahi_client_new)((*nut_avahi_simple_poll_get)(simple_poll), 0, client_callback, NULL, error);
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
+# pragma GCC diagnostic pop
+#endif
+}
+
 nutscan_device_t * nutscan_scan_avahi(useconds_t usec_timeout)
 {
 	/* Example service publication
@@ -525,30 +622,19 @@ nutscan_device_t * nutscan_scan_avahi(useconds_t usec_timeout)
 
 	/* Allocate main loop object */
 	if (!(simple_poll = (*nut_avahi_simple_poll_new)())) {
-		fprintf(stderr, "Failed to create Avahi simple poll object.\n");
+		upsdebugx(0, "%s: Failed to create Avahi simple poll object.",
+			__func__);
 		goto fail;
 	}
 
 	/* Allocate a new client */
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
-# pragma GCC diagnostic push
-# pragma GCC diagnostic ignored "-Wassign-enum"
-#endif
-	/* It seems that avahi-common/defs.h only defines the flags in a
-	 * manner similar to bitmask flags to request certain features,
-	 * but lacks a value in that enum for lack of flags (unconstrained
-	 * lookup). So we have to silence a warning here...
-	 */
-	client = (*nut_avahi_client_new)((*nut_avahi_simple_poll_get)(simple_poll), 0, client_callback, NULL, &error);
-#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
-# pragma GCC diagnostic pop
-#endif
+	client = wrap_nut_avahi_client_new(&error);
 
 	/* Check wether creating the client object succeeded */
 	if (!client) {
-		fprintf(stderr,
-			"Failed to create Avahi client: %s\n",
-			(*nut_avahi_strerror)(error));
+		upsdebugx(0, "%s: "
+			"Failed to create Avahi client: %s",
+			__func__, (*nut_avahi_strerror)(error));
 		goto fail;
 	}
 
@@ -565,8 +651,9 @@ nutscan_device_t * nutscan_scan_avahi(useconds_t usec_timeout)
 #if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ASSIGN_ENUM)
 # pragma GCC diagnostic pop
 #endif
-		fprintf(stderr,
-			"Failed to create Avahi service browser: %s\n",
+		upsdebugx(0, "%s: "
+			"Failed to create Avahi service browser: %s",
+			__func__,
 			(*nut_avahi_strerror)((*nut_avahi_client_errno)(client)));
 		goto fail;
 	}
@@ -599,4 +686,8 @@ nutscan_device_t * nutscan_scan_avahi(useconds_t usec_timeout)
 	return NULL;
 }
 
+int nutscan_unload_avahi_library(void)
+{
+	return 0;
+}
 #endif /* WITH_AVAHI */
diff --git a/tools/nut-scanner/scan_eaton_serial.c b/tools/nut-scanner/scan_eaton_serial.c
index fad55f3e11..2c462522fc 100644
--- a/tools/nut-scanner/scan_eaton_serial.c
+++ b/tools/nut-scanner/scan_eaton_serial.c
@@ -1,6 +1,7 @@
 /*
  *  Copyright (C) 2012 - EATON
  *  Copyright (C) 2016-2021 - EATON - Various threads-related improvements
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -29,7 +30,7 @@
 
 /* Need this on AIX when using xlc to get alloca */
 #ifdef _AIX
-#pragma alloca
+# pragma alloca
 #endif /* _AIX */
 
 #include <fcntl.h>
@@ -379,7 +380,14 @@ static nutscan_device_t * nutscan_scan_eaton_serial_q1(const char* port_name)
 	return dev;
 }
 
-static void * nutscan_scan_eaton_serial_device(void * port_arg)
+/* Wrap calls to actual implementations of nutscan_scan_eaton_serial_shut(),
+ * nutscan_scan_eaton_serial_xcp() and/or nutscan_scan_eaton_serial_q1()
+ * which implement the semantics of parallel-able scanning.
+ * Returns the device entry, updates global dev_ret when a scan is successful.
+ * DOES NOT FREE the caller's copy of "port_arg", unlike many similar methods
+ * in other scanners.
+ */
+static void * nutscan_scan_eaton_serial_device_thready(void * port_arg)
 {
 	nutscan_device_t * dev = NULL;
 	char* port_name = (char*) port_arg;
@@ -395,6 +403,7 @@ static void * nutscan_scan_eaton_serial_device(void * port_arg)
 		}
 		/* Else try UTalk? */
 	}
+
 	return dev;
 }
 
@@ -408,10 +417,15 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 	char *current_port_name = NULL;
 	char **serial_ports_list;
 	int  current_port_nb;
+
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	sem_t * semaphore = nutscan_semaphore();
-# endif
+	/* TODO? Port semaphore_scantype / max_threads_scantype
+	 *  from sibling sources? We do not have that many serial
+	 *  ports to care much, usually... right?
+	 */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 	pthread_t thread;
 	nutscan_thread_t * thread_array = NULL;
 	size_t thread_count = 0, i;
@@ -453,7 +467,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 		 * for below in pthread_join()...
 		 */
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 		/* Just wait for someone to free a semaphored slot,
 		 * if none are available, and then/otherwise grab one
 		 */
@@ -484,6 +498,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 				"(launched overall: %" PRIuSIZE "), "
 				"waiting until some would finish",
 				__func__, curr_threads, thread_count);
+
 			while (curr_threads >= max_threads) {
 				for (i = 0; i < thread_count ; i++) {
 					int ret;
@@ -491,7 +506,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 					if (!thread_array[i].active) continue;
 
 					pthread_mutex_lock(&threadcount_mutex);
-					upsdebugx(3, "%s: Trying to join thread #%i...", __func__, i);
+					upsdebugx(3, "%s: Trying to join thread #%" PRIuSIZE "...", __func__, i);
 					ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
 					switch (ret) {
 						case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
@@ -528,17 +543,18 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 			}
 			upsdebugx(2, "%s: proceeding with scan", __func__);
 		}
+
 		/* NOTE: No change to default "pass" in this ifdef:
 		 * if we got to this line, we have a slot to use */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 
 		if (pass) {
 			current_port_name = serial_ports_list[current_port_nb];
 
 #ifdef HAVE_PTHREAD
-			if (pthread_create(&thread, NULL, nutscan_scan_eaton_serial_device, (void*)current_port_name) == 0) {
+			if (pthread_create(&thread, NULL, nutscan_scan_eaton_serial_device_thready, (void*)current_port_name) == 0) {
 				nutscan_thread_t	*new_thread_array;
 # ifdef HAVE_PTHREAD_TRYJOIN
 				pthread_mutex_lock(&threadcount_mutex);
@@ -563,17 +579,20 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 # endif /* HAVE_PTHREAD_TRYJOIN */
 			}
 #else   /* if not HAVE_PTHREAD */
-			nutscan_scan_eaton_serial_device(current_port_name);
+			nutscan_scan_eaton_serial_device_thready(current_port_name);
 #endif  /* if HAVE_PTHREAD */
+
+			/* Prepare the next iteration */
 			current_port_nb++;
 		} else { /* if not pass -- all slots busy */
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			/* Wait for all current scans to complete */
 			if (thread_array != NULL) {
-				upsdebugx (2, "%s: Running too many scanning threads, "
+				upsdebugx (2, "%s: Running too many scanning threads (%"
+					PRIuSIZE "), "
 					"waiting until older ones would finish",
-					__func__);
+					__func__, thread_count);
 				for (i = 0; i < thread_count ; i++) {
 					int ret;
 					if (!thread_array[i].active) {
@@ -600,7 +619,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 #  ifdef HAVE_PTHREAD_TRYJOIN
 			/* TODO: Move the wait-loop for TRYJOIN here? */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 		} /* if: could we "pass" or not? */
 	} /* while */
@@ -619,7 +638,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 					__func__, ret);
 			}
 			thread_array[i].active = FALSE;
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			sem_post(semaphore);
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
@@ -634,7 +653,7 @@ nutscan_device_t * nutscan_scan_eaton_serial(const char* ports_range)
 			}
 			pthread_mutex_unlock(&threadcount_mutex);
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif /* HAVE_SEMAPHORE */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 		}
 		free(thread_array);
 		upsdebugx(2, "%s: all threads freed", __func__);
diff --git a/tools/nut-scanner/scan_ipmi.c b/tools/nut-scanner/scan_ipmi.c
index ba4e50776f..0d40bfa63f 100644
--- a/tools/nut-scanner/scan_ipmi.c
+++ b/tools/nut-scanner/scan_ipmi.c
@@ -1,6 +1,8 @@
 /*
  *  Copyright (C)
  *    2011 - 2012  Arnaud Quette <arnaud.quette@free.fr>
+ *    2016 - 2021  EATON - Various threads-related improvements
+ *    2020 - 2024  Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -24,12 +26,16 @@
 
 #include "common.h"
 #include "nut-scan.h"
+#include "nut_stdint.h"
+
+/* externally visible to nutscan-init */
+int nutscan_unload_ipmi_library(void);
 
 #ifdef WITH_IPMI
-#include "upsclient.h"
+
 #include <freeipmi/freeipmi.h>
-#include <stdio.h>
 #include <string.h>
+#include <stdio.h>
 #include <ltdl.h>
 
 #define NUT_IPMI_DRV_NAME	"nut-ipmipsu"
@@ -42,34 +48,35 @@
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
+static char *dl_saved_libname = NULL;
 
 #ifdef HAVE_FREEIPMI_11X_12X
   /* Functions symbols remapping */
-  #define IPMI_FRU_CLOSE_DEVICE_ID                     "ipmi_fru_close_device_id"
-  #define IPMI_FRU_CTX_DESTROY                         "ipmi_fru_ctx_destroy"
-  #define IPMI_FRU_CTX_CREATE                          "ipmi_fru_ctx_create"
-  #define IPMI_FRU_CTX_SET_FLAGS                       "ipmi_fru_ctx_set_flags"
-  #define IPMI_FRU_OPEN_DEVICE_ID                      "ipmi_fru_open_device_id"
-  #define IPMI_FRU_CTX_ERRORMSG                        "ipmi_fru_ctx_errormsg"
-  #define IPMI_FRU_READ_DATA_AREA                      "ipmi_fru_read_data_area"
-  #define IPMI_FRU_PARSE_NEXT                          "ipmi_fru_next"
+#  define IPMI_FRU_CLOSE_DEVICE_ID                     "ipmi_fru_close_device_id"
+#  define IPMI_FRU_CTX_DESTROY                         "ipmi_fru_ctx_destroy"
+#  define IPMI_FRU_CTX_CREATE                          "ipmi_fru_ctx_create"
+#  define IPMI_FRU_CTX_SET_FLAGS                       "ipmi_fru_ctx_set_flags"
+#  define IPMI_FRU_OPEN_DEVICE_ID                      "ipmi_fru_open_device_id"
+#  define IPMI_FRU_CTX_ERRORMSG                        "ipmi_fru_ctx_errormsg"
+#  define IPMI_FRU_READ_DATA_AREA                      "ipmi_fru_read_data_area"
+#  define IPMI_FRU_PARSE_NEXT                          "ipmi_fru_next"
   typedef ipmi_fru_ctx_t ipmi_fru_parse_ctx_t;
   typedef ipmi_sdr_ctx_t ipmi_sdr_cache_ctx_t;
   /* Functions remapping */
   static void (*nut_ipmi_sdr_ctx_destroy) (ipmi_sdr_ctx_t ctx);
 #else /* HAVE_FREEIPMI_11X_12X */
-  #define IPMI_FRU_AREA_SIZE_MAX                                   IPMI_FRU_PARSE_AREA_SIZE_MAX
-  #define IPMI_FRU_FLAGS_SKIP_CHECKSUM_CHECKS                      IPMI_FRU_PARSE_FLAGS_SKIP_CHECKSUM_CHECKS
-  #define IPMI_FRU_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION  IPMI_FRU_PARSE_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION
+#  define IPMI_FRU_AREA_SIZE_MAX                                   IPMI_FRU_PARSE_AREA_SIZE_MAX
+#  define IPMI_FRU_FLAGS_SKIP_CHECKSUM_CHECKS                      IPMI_FRU_PARSE_FLAGS_SKIP_CHECKSUM_CHECKS
+#  define IPMI_FRU_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION  IPMI_FRU_PARSE_AREA_TYPE_MULTIRECORD_POWER_SUPPLY_INFORMATION
   /* Functions symbols remapping */
-  #define IPMI_FRU_CLOSE_DEVICE_ID                     "ipmi_fru_parse_close_device_id"
-  #define IPMI_FRU_CTX_DESTROY                         "ipmi_fru_parse_ctx_destroy"
-  #define IPMI_FRU_CTX_CREATE                          "ipmi_fru_parse_ctx_create"
-  #define IPMI_FRU_CTX_SET_FLAGS                       "ipmi_fru_parse_ctx_set_flags"
-  #define IPMI_FRU_OPEN_DEVICE_ID                      "ipmi_fru_parse_open_device_id"
-  #define IPMI_FRU_CTX_ERRORMSG                        "ipmi_fru_parse_ctx_errormsg"
-  #define IPMI_FRU_READ_DATA_AREA                      "ipmi_fru_parse_read_data_area"
-  #define IPMI_FRU_PARSE_NEXT                          "ipmi_fru_parse_next"
+#  define IPMI_FRU_CLOSE_DEVICE_ID                     "ipmi_fru_parse_close_device_id"
+#  define IPMI_FRU_CTX_DESTROY                         "ipmi_fru_parse_ctx_destroy"
+#  define IPMI_FRU_CTX_CREATE                          "ipmi_fru_parse_ctx_create"
+#  define IPMI_FRU_CTX_SET_FLAGS                       "ipmi_fru_parse_ctx_set_flags"
+#  define IPMI_FRU_OPEN_DEVICE_ID                      "ipmi_fru_parse_open_device_id"
+#  define IPMI_FRU_CTX_ERRORMSG                        "ipmi_fru_parse_ctx_errormsg"
+#  define IPMI_FRU_READ_DATA_AREA                      "ipmi_fru_parse_read_data_area"
+#  define IPMI_FRU_PARSE_NEXT                          "ipmi_fru_parse_next"
   /* Functions remapping */
   static void (*nut_ipmi_sdr_cache_ctx_destroy) (ipmi_sdr_cache_ctx_t ctx);
   static void (*nut_ipmi_sdr_parse_ctx_destroy) (ipmi_sdr_parse_ctx_t ctx);
@@ -112,8 +119,32 @@ static char * (*nut_ipmi_ctx_errormsg) (ipmi_ctx_t ctx);
 static int (*nut_ipmi_ctx_close) (ipmi_ctx_t ctx);
 static void (*nut_ipmi_ctx_destroy) (ipmi_ctx_t ctx);
 
+/* This variable collects device(s) from a sequential or parallel scan,
+ * is returned to caller, and cleared to allow subsequent independent scans */
+static nutscan_device_t * dev_ret = NULL;
+#ifdef HAVE_PTHREAD
+static pthread_mutex_t dev_mutex;
+#endif
+
+/* use explicit booleans */
+#ifndef FALSE
+typedef enum ebool { FALSE = 0, TRUE } bool_t;
+#else
+typedef int bool_t;
+#endif
+
 /* Internal functions */
 static nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t * sec);
+static void * nutscan_scan_ipmi_device_thready(void * arg_sec);
+
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_ipmi_library(void)
+{
+	return nutscan_unload_library(&nutscan_avail_ipmi, &dl_handle, &dl_saved_libname);
+}
 
 /* Return 0 on error; visible externally */
 int nutscan_load_ipmi_library(const char *libname_path);
@@ -129,12 +160,12 @@ int nutscan_load_ipmi_library(const char *libname_path)
 	}
 
 	if (libname_path == NULL) {
-		fprintf(stderr, "IPMI library not found. IPMI search disabled.\n");
+		upsdebugx(0, "IPMI library not found. IPMI search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-		fprintf(stderr, "Error initializing lt_init\n");
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
 		return 0;
 	}
 
@@ -242,13 +273,22 @@ int nutscan_load_ipmi_library(const char *libname_path)
 			goto err;
 	}
 
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
+
 	return 1;
+
 err:
-	fprintf(stderr,
-		"Cannot load IPMI library (%s) : %s. IPMI search disabled.\n",
+	upsdebugx(0,
+		"Cannot load IPMI library (%s) : %s. IPMI search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 }
 /* end of dynamic link library stuff */
@@ -305,7 +345,9 @@ static int is_ipmi_device_supported(ipmi_ctx_t ipmi_ctx, int ipmi_id)
 	/* Parse FRU information */
 	if (!(fru_parse_ctx = (*nut_ipmi_fru_ctx_create) (ipmi_ctx)))
 	{
-		fprintf(stderr, "Error with %s(): %s\n", IPMI_FRU_CTX_CREATE, (*nut_ipmi_ctx_errormsg)(ipmi_ctx));
+		upsdebugx(0, "%s: Error with %s(): %s",
+			__func__, IPMI_FRU_CTX_CREATE,
+			(*nut_ipmi_ctx_errormsg)(ipmi_ctx));
 		return 0;
 	}
 
@@ -321,7 +363,8 @@ static int is_ipmi_device_supported(ipmi_ctx_t ipmi_ctx, int ipmi_id)
 	}
 
 	if (ipmi_id < 0 || (unsigned int)ipmi_id > UINT8_MAX) {
-		fprintf(stderr, "is_ipmi_device_supported: ipmi_id=%d is out of range!\n", ipmi_id);
+		upsdebugx(0, "%s: ipmi_id=%d is out of range!",
+			__func__, ipmi_id);
 		return 0;
 	}
 	if ((*nut_ipmi_fru_open_device_id) (fru_parse_ctx, (uint8_t)ipmi_id) < 0)
@@ -380,6 +423,11 @@ static int is_ipmi_device_supported(ipmi_ctx_t ipmi_ctx, int ipmi_id)
 	return 0;
 }
 
+static ipmi_ctx_t wrap_nut_ipmi_ctx_create(void)
+{
+	return (*nut_ipmi_ctx_create) ();
+}
+
 /* Check for IPMI support on a specific (local or remote) system
  * Return NULL on error, or a valid nutscan_device_t otherwise */
 nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t * ipmi_sec)
@@ -396,19 +444,21 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 	}
 
 	/* Initialize the FreeIPMI library. */
-	if (!(ipmi_ctx = (*nut_ipmi_ctx_create) ()))
+	if (!(ipmi_ctx = wrap_nut_ipmi_ctx_create()))
 	{
 		/* we have to force cleanup, since exit handler is not yet installed */
-		fprintf(stderr, "Failed to ipmi_ctx_create\n");
+		upsdebugx(0, "%s: Failed to ipmi_ctx_create", __func__);
 		return NULL;
 	}
 
 	/* Are we scanning locally, or over the network? */
 	if (IPaddr == NULL)
 	{
+		upsdebugx(2, "Entering %s for local device scan", __func__);
+
 		/* FIXME: we need root right to access local IPMI!
 		if (!ipmi_is_root ()) {
-			fprintf(stderr, "IPMI scan: %s\n", ipmi_ctx_strerror (IPMI_ERR_PERMISSION));
+			upsdebugx(0, "%s: IPMI scan: %s", __func__, ipmi_ctx_strerror (IPMI_ERR_PERMISSION));
 		} */
 
 		if ((ret = (*nut_ipmi_ctx_find_inband) (ipmi_ctx,
@@ -433,6 +483,8 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 	}
 	else {
 
+		upsdebugx(2, "Entering %s for %s", __func__, IPaddr);
+
 #if 0
 		if (ipmi_sec->ipmi_version == IPMI_2_0) {
 
@@ -440,7 +492,7 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 			 * int parse_kg (void *out, unsigned int outlen, const char *in)
 			 * if ((rv = parse_kg (common_cmd_args_config->k_g, IPMI_MAX_K_G_LENGTH + 1, data->string)) < 0)
 			 * {
-			 * 	fprintf (stderr, "Config File Error: k_g input formatted incorrectly\n");
+			 * 	upsdebugx(0, "%s: Config File Error: k_g input formatted incorrectly", __func__);
 			 * 	exit (EXIT_FAILURE);
 			 * }*/
 			if ((ret = (*nut_ipmi_ctx_open_outofband_2_0) (ipmi_ctx,
@@ -556,7 +608,7 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 		if (is_ipmi_device_supported(ipmi_ctx, ipmi_id)) {
 
 			if ((nut_dev = nutscan_new_device()) == NULL) {
-				fprintf(stderr, "Memory allocation error\n");
+				upsdebugx(0, "%s: Memory allocation error", __func__);
 				nutscan_free_device(current_nut_dev);
 				break;
 			}
@@ -569,6 +621,8 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 			}
 			else {
 				/* FIXME: also check against "localhost" and its IPv{4,6} */
+				/* FIXME: Should the IPv6 address here be bracketed?
+				 *  Does our driver support the notation? */
 				sprintf(port_id, "id%x@%s", ipmi_id, IPaddr);
 			}
 			nut_dev->port = strdup(port_id);
@@ -581,7 +635,6 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 
 			memset (port_id, 0, sizeof(port_id));
 		}
-
 	}
 
 	/* Final cleanup */
@@ -593,45 +646,435 @@ nutscan_device_t * nutscan_scan_ipmi_device(const char * IPaddr, nutscan_ipmi_t
 	return current_nut_dev;
 }
 
+/* Wrap calls to nutscan_scan_ipmi_device() into semantics for parallel-able
+ * scanning. Returns NULL, updates global dev_ret when a scan is successful.
+ * FREES the caller's copy of "sec" and "peername" in it, if applicable.
+ */
+static void * nutscan_scan_ipmi_device_thready(void * arg_sec)
+{
+	nutscan_device_t	*dev = NULL;
+	nutscan_ipmi_t	*sec = (nutscan_ipmi_t *)arg_sec;
+
+	if (sec == NULL || sec->peername == NULL)
+		dev = nutscan_scan_ipmi_device(NULL, NULL);
+	else
+		dev = nutscan_scan_ipmi_device(sec->peername, sec);
+
+	if (dev) {
+#ifdef HAVE_PTHREAD
+		pthread_mutex_lock(&dev_mutex);
+#endif
+		dev_ret = nutscan_add_device_to_device(dev_ret, dev);
+#ifdef HAVE_PTHREAD
+		pthread_mutex_unlock(&dev_mutex);
+#endif
+	}
+
+	if (sec) {
+		if (sec->peername) {
+			free(sec->peername);
+		}
+		free(sec);
+	}
+
+	return NULL;
+}
+
 /* General IPMI scan entry point: scan 1 to n devices, local or remote,
  * for IPMI support
  * Return NULL on error, or a valid nutscan_device_t otherwise */
 nutscan_device_t * nutscan_scan_ipmi(const char * start_ip, const char * stop_ip, nutscan_ipmi_t * sec)
 {
-	nutscan_ip_iter_t ip;
-	char * ip_str = NULL;
-	nutscan_ipmi_t * tmp_sec;
-	nutscan_device_t * nut_dev = NULL;
-	nutscan_device_t * current_nut_dev = NULL;
+	nutscan_device_t	*ndret;
+
+	/* Are we scanning locally, or through the network? */
+	if (start_ip || stop_ip) {
+		nutscan_ip_range_list_t irl;
+
+		nutscan_init_ip_ranges(&irl);
+		nutscan_add_ip_range(&irl, (char *)start_ip, (char *)stop_ip);
+
+		ndret = nutscan_scan_ip_range_ipmi(&irl, sec);
+
+		/* Avoid nuking caller's strings here */
+		irl.ip_ranges->start_ip = NULL;
+		irl.ip_ranges->end_ip = NULL;
+		nutscan_free_ip_ranges(&irl);
+	} else {
+		/* Probe local device */
+		ndret = nutscan_scan_ip_range_ipmi(NULL, sec);
+	}
+
+	return ndret;
+}
+
+/* General IPMI scan entry point: scan 1 to n devices, local or remote,
+ * for IPMI support
+ * Return NULL on error, or a valid nutscan_device_t otherwise */
+nutscan_device_t * nutscan_scan_ip_range_ipmi(nutscan_ip_range_list_t * irl, nutscan_ipmi_t * sec)
+{
+	bool_t pass = TRUE; /* Track that we may spawn a scanning thread */
+	nutscan_device_t * result = NULL;
+	nutscan_ipmi_t * tmp_sec = NULL;
 
 	if (!nutscan_avail_ipmi) {
 		return NULL;
 	}
 
+	/* Are we scanning locally, or through the network?
+	 * We assume the list is maintained by our methods, so should not have
+	 * null addresses. But just in case - check for it a little tiny once.
+	 */
+	if (irl == NULL || irl->ip_ranges == NULL
+	 || irl->ip_ranges->start_ip == NULL || irl->ip_ranges->end_ip == NULL
+	) {
+		upsdebugx(1, "%s: Local PSU scan", __func__);
+		nutscan_scan_ipmi_device_thready(NULL);
+	} else {
+		/* Iterate the one or a range of IPs to scan */
+		nutscan_ip_range_list_iter_t ip;
+		char * ip_str = NULL;
+
+#ifdef HAVE_PTHREAD
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		sem_t * semaphore = nutscan_semaphore();
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+		sem_t   semaphore_scantype_inst;
+		sem_t * semaphore_scantype = &semaphore_scantype_inst;
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		sem_t * semaphore_scantype = NULL;
+#  endif
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+		pthread_t thread;
+		nutscan_thread_t * thread_array = NULL;
+		size_t thread_count = 0, i;
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		size_t  max_threads_scantype = max_threads_ipmi;
+# endif
+#endif	/* HAVE_PTHREAD */
+
+		if (irl->ip_ranges_count == 1
+		&& (irl->ip_ranges->start_ip == irl->ip_ranges->end_ip
+		    || !strcmp(irl->ip_ranges->start_ip, irl->ip_ranges->end_ip)
+		)) {
+			upsdebugx(1, "%s: Scanning remote PSU for single IP address: %s",
+				__func__, irl->ip_ranges->start_ip);
+		} else {
+			upsdebugx(1, "%s: Scanning remote PSU for IP address range(s): %s",
+				__func__, nutscan_stringify_ip_ranges(irl));
+		}
+
+#ifdef HAVE_PTHREAD
+		pthread_mutex_init(&dev_mutex, NULL);
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		if (max_threads_scantype > 0) {
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+			/* Different platforms, different sizes, none fits all... */
+			if (SIZE_MAX > UINT_MAX && max_threads_scantype > UINT_MAX) {
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
+				upsdebugx(1,
+					"WARNING: %s: Limiting max_threads_scantype to range acceptable for " REPORT_SEM_INIT_METHOD "()",
+					__func__);
+				max_threads_scantype = UINT_MAX - 1;
+			}
 
-	/* Are we scanning locally, or through the network? */
-	if (start_ip == NULL)
-	{
-		/* Local PSU scan */
-		current_nut_dev = nutscan_scan_ipmi_device(NULL, NULL);
-	}
-	else {
-		ip_str = nutscan_ip_iter_init(&ip, start_ip, stop_ip);
+			upsdebugx(4, "%s: " REPORT_SEM_INIT_METHOD "() for %" PRIuSIZE " threads", __func__, max_threads_scantype);
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+			if (sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype)) {
+				upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+				max_threads_scantype = 0;
+			}
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+			if (SEM_FAILED == (semaphore_scantype = sem_open(SEMNAME_IPMI, O_CREAT, 0644, (unsigned int)max_threads_scantype))) {
+				upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+				semaphore_scantype = NULL;
+				max_threads_scantype = 0;
+			}
+#  endif
+		}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+
+#endif /* HAVE_PTHREAD */
+
+		ip_str = nutscan_ip_ranges_iter_init(&ip, irl);
 
 		while (ip_str != NULL) {
-			tmp_sec = malloc(sizeof(nutscan_ipmi_t));
-			memcpy(tmp_sec, sec, sizeof(nutscan_ipmi_t));
+#ifdef HAVE_PTHREAD
+			/* NOTE: With many enough targets to scan, this can crash
+			 * by spawning too many children; add a limit and loop to
+			 * "reap" some already done with their work. And probably
+			 * account them in thread_array[] as something to not wait
+			 * for below in pthread_join()...
+			 */
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+			/* Just wait for someone to free a semaphored slot,
+			 * if none are available, and then/otherwise grab one
+			 */
+			if (thread_array == NULL) {
+				/* Starting point, or after a wait to complete
+				 * all earlier runners */
+				if (max_threads_scantype > 0)
+					sem_wait(semaphore_scantype);
+				sem_wait(semaphore);
+				pass = TRUE;
+			} else {
+				/* If successful (the lock was acquired),
+				 * sem_wait() and sem_trywait() will return 0.
+				 * Otherwise, -1 is returned and errno is set,
+				 * and the state of the semaphore is unchanged.
+				 */
+				int	stwST = sem_trywait(semaphore_scantype);
+				int	stwS  = sem_trywait(semaphore);
+				pass = ((max_threads_scantype == 0 || stwST == 0) && stwS == 0);
+				upsdebugx(4, "%s: max_threads_scantype=%" PRIuSIZE
+					" curr_threads=%" PRIuSIZE
+					" thread_count=%" PRIuSIZE
+					" stwST=%d stwS=%d pass=%d",
+					__func__, max_threads_scantype,
+					curr_threads, thread_count,
+					stwST, stwS, pass
+				);
+			}
+# else
+#  ifdef HAVE_PTHREAD_TRYJOIN
+			/* A somewhat naive and brute-force solution for
+			 * systems without a semaphore.h. This may suffer
+			 * some off-by-one errors, using a few more threads
+			 * than intended (if we race a bit at the wrong time,
+			 * probably up to one per enabled scanner routine).
+			 */
+
+			/* TOTHINK: Should there be a threadcount_mutex when
+			 * we just read the value in if() and while() below?
+			 * At worst we would overflow the limit a bit due to
+			 * other protocol scanners...
+			 */
+			if (curr_threads >= max_threads
+			|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+			) {
+				upsdebugx(2, "%s: already running %" PRIuSIZE " scanning threads "
+					"(launched overall: %" PRIuSIZE "), "
+					"waiting until some would finish",
+					__func__, curr_threads, thread_count);
+
+				while (curr_threads >= max_threads
+				   || (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+				) {
+					for (i = 0; i < thread_count ; i++) {
+						int ret;
+
+						if (!thread_array[i].active) continue;
+
+						pthread_mutex_lock(&threadcount_mutex);
+						upsdebugx(3, "%s: Trying to join thread #%" PRIuSIZE "...", __func__, i);
+						ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
+						switch (ret) {
+							case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
+								upsdebugx(5, "%s: Was thread #%" PRIuSIZE " joined earlier?", __func__, i);
+								break;
+							case 0:         /* thread exited */
+								if (curr_threads > 0) {
+									curr_threads --;
+									upsdebugx(4, "%s: Joined a finished thread #%" PRIuSIZE, __func__, i);
+								} else {
+									/* threadcount_mutex fault? */
+									upsdebugx(0, "WARNING: %s: Accounting of thread count "
+										"says we are already at 0", __func__);
+								}
+								thread_array[i].active = FALSE;
+								break;
+							case EBUSY:     /* actively running */
+								upsdebugx(6, "%s: thread #%" PRIuSIZE " still busy (%i)",
+									__func__, i, ret);
+								break;
+							case EDEADLK:   /* Errors with thread interactions... bail out? */
+							case EINVAL:    /* Errors with thread interactions... bail out? */
+							default:        /* new pthreads abilities? */
+								upsdebugx(5, "%s: thread #%" PRIuSIZE " reported code %i",
+									__func__, i, ret);
+								break;
+						}
+						pthread_mutex_unlock(&threadcount_mutex);
+					}
+
+					if (curr_threads >= max_threads
+					|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+					) {
+							usleep (10000); /* microSec's, so 0.01s here */
+					}
+				}
+				upsdebugx(2, "%s: proceeding with scan", __func__);
+			}
 
-			if ((current_nut_dev = nutscan_scan_ipmi_device(ip_str, tmp_sec)) != NULL) {
-				/* Store the positive result */
-				current_nut_dev = nutscan_add_device_to_device(current_nut_dev, nut_dev);
+			/* NOTE: No change to default "pass" in this ifdef:
+			 * if we got to this line, we have a slot to use */
+#  endif /* HAVE_PTHREAD_TRYJOIN */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+#endif   /* HAVE_PTHREAD */
+
+			if (pass) {
+				tmp_sec = malloc(sizeof(nutscan_ipmi_t));
+				if (tmp_sec == NULL) {
+					upsdebugx(0, "%s: Memory allocation error", __func__);
+					break;
+				}
+
+				memcpy(tmp_sec, sec, sizeof(nutscan_ipmi_t));
+				tmp_sec->peername = ip_str;
+
+#ifdef HAVE_PTHREAD
+				if (pthread_create(&thread, NULL, nutscan_scan_ipmi_device_thready, (void*)tmp_sec) == 0) {
+					nutscan_thread_t	*new_thread_array;
+# ifdef HAVE_PTHREAD_TRYJOIN
+					pthread_mutex_lock(&threadcount_mutex);
+					curr_threads++;
+# endif /* HAVE_PTHREAD_TRYJOIN */
+
+					thread_count++;
+					new_thread_array = realloc(thread_array,
+						thread_count * sizeof(nutscan_thread_t));
+					if (new_thread_array == NULL) {
+						upsdebugx(1, "%s: Failed to realloc thread array", __func__);
+						break;
+					}
+					else {
+						thread_array = new_thread_array;
+					}
+					thread_array[thread_count - 1].thread = thread;
+					thread_array[thread_count - 1].active = TRUE;
+
+# ifdef HAVE_PTHREAD_TRYJOIN
+					pthread_mutex_unlock(&threadcount_mutex);
+# endif /* HAVE_PTHREAD_TRYJOIN */
+				}
+#else	/* if not HAVE_PTHREAD */
+				nutscan_scan_ipmi_device_thready(tmp_sec);
+#endif	/* if HAVE_PTHREAD */
+
+				/* Prepare the next iteration; note that
+				 * nutscan_scan_ipmi_device_thready()
+				 * takes care of freeing "tmp_sec" and its
+				 * reference (NOT strdup!) to "ip_str" as
+				 * peername.
+				 */
+				ip_str = nutscan_ip_ranges_iter_inc(&ip);
+			} else { /* if not pass -- all slots busy */
+#ifdef HAVE_PTHREAD
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+				/* Wait for all current scans to complete */
+				if (thread_array != NULL) {
+					upsdebugx (2, "%s: Running too many scanning threads (%"
+						PRIuSIZE "), "
+						"waiting until older ones would finish",
+						__func__, thread_count);
+					for (i = 0; i < thread_count ; i++) {
+						int ret;
+						if (!thread_array[i].active) {
+							/* Probably should not get here,
+							 * but handle it just in case */
+							upsdebugx(0, "WARNING: %s: Midway clean-up: did not expect thread %" PRIuSIZE " to be not active",
+								__func__, i);
+							sem_post(semaphore);
+							if (max_threads_scantype > 0)
+								sem_post(semaphore_scantype);
+							continue;
+						}
+						thread_array[i].active = FALSE;
+						ret = pthread_join(thread_array[i].thread, NULL);
+						if (ret != 0) {
+							upsdebugx(0, "WARNING: %s: Midway clean-up: pthread_join() returned code %i",
+								__func__, ret);
+						}
+						sem_post(semaphore);
+						if (max_threads_scantype > 0)
+							sem_post(semaphore_scantype);
+					}
+					thread_count = 0;
+					free(thread_array);
+					thread_array = NULL;
+				}
+# else
+#  ifdef HAVE_PTHREAD_TRYJOIN
+				/* TODO: Move the wait-loop for TRYJOIN here? */
+#  endif /* HAVE_PTHREAD_TRYJOIN */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+#endif   /* HAVE_PTHREAD */
+			} /* if: could we "pass" or not? */
+		} /* while */
+
+#ifdef HAVE_PTHREAD
+		if (thread_array != NULL) {
+			upsdebugx(2, "%s: all planned scans launched, waiting for threads to complete", __func__);
+			for (i = 0; i < thread_count; i++) {
+				int ret;
+
+				if (!thread_array[i].active) continue;
+
+				ret = pthread_join(thread_array[i].thread, NULL);
+				if (ret != 0) {
+					upsdebugx(0, "WARNING: %s: Clean-up: pthread_join() returned code %i",
+						__func__, ret);
+				}
+				thread_array[i].active = FALSE;
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+				sem_post(semaphore);
+				if (max_threads_scantype > 0)
+					sem_post(semaphore_scantype);
+# else
+#  ifdef HAVE_PTHREAD_TRYJOIN
+				pthread_mutex_lock(&threadcount_mutex);
+				if (curr_threads > 0) {
+					curr_threads --;
+					upsdebugx(5, "%s: Clean-up: Joined a finished thread #%" PRIuSIZE,
+						__func__, i);
+				} else {
+					upsdebugx(0, "WARNING: %s: Clean-up: Accounting of thread count "
+						"says we are already at 0", __func__);
+				}
+				pthread_mutex_unlock(&threadcount_mutex);
+#  endif /* HAVE_PTHREAD_TRYJOIN */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 			}
-			/* Prepare the next iteration */
-			ip_str = nutscan_ip_iter_inc(&ip);
+			free(thread_array);
+			upsdebugx(2, "%s: all threads freed", __func__);
 		}
-	}
+		pthread_mutex_destroy(&dev_mutex);
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		if (max_threads_scantype > 0) {
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+			sem_destroy(semaphore_scantype);
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+			if (semaphore_scantype) {
+				sem_unlink(SEMNAME_IPMI);
+				sem_close(semaphore_scantype);
+				semaphore_scantype = NULL;
+			}
+#  endif
+		}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+#endif /* HAVE_PTHREAD */
+	}	/* end of: scan range of 1+ IP address(es), maybe in parallel */
 
-	return nutscan_rewind_device(current_nut_dev);
+	result = nutscan_rewind_device(dev_ret);
+	dev_ret = NULL;
+	return result;
 }
 
 #else /* not WITH_IPMI */
@@ -646,4 +1089,17 @@ nutscan_device_t *  nutscan_scan_ipmi(const char * startIP, const char * stopIP,
 	return NULL;
 }
 
+/* stub function */
+nutscan_device_t *  nutscan_scan_ip_range_ipmi(nutscan_ip_range_list_t * irl, nutscan_ipmi_t * sec)
+{
+	NUT_UNUSED_VARIABLE(irl);
+	NUT_UNUSED_VARIABLE(sec);
+
+	return NULL;
+}
+
+int nutscan_unload_ipmi_library(void)
+{
+	return 0;
+}
 #endif /* WITH_IPMI */
diff --git a/tools/nut-scanner/scan_nut.c b/tools/nut-scanner/scan_nut.c
index cfff369f8e..76410785f5 100644
--- a/tools/nut-scanner/scan_nut.c
+++ b/tools/nut-scanner/scan_nut.c
@@ -2,6 +2,7 @@
  *  Copyright (C) 2011 - 2023 Arnaud Quette (Design and part of implementation)
  *  Copyright (C) 2011 - EATON
  *  Copyright (C) 2016-2021 - EATON - Various threads-related improvements
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -29,6 +30,10 @@
 #include "upsclient.h"
 #include "nut-scan.h"
 #include "nut_stdint.h"
+
+/* externally visible to nutscan-init */
+int nutscan_unload_upsclient_library(void);
+
 #include <ltdl.h>
 
 #define SCAN_NUT_DRIVERNAME "dummy-ups"
@@ -36,6 +41,7 @@
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
+static char *dl_saved_libname = NULL;
 
 static int (*nut_upscli_splitaddr)(const char *buf, char **hostname, uint16_t *port);
 static int (*nut_upscli_tryconnect)(UPSCONN_t *ups, const char *host, uint16_t port,
@@ -46,6 +52,8 @@ static int (*nut_upscli_list_next)(UPSCONN_t *ups, size_t numq,
 			const char **query, size_t *numa, char ***answer);
 static int (*nut_upscli_disconnect)(UPSCONN_t *ups);
 
+/* This variable collects device(s) from a sequential or parallel scan,
+ * is returned to caller, and cleared to allow subsequent independent scans */
 static nutscan_device_t * dev_ret = NULL;
 #ifdef HAVE_PTHREAD
 static pthread_mutex_t dev_mutex;
@@ -59,40 +67,52 @@ typedef int bool_t;
 #endif
 
 struct scan_nut_arg {
+	/* String includes square brackets around host/IP
+	 * address, and/or :port suffix (if customized so): */
 	char * hostname;
 	useconds_t timeout;
 };
 
-/* return 0 on error; visible externally */
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_upsclient_library(void)
+{
+	return nutscan_unload_library(&nutscan_avail_nut, &dl_handle, &dl_saved_libname);
+}
+
+/* Return 0 on error; visible externally */
 int nutscan_load_upsclient_library(const char *libname_path);
 int nutscan_load_upsclient_library(const char *libname_path)
 {
 	if (dl_handle != NULL) {
-			/* if previous init failed */
-			if (dl_handle == (void *)1) {
-					return 0;
-			}
-			/* init has already been done */
-			return 1;
+		/* if previous init failed */
+		if (dl_handle == (void *)1) {
+				return 0;
+		}
+		/* init has already been done */
+		return 1;
 	}
 
 	if (libname_path == NULL) {
-		fprintf(stderr, "NUT client library not found. NUT search disabled.\n");
+		upsdebugx(0, "NUT client library not found. NUT search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-			fprintf(stderr, "Error initializing lt_init\n");
-			return 0;
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
+		return 0;
 	}
 
 	dl_handle = lt_dlopen(libname_path);
 	if (!dl_handle) {
-			dl_error = lt_dlerror();
-			goto err;
+		dl_error = lt_dlerror();
+		goto err;
 	}
 
-	lt_dlerror();      /* Clear any existing error */
+	/* Clear any existing error */
+	lt_dlerror();
 
 	*(void **) (&nut_upscli_splitaddr) = lt_dlsym(dl_handle,
 						"upscli_splitaddr");
@@ -124,19 +144,32 @@ int nutscan_load_upsclient_library(const char *libname_path)
 			goto err;
 	}
 
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
+
 	return 1;
 
 err:
-	fprintf(stderr,
-		"Cannot load NUT library (%s) : %s. NUT search disabled.\n",
+	upsdebugx(0,
+		"Cannot load NUT library (%s) : %s. NUT search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 }
+/* end of dynamic link library stuff */
 
 /* FIXME: SSL support */
-static void * list_nut_devices(void * arg)
+/* Performs a (parallel-able) NUT protocol scan of one remote host:port.
+ * Returns NULL, updates global dev_ret when a scan is successful.
+ * FREES the caller's copy of "nut_arg" and "hostname" in it, if applicable.
+ */
+static void * list_nut_devices_thready(void * arg)
 {
 	struct scan_nut_arg * nut_arg = (struct scan_nut_arg*)arg;
 	char *target_hostname = nut_arg->hostname;
@@ -144,9 +177,9 @@ static void * list_nut_devices(void * arg)
 	uint16_t port;
 	size_t numq, numa;
 	const char *query[4];
-	char **answer;
+	char **answer = NULL;
 	char *hostname = NULL;
-	UPSCONN_t *ups = malloc(sizeof(*ups));
+	UPSCONN_t *ups = xcalloc(1, sizeof(*ups));
 	nutscan_device_t * dev = NULL;
 	size_t buf_size;
 
@@ -156,37 +189,40 @@ static void * list_nut_devices(void * arg)
 	query[0] = "UPS";
 	numq = 1;
 
+	upsdebugx(2, "Entering %s for %s", __func__, target_hostname);
+
 	if ((*nut_upscli_splitaddr)(target_hostname, &hostname, &port) != 0) {
-		free(target_hostname);
-		free(nut_arg);
-		free(ups);
-		return NULL;
+		/* Avoid disconnect from not connected ups */
+		if (ups) {
+			if (ups->host)
+				free(ups->host);
+			free(ups);
+		}
+		ups = NULL;
+		goto end;
 	}
 
 	if ((*nut_upscli_tryconnect)(ups, hostname, port, UPSCLI_CONN_TRYSSL, &tv) < 0) {
-		free(target_hostname);
-		free(nut_arg);
-		free(ups);
-		return NULL;
+		/* Avoid disconnect from not connected ups */
+		if (ups) {
+			if (ups->host)
+				free(ups->host);
+			free(ups);
+		}
+		ups = NULL;
+		goto end;
 	}
 
 	if ((*nut_upscli_list_start)(ups, numq, query) < 0) {
-		(*nut_upscli_disconnect)(ups);
-		free(target_hostname);
-		free(nut_arg);
-		free(ups);
-		return NULL;
+		goto end;
 	}
 
 	while ((*nut_upscli_list_next)(ups, numq, query, &numa, &answer) == 1) {
 		/* UPS <upsname> <description> */
 		if (numa < 3) {
-			(*nut_upscli_disconnect)(ups);
-			free(target_hostname);
-			free(nut_arg);
-			free(ups);
-			return NULL;
+			goto end;
 		}
+
 		/* FIXME: check for duplication by getting driver.port and device.serial
 		 * for comparison with other busses results */
 		/* FIXME:
@@ -197,8 +233,11 @@ static void * list_nut_devices(void * arg)
 		/* NOTE: There is no driver by such name, in practice it could
 		 * be a dummy-ups relay, a clone driver, or part of upsmon config */
 		dev->driver = strdup(SCAN_NUT_DRIVERNAME);
-		/* +1+1 is for '@' character and terminating 0 */
-		buf_size = strlen(answer[1]) + strlen(hostname) + 1 + 1;
+		/* +1+1 is for '@' character and terminating 0,
+		 * and the other +1+1 is for possible '[' and ']'
+		 * around the host name:
+		 */
+		buf_size = strlen(answer[1]) + strlen(hostname) + 1 + 1 + 1 + 1;
 		if (port != PORT) {
 			/* colon and up to 5 digits */
 			buf_size += 6;
@@ -207,13 +246,31 @@ static void * list_nut_devices(void * arg)
 		dev->port = malloc(buf_size);
 
 		if (dev->port) {
+			/* Check if IPv6 and needs brackets */
+			char	*hostname_colon = strchr(hostname, ':');
+
+			if (hostname_colon && *hostname_colon == '\0')
+				hostname_colon = NULL;
+			if (*hostname == '[')
+				hostname_colon = NULL;
+
 			if (port != PORT) {
-				snprintf(dev->port, buf_size, "%s@%s:%" PRIu16,
-					answer[1], hostname, port);
+				if (hostname_colon) {
+					snprintf(dev->port, buf_size, "%s@[%s]:%" PRIu16,
+						answer[1], hostname, port);
+				} else {
+					snprintf(dev->port, buf_size, "%s@%s:%" PRIu16,
+						answer[1], hostname, port);
+				}
 			} else {
 				/* Standard port, not suffixed */
-				snprintf(dev->port, buf_size, "%s@%s",
-					answer[1], hostname);
+				if (hostname_colon) {
+					snprintf(dev->port, buf_size, "%s@[%s]",
+						answer[1], hostname);
+				} else {
+					snprintf(dev->port, buf_size, "%s@%s",
+						answer[1], hostname);
+				}
 			}
 #ifdef HAVE_PTHREAD
 			pthread_mutex_lock(&dev_mutex);
@@ -226,17 +283,46 @@ static void * list_nut_devices(void * arg)
 
 	}
 
-	(*nut_upscli_disconnect)(ups);
-	free(target_hostname);
-	free(nut_arg);
-	free(ups);
+end:
+	if (ups) {
+		(*nut_upscli_disconnect)(ups);
+		if (ups->host)
+			free(ups->host);
+		free(ups);
+	}
+
+	if (target_hostname)
+		free(target_hostname);
+	if (hostname)
+		free(hostname);
+	if (nut_arg)
+		free(nut_arg);
+
 	return NULL;
 }
 
-nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, const char* port, useconds_t usec_timeout)
+nutscan_device_t * nutscan_scan_nut(const char* start_ip, const char* stop_ip, const char* port, useconds_t usec_timeout)
+{
+	nutscan_device_t	*ndret;
+	nutscan_ip_range_list_t irl;
+
+	nutscan_init_ip_ranges(&irl);
+	nutscan_add_ip_range(&irl, (char *)start_ip, (char *)stop_ip);
+
+	ndret = nutscan_scan_ip_range_nut(&irl, port, usec_timeout);
+
+	/* Avoid nuking caller's strings here */
+	irl.ip_ranges->start_ip = NULL;
+	irl.ip_ranges->end_ip = NULL;
+	nutscan_free_ip_ranges(&irl);
+
+	return ndret;
+}
+
+nutscan_device_t * nutscan_scan_ip_range_nut(nutscan_ip_range_list_t * irl, const char* port, useconds_t usec_timeout)
 {
 	bool_t pass = TRUE; /* Track that we may spawn a scanning thread */
-	nutscan_ip_iter_t ip;
+	nutscan_ip_range_list_iter_t ip;
 	char * ip_str = NULL;
 	char * ip_dest = NULL;
 	char buf[SMALLBUF];
@@ -245,28 +331,27 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 	int change_action_handler = 0;
 #endif
 	struct scan_nut_arg *nut_arg;
-#ifdef WIN32
-	WSADATA WSAdata;
-	WSAStartup(2,&WSAdata);
-	atexit((void(*)(void))WSACleanup);
-#endif
 
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	sem_t * semaphore = nutscan_semaphore();
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
 	sem_t   semaphore_scantype_inst;
 	sem_t * semaphore_scantype = &semaphore_scantype_inst;
-# endif /* HAVE_SEMAPHORE */
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+	sem_t * semaphore_scantype = NULL;
+#  endif
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 	pthread_t thread;
 	nutscan_thread_t * thread_array = NULL;
 	size_t thread_count = 0, i;
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	size_t  max_threads_scantype = max_threads_oldnut;
 # endif
 
 	pthread_mutex_init(&dev_mutex, NULL);
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	if (max_threads_scantype > 0) {
 #ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
 #pragma GCC diagnostic push
@@ -287,13 +372,26 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 #pragma GCC diagnostic pop
 #endif
 			upsdebugx(1,
-				"WARNING: %s: Limiting max_threads_scantype to range acceptable for sem_init()",
+				"WARNING: %s: Limiting max_threads_scantype to range acceptable for " REPORT_SEM_INIT_METHOD "()",
 				__func__);
 			max_threads_scantype = UINT_MAX - 1;
 		}
-		sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype);
+
+		upsdebugx(4, "%s: " REPORT_SEM_INIT_METHOD "() for %" PRIuSIZE " threads", __func__, max_threads_scantype);
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+		if (sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype)) {
+			upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+			max_threads_scantype = 0;
+		}
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		if (SEM_FAILED == (semaphore_scantype = sem_open(SEMNAME_UPSCLIENT, O_CREAT, 0644, (unsigned int)max_threads_scantype))) {
+			upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+			semaphore_scantype = NULL;
+			max_threads_scantype = 0;
+		}
+#  endif
 	}
-# endif /* HAVE_SEMAPHORE */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 
 #endif /* HAVE_PTHREAD */
 
@@ -301,6 +399,23 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 		return NULL;
 	}
 
+	if (irl == NULL || irl->ip_ranges == NULL) {
+		return NULL;
+	}
+
+	if (!irl->ip_ranges->start_ip) {
+		upsdebugx(1, "%s: no starting IP address specified", __func__);
+	} else if (irl->ip_ranges_count == 1
+		&& (irl->ip_ranges->start_ip == irl->ip_ranges->end_ip
+		    || !strcmp(irl->ip_ranges->start_ip, irl->ip_ranges->end_ip)
+	)) {
+		upsdebugx(1, "%s: Scanning \"Old NUT\" bus for single IP address: %s",
+			__func__, irl->ip_ranges->start_ip);
+	} else {
+		upsdebugx(1, "%s: Scanning \"Old NUT\" bus for IP address range(s): %s",
+			__func__, nutscan_stringify_ip_ranges(irl));
+	}
+
 #ifndef WIN32
 	/* Ignore SIGPIPE if the caller hasn't set a handler for it yet */
 	if (sigaction(SIGPIPE, NULL, &oldact) == 0) {
@@ -318,7 +433,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 	}
 #endif
 
-	ip_str = nutscan_ip_iter_init(&ip, startIP, stopIP);
+	ip_str = nutscan_ip_ranges_iter_init(&ip, irl);
 
 	while (ip_str != NULL) {
 #ifdef HAVE_PTHREAD
@@ -329,7 +444,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 		 * for below in pthread_join()...
 		 */
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 		/* Just wait for someone to free a semaphored slot,
 		 * if none are available, and then/otherwise grab one
 		 */
@@ -341,8 +456,22 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			sem_wait(semaphore);
 			pass = TRUE;
 		} else {
-			pass = ((max_threads_scantype == 0 || sem_trywait(semaphore_scantype) == 0) &&
-			        sem_trywait(semaphore) == 0);
+			/* If successful (the lock was acquired),
+			 * sem_wait() and sem_trywait() will return 0.
+			 * Otherwise, -1 is returned and errno is set,
+			 * and the state of the semaphore is unchanged.
+			 */
+			int	stwST = sem_trywait(semaphore_scantype);
+			int	stwS  = sem_trywait(semaphore);
+			pass = ((max_threads_scantype == 0 || stwST == 0) && stwS == 0);
+			upsdebugx(4, "%s: max_threads_scantype=%" PRIuSIZE
+				" curr_threads=%" PRIuSIZE
+				" thread_count=%" PRIuSIZE
+				" stwST=%d stwS=%d pass=%d",
+				__func__, max_threads_scantype,
+				curr_threads, thread_count,
+				stwST, stwS, pass
+			);
 		}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
@@ -365,6 +494,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 				"(launched overall: %" PRIuSIZE "), "
 				"waiting until some would finish",
 				__func__, curr_threads, thread_count);
+
 			while (curr_threads >= max_threads
 			   || (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
 			) {
@@ -374,7 +504,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 					if (!thread_array[i].active) continue;
 
 					pthread_mutex_lock(&threadcount_mutex);
-					upsdebugx(3, "%s: Trying to join thread #%i...", __func__, i);
+					upsdebugx(3, "%s: Trying to join thread #%" PRIuSIZE "...", __func__, i);
 					ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
 					switch (ret) {
 						case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
@@ -413,15 +543,16 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			}
 			upsdebugx(2, "%s: proceeding with scan", __func__);
 		}
+
 		/* NOTE: No change to default "pass" in this ifdef:
 		 * if we got to this line, we have a slot to use */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 
 		if (pass) {
 			if (port) {
-				if (ip.type == IPv4) {
+				if (ip.curr_ip_iter.type == IPv4) {
 					snprintf(buf, sizeof(buf), "%s:%s", ip_str, port);
 				}
 				else {
@@ -435,6 +566,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			}
 
 			if ((nut_arg = malloc(sizeof(struct scan_nut_arg))) == NULL) {
+				upsdebugx(0, "%s: Memory allocation error", __func__);
 				free(ip_dest);
 				break;
 			}
@@ -443,7 +575,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			nut_arg->hostname = ip_dest;
 
 #ifdef HAVE_PTHREAD
-			if (pthread_create(&thread, NULL, list_nut_devices, (void*)nut_arg) == 0) {
+			if (pthread_create(&thread, NULL, list_nut_devices_thready, (void*)nut_arg) == 0) {
 				nutscan_thread_t	*new_thread_array;
 # ifdef HAVE_PTHREAD_TRYJOIN
 				pthread_mutex_lock(&threadcount_mutex);
@@ -467,19 +599,27 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 				pthread_mutex_unlock(&threadcount_mutex);
 # endif /* HAVE_PTHREAD_TRYJOIN */
 			}
-#else  /* not HAVE_PTHREAD */
-			list_nut_devices(nut_arg);
+#else  /* if not HAVE_PTHREAD */
+			list_nut_devices_thready(nut_arg);
 #endif /* if HAVE_PTHREAD */
+
+			/* Prepare the next iteration; note that
+			 * nutscan_scan_ipmi_device_thready()
+			 * takes care of freeing "tmp_sec" and its
+			 * copy (note strdup!) of "ip_str" as
+			 * hostname, possibly suffixed with a port.
+			 */
 			free(ip_str);
-			ip_str = nutscan_ip_iter_inc(&ip);
+			ip_str = nutscan_ip_ranges_iter_inc(&ip);
 		} else { /* if not pass -- all slots busy */
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			/* Wait for all current scans to complete */
 			if (thread_array != NULL) {
-				upsdebugx (2, "%s: Running too many scanning threads, "
+				upsdebugx (2, "%s: Running too many scanning threads (%"
+					PRIuSIZE "), "
 					"waiting until older ones would finish",
-					__func__);
+					__func__, thread_count);
 				for (i = 0; i < thread_count ; i++) {
 					int ret;
 					if (!thread_array[i].active) {
@@ -508,9 +648,9 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
-		/* TODO: Move the wait-loop for TRYJOIN here? */
+			/* TODO: Move the wait-loop for TRYJOIN here? */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 		} /* if: could we "pass" or not? */
 	} /* while */
@@ -529,7 +669,7 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 					__func__, ret);
 			}
 			thread_array[i].active = FALSE;
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			sem_post(semaphore);
 			if (max_threads_scantype > 0)
 				sem_post(semaphore_scantype);
@@ -546,17 +686,26 @@ nutscan_device_t * nutscan_scan_nut(const char* startIP, const char* stopIP, con
 			}
 			pthread_mutex_unlock(&threadcount_mutex);
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif /* HAVE_SEMAPHORE */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 		}
 		free(thread_array);
 		upsdebugx(2, "%s: all threads freed", __func__);
 	}
 	pthread_mutex_destroy(&dev_mutex);
 
-# ifdef HAVE_SEMAPHORE
-	if (max_threads_scantype > 0)
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+	if (max_threads_scantype > 0) {
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
 		sem_destroy(semaphore_scantype);
-# endif /* HAVE_SEMAPHORE */
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		if (semaphore_scantype) {
+			sem_unlink(SEMNAME_UPSCLIENT);
+			sem_close(semaphore_scantype);
+			semaphore_scantype = NULL;
+		}
+#  endif
+	}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif /* HAVE_PTHREAD */
 
 #ifndef WIN32
diff --git a/tools/nut-scanner/scan_nut_simulation.c b/tools/nut-scanner/scan_nut_simulation.c
index 402293ad47..7324ddb1d8 100644
--- a/tools/nut-scanner/scan_nut_simulation.c
+++ b/tools/nut-scanner/scan_nut_simulation.c
@@ -45,10 +45,13 @@ nutscan_device_t * nutscan_scan_nut_simulation(void)
 	pthread_mutex_init(&dev_mutex, NULL);
 #endif /* HAVE_PTHREAD */
 
-	upsdebugx(1,"Scanning: %s", CONFPATH);
+	upsdebugx(1, "Scanning: %s", CONFPATH);
 
 	if ((dp = opendir(CONFPATH)) == NULL) {
-		fatal_with_errno(EXIT_FAILURE, "Failed to open %s", CONFPATH);
+		upsdebug_with_errno(1, "%s: Failed to open %s",
+			__func__, CONFPATH);
+		upsdebugx(0, "Failed to open %s, skip NUT simulation scan",
+			CONFPATH);
 		return NULL;
 	}
 
@@ -63,7 +66,7 @@ nutscan_device_t * nutscan_scan_nut_simulation(void)
 
 		/* Filter on '.dev' and '.seq' extensions' */
 		if ((strcmp(ext, ".dev") == 0) || (strcmp(ext, ".seq") == 0)) {
-			upsdebugx(1,"Found simulation file: %s", dirp->d_name);
+			upsdebugx(1, "Found simulation file: %s", dirp->d_name);
 
 			dev = nutscan_new_device();
 			dev->type = TYPE_NUT_SIMULATION;
diff --git a/tools/nut-scanner/scan_snmp.c b/tools/nut-scanner/scan_snmp.c
index 8a28b8e9b1..a8c3b42cb3 100644
--- a/tools/nut-scanner/scan_snmp.c
+++ b/tools/nut-scanner/scan_snmp.c
@@ -1,6 +1,7 @@
 /*
  *  Copyright (C) 2011 - EATON
  *  Copyright (C) 2016-2021 - EATON - Various threads-related improvements
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -20,6 +21,7 @@
 /*! \file scan_snmp.c
     \brief detect NUT supported SNMP devices
     \author Frederic Bohe <FredericBohe@Eaton.com>
+    \author Jim Klimov <EvgenyKlimov@Eaton.com>
     \author Arnaud Quette <ArnaudQuette@Eaton.com>
     \author Jim Klimov <EvgenyKlimov@eaton.com>
 */
@@ -28,55 +30,89 @@
 #include "nut-scan.h"
 #include "nut_stdint.h"
 
+/* externally visible to nutscan-init */
+int nutscan_unload_snmp_library(void);
+
 #ifdef WITH_SNMP
 
 #ifndef WIN32
-#include <sys/socket.h>
+# include <sys/socket.h>
 #else
-#undef _WIN32_WINNT
+# undef _WIN32_WINNT
 #endif
 
-#include <stdio.h>
 #include <string.h>
+#include <stdio.h>
 #include <ltdl.h>
 
 /* workaround for buggy Net-SNMP config
  * from drivers/snmp-ups.h */
 #ifdef PACKAGE_BUGREPORT
-#undef PACKAGE_BUGREPORT
+# undef PACKAGE_BUGREPORT
 #endif
 
 #ifdef PACKAGE_NAME
-#undef PACKAGE_NAME
+# undef PACKAGE_NAME
 #endif
 
 #ifdef PACKAGE_VERSION
-#undef PACKAGE_VERSION
+# undef PACKAGE_VERSION
 #endif
 
 #ifdef PACKAGE_STRING
-#undef PACKAGE_STRING
+# undef PACKAGE_STRING
 #endif
 
 #ifdef PACKAGE_TARNAME
-#undef PACKAGE_TARNAME
+# undef PACKAGE_TARNAME
 #endif
 
+#ifdef PACKAGE_URL
+# undef PACKAGE_URL
+#endif
+
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_PARAMETER)
+# pragma GCC diagnostic push
+# pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+#ifdef __clang__
+# pragma clang diagnostic push
+# pragma clang diagnostic ignored "-Wunused-parameter"
+#endif
+/* These tend to have inlined API implementations as empty braces,
+ * causing warnings about unused parameters.
+ */
 #include <net-snmp/net-snmp-config.h>
 #include <net-snmp/net-snmp-includes.h>
+
+#ifdef __clang__
+# pragma clang diagnostic pop
+#endif
+#if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNUSED_PARAMETER)
+# pragma GCC diagnostic pop
+#endif
+
 #include "nutscan-snmp.h"
 
 /* Address API change */
 #if ( ! NUT_HAVE_LIBNETSNMP_usmAESPrivProtocol ) && ( ! defined usmAESPrivProtocol )
-#define USMAESPRIVPROTOCOL "usmAES128PrivProtocol"
-#define USMAESPRIVPROTOCOL_PTR usmAES128PrivProtocol
+# define USMAESPRIVPROTOCOL "usmAES128PrivProtocol"
+# define USMAESPRIVPROTOCOL_PTR usmAES128PrivProtocol
 #else
-#define USMAESPRIVPROTOCOL "usmAESPrivProtocol"
-#define USMAESPRIVPROTOCOL_PTR usmAESPrivProtocol
+# define USMAESPRIVPROTOCOL "usmAESPrivProtocol"
+# define USMAESPRIVPROTOCOL_PTR usmAESPrivProtocol
 #endif
 
 #define SysOID ".1.3.6.1.2.1.1.2.0"
 
+/* This variable collects device(s) from a sequential or parallel scan,
+ * is returned to caller, and cleared to allow subsequent independent scans */
+static nutscan_device_t * dev_ret = NULL;
+#ifdef HAVE_PTHREAD
+static pthread_mutex_t dev_mutex;
+#endif
+static useconds_t g_usec_timeout ;
+
 /* use explicit booleans */
 #ifndef FALSE
 typedef enum ebool { FALSE = 0, TRUE } bool_t;
@@ -84,17 +120,13 @@ typedef enum ebool { FALSE = 0, TRUE } bool_t;
 typedef int bool_t;
 #endif
 
-static nutscan_device_t * dev_ret = NULL;
-#ifdef HAVE_PTHREAD
-static pthread_mutex_t dev_mutex;
-#endif
-static useconds_t g_usec_timeout ;
-
 #ifndef WITH_SNMP_STATIC
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
-#endif
+static char *dl_saved_libname = NULL;
+#endif	/* WITH_SNMP_STATIC */
+static int nut_initialized_snmp = 0;
 
 static void (*nut_init_snmp)(const char *type);
 static void (*nut_snmp_sess_init)(netsnmp_session * session);
@@ -155,9 +187,24 @@ static oid *nut_usmHMAC256SHA384AuthProtocol;
 static oid *nut_usmHMAC384SHA512AuthProtocol;
 #endif
 
-/* return 0 on error; visible externally */
-int nutscan_load_snmp_library(const char *libname_path);
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+#ifndef WITH_SNMP_STATIC
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+#endif
+int nutscan_unload_snmp_library(void)
+{
+#ifdef WITH_SNMP_STATIC
+	return 0;
+#else
+	nut_initialized_snmp = 0;
+	return nutscan_unload_library(&nutscan_avail_snmp, &dl_handle, &dl_saved_libname);
+#endif
+}
 
+/* Return 0 on error; visible externally */
+int nutscan_load_snmp_library(const char *libname_path);
 int nutscan_load_snmp_library(const char *libname_path)
 {
 #ifdef WITH_SNMP_STATIC
@@ -255,12 +302,12 @@ int nutscan_load_snmp_library(const char *libname_path)
 	}
 
 	if (libname_path == NULL) {
-		upsdebugx(1, "SNMP library not found. SNMP search disabled");
+		upsdebugx(0, "SNMP library not found. SNMP search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-		upsdebugx(1, "Error initializing lt_init");
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
 		return 0;
 	}
 
@@ -270,7 +317,9 @@ int nutscan_load_snmp_library(const char *libname_path)
 		goto err;
 	}
 
-	lt_dlerror();	/* Clear any existing error */
+	/* Clear any existing error */
+	lt_dlerror();
+
 	*(void **) (&nut_init_snmp) = lt_dlsym(dl_handle, "init_snmp");
 	if ((dl_error = lt_dlerror()) != NULL) {
 		goto err;
@@ -431,17 +480,25 @@ int nutscan_load_snmp_library(const char *libname_path)
 	}
 #endif /* NUT_HAVE_LIBNETSNMP_usmHMAC384SHA512AuthProtocol */
 
-#endif	/* WITH_SNMP_STATIC */
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
+
+#endif	/* not WITH_SNMP_STATIC */
 
 	return 1;
 
 #ifndef WITH_SNMP_STATIC
 err:
-	fprintf(stderr,
-		"Cannot load SNMP library (%s) : %s. SNMP search disabled.\n",
+	upsdebugx(0,
+		"Cannot load SNMP library (%s) : %s. SNMP search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 #endif	/* not WITH_SNMP_STATIC */
 }
@@ -461,6 +518,8 @@ static void scan_snmp_add_device(nutscan_snmp_t * sec, struct snmp_pdu *response
 	dev = nutscan_new_device();
 	dev->type = TYPE_SNMP;
 	dev->driver = strdup("snmp-ups");
+	/* FIXME: Should the IPv6 address here be bracketed?
+	 *  Does our driver support the notation? */
 	dev->port = strdup(session->peername);
 	if (response != NULL) {
 		buf = malloc (response->variables->val_len + 1);
@@ -639,15 +698,16 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 		else if (strcmp(sec->secLevel, "authPriv") == 0)
 			snmp_sess->securityLevel = SNMP_SEC_LEVEL_AUTHPRIV;
 		else {
-			fprintf(stderr,
-				"Bad SNMPv3 securityLevel: %s\n",
-				sec->secLevel);
+			upsdebugx(0, "WARNING: %s: "
+				"Bad SNMPv3 securityLevel: %s",
+				__func__, sec->secLevel);
 			return 0;
 		}
 
 		/* Security name */
 		if (sec->secName == NULL) {
-			fprintf(stderr, "securityName is required for SNMPv3\n");
+			upsdebugx(0, "WARNING: %s: securityName is required for SNMPv3",
+				__func__);
 			return 0;
 		}
 		snmp_sess->securityName = strdup(sec->secName);
@@ -662,20 +722,20 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 		switch (snmp_sess->securityLevel) {
 			case SNMP_SEC_LEVEL_AUTHNOPRIV:
 				if (sec->authPassword == NULL) {
-					fprintf(stderr,
+					upsdebugx(0, "WARNING: %s: "
 						"authPassword is required "
-						"for SNMPv3 in %s mode\n",
-						sec->secLevel);
+						"for SNMPv3 in %s mode",
+						__func__, sec->secLevel);
 					return 0;
 				}
 				break;
 			case SNMP_SEC_LEVEL_AUTHPRIV:
 				if ((sec->authPassword == NULL) ||
 					(sec->privPassword == NULL)) {
-					fprintf(stderr,
+					upsdebugx(0, "WARNING: %s: "
 						"authPassword and privPassword are "
-						"required for SNMPv3 in %s mode\n",
-						sec->secLevel);
+						"required for SNMPv3 in %s mode",
+						__func__, sec->secLevel);
 					return 0;
 				}
 				break;
@@ -737,9 +797,9 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 #else
 			{
 #endif
-				fprintf(stderr,
-					"Bad SNMPv3 authProtocol: %s\n",
-					sec->authProtocol);
+				upsdebugx(0, "WARNING: %s: "
+					"Bad SNMPv3 authProtocol: %s",
+					__func__, sec->authProtocol);
 				return 0;
 			}
 		}
@@ -759,8 +819,8 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 #if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) )
 # pragma GCC diagnostic pop
 #endif
-			fprintf(stderr, "Bad SNMPv3 securityAuthProtoLen: %" PRIuSIZE,
-				snmp_sess->securityAuthProtoLen);
+			upsdebugx(0, "WARNING: %s: Bad SNMPv3 securityAuthProtoLen: %" PRIuSIZE,
+				__func__, snmp_sess->securityAuthProtoLen);
 			return 0;
 		}
 		if ((*nut_generate_Ku)(snmp_sess->securityAuthProto,
@@ -771,9 +831,10 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 					&snmp_sess->securityAuthKeyLen)
 					!= SNMPERR_SUCCESS
 		) {
-			fprintf(stderr,
+			upsdebugx(0, "WARNING: %s: "
 				"Error generating Ku from "
-				"authentication pass phrase\n");
+				"authentication pass phrase",
+				__func__);
 			return 0;
 		}
 
@@ -824,9 +885,9 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 #else
 			{
 #endif
-				fprintf(stderr,
-					"Bad SNMPv3 privProtocol: %s\n",
-					sec->privProtocol);
+				upsdebugx(0, "WARNING: %s: "
+					"Bad SNMPv3 privProtocol: %s",
+					__func__, sec->privProtocol);
 				return 0;
 			}
 		}
@@ -847,8 +908,8 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 #if (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_PUSH_POP) && ( (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TYPE_LIMITS) || (defined HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_TAUTOLOGICAL_CONSTANT_OUT_OF_RANGE_COMPARE) )
 # pragma GCC diagnostic pop
 #endif
-			fprintf(stderr, "Bad SNMPv3 securityAuthProtoLen: %" PRIuSIZE,
-				snmp_sess->securityAuthProtoLen);
+			upsdebugx(0, "WARNING: %s: Bad SNMPv3 securityAuthProtoLen: %" PRIuSIZE,
+				__func__, snmp_sess->securityAuthProtoLen);
 			return 0;
 		}
 		if ((*nut_generate_Ku)(snmp_sess->securityAuthProto,
@@ -859,9 +920,10 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 					&snmp_sess->securityPrivKeyLen)
 					!= SNMPERR_SUCCESS
 		) {
-			fprintf(stderr,
+			upsdebugx(0, "WARNING: %s: "
 				"Error generating Ku from "
-				"private pass phrase\n");
+				"private pass phrase",
+				__func__);
 			return 0;
 		}
 
@@ -870,7 +932,17 @@ static int init_session(struct snmp_session * snmp_sess, nutscan_snmp_t * sec)
 	return 1;
 }
 
-static void * try_SysOID(void * arg)
+static void * wrap_nut_snmp_sess_open(struct snmp_session *session)
+{
+	/* Open the session */
+	return (*nut_snmp_sess_open)(session); /* establish the session */
+}
+
+/* Performs a (parallel-able) SNMP protocol scan of one remote host.
+ * Returns NULL, updates global dev_ret when a scan is successful.
+ * FREES the caller's copy of "sec" and "peername" in it, if applicable.
+ */
+static void * try_SysOID_thready(void * arg)
 {
 	struct snmp_session snmp_sess;
 	void * handle;
@@ -895,7 +967,7 @@ static void * try_SysOID(void * arg)
 	snmp_sess.timeout = (long)g_usec_timeout;
 
 	/* Open the session */
-	handle = (*nut_snmp_sess_open)(&snmp_sess); /* establish the session */
+	handle = wrap_nut_snmp_sess_open(&snmp_sess); /* establish the session */
 	if (handle == NULL) {
 		upsdebugx(2,
 			"Failed to open SNMP session for %s",
@@ -916,7 +988,7 @@ static void * try_SysOID(void * arg)
 	pdu = (*nut_snmp_pdu_create)(SNMP_MSG_GET);
 
 	if (pdu == NULL) {
-		fprintf(stderr, "Not enough memory\n");
+		upsdebugx(0, "%s: Memory allocation error", __func__);
 		(*nut_snmp_sess_close)(handle);
 		goto try_SysOID_free;
 	}
@@ -1001,47 +1073,103 @@ static void * try_SysOID(void * arg)
 	return NULL;
 }
 
+static void init_snmp_once(void)
+{
+	/* Initialize the SNMP library */
+	if (!nut_initialized_snmp) {
+		(*nut_init_snmp)("nut-scanner");
+		nut_initialized_snmp = 1;
+	}
+}
+
 nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip,
                                      useconds_t usec_timeout, nutscan_snmp_t * sec)
+{
+	nutscan_device_t	*ndret;
+	nutscan_ip_range_list_t irl;
+
+	nutscan_init_ip_ranges(&irl);
+	nutscan_add_ip_range(&irl, (char *)start_ip, (char *)stop_ip);
+
+	ndret = nutscan_scan_ip_range_snmp(&irl, usec_timeout, sec);
+
+	/* Avoid nuking caller's strings here */
+	irl.ip_ranges->start_ip = NULL;
+	irl.ip_ranges->end_ip = NULL;
+	nutscan_free_ip_ranges(&irl);
+
+	return ndret;
+}
+
+nutscan_device_t * nutscan_scan_ip_range_snmp(nutscan_ip_range_list_t * irl,
+                                     useconds_t usec_timeout, nutscan_snmp_t * sec)
 {
 	bool_t pass = TRUE; /* Track that we may spawn a scanning thread */
 	nutscan_device_t * result;
 	nutscan_snmp_t * tmp_sec;
-	nutscan_ip_iter_t ip;
+	nutscan_ip_range_list_iter_t ip;
 	char * ip_str = NULL;
+
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	sem_t * semaphore = nutscan_semaphore();
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
 	sem_t   semaphore_scantype_inst;
 	sem_t * semaphore_scantype = &semaphore_scantype_inst;
-# endif /* HAVE_SEMAPHORE */
-
-# ifdef WIN32
-	WSADATA WSAdata;
-	WSAStartup(2,&WSAdata);
-	atexit((void(*)(void))WSACleanup);
-# endif
-
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+	sem_t * semaphore_scantype = NULL;
+#  endif
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 	pthread_t thread;
 	nutscan_thread_t * thread_array = NULL;
 	size_t thread_count = 0, i;
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	size_t  max_threads_scantype = max_threads_netsnmp;
 # endif
 
 	pthread_mutex_init(&dev_mutex, NULL);
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 	if (max_threads_scantype > 0) {
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+		/* Different platforms, different sizes, none fits all... */
 		if (SIZE_MAX > UINT_MAX && max_threads_scantype > UINT_MAX) {
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
 			upsdebugx(1,
-				"WARNING: %s: Limiting max_threads_scantype to range acceptable for sem_init()",
+				"WARNING: %s: Limiting max_threads_scantype to range acceptable for " REPORT_SEM_INIT_METHOD "()",
 				__func__);
 			max_threads_scantype = UINT_MAX - 1;
 		}
-		sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype);
+
+		upsdebugx(4, "%s: " REPORT_SEM_INIT_METHOD "() for %" PRIuSIZE " threads", __func__, max_threads_scantype);
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+		if (sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype)) {
+			upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+			max_threads_scantype = 0;
+		}
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		if (SEM_FAILED == (semaphore_scantype = sem_open(SEMNAME_SNMP, O_CREAT, 0644, (unsigned int)max_threads_scantype))) {
+			upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+			semaphore_scantype = NULL;
+			max_threads_scantype = 0;
+		}
+#  endif
 	}
-# endif /* HAVE_SEMAPHORE */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 
 #endif /* HAVE_PTHREAD */
 
@@ -1049,18 +1177,35 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 		return NULL;
 	}
 
+	if (irl == NULL || irl->ip_ranges == NULL) {
+		return NULL;
+	}
+
+	if (!irl->ip_ranges->start_ip) {
+		upsdebugx(1, "%s: no starting IP address specified", __func__);
+	} else if (irl->ip_ranges_count == 1
+		&& (irl->ip_ranges->start_ip == irl->ip_ranges->end_ip
+		    || !strcmp(irl->ip_ranges->start_ip, irl->ip_ranges->end_ip)
+	)) {
+		upsdebugx(1, "%s: Scanning SNMP for single IP address: %s",
+			__func__, irl->ip_ranges->start_ip);
+	} else {
+		upsdebugx(1, "%s: Scanning SNMP for IP address range(s): %s",
+			__func__, nutscan_stringify_ip_ranges(irl));
+	}
+
 	g_usec_timeout = usec_timeout;
 
-	/* Force numeric OIDs resolution (ie, do not resolve to textual names)
+	/* Force numeric OIDs resolution (i.e., do not resolve to textual names)
 	 * This is mostly for the convenience of debug output */
 	if (nut_snmp_out_toggle_options("n") != NULL) {
 		upsdebugx(1, "Failed to enable numeric OIDs resolution");
 	}
 
 	/* Initialize the SNMP library */
-	(*nut_init_snmp)("nut-scanner");
+	init_snmp_once();
 
-	ip_str = nutscan_ip_iter_init(&ip, start_ip, stop_ip);
+	ip_str = nutscan_ip_ranges_iter_init(&ip, irl);
 
 	while (ip_str != NULL) {
 #ifdef HAVE_PTHREAD
@@ -1071,7 +1216,7 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 		 * for below in pthread_join()...
 		 */
 
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 		/* Just wait for someone to free a semaphored slot,
 		 * if none are available, and then/otherwise grab one
 		 */
@@ -1083,8 +1228,22 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 			sem_wait(semaphore);
 			pass = TRUE;
 		} else {
-			pass = ((max_threads_scantype == 0 || sem_trywait(semaphore_scantype) == 0) &&
-			        sem_trywait(semaphore) == 0);
+			/* If successful (the lock was acquired),
+			 * sem_wait() and sem_trywait() will return 0.
+			 * Otherwise, -1 is returned and errno is set,
+			 * and the state of the semaphore is unchanged.
+			 */
+			int	stwST = sem_trywait(semaphore_scantype);
+			int	stwS  = sem_trywait(semaphore);
+			pass = ((max_threads_scantype == 0 || stwST == 0) && stwS == 0);
+			upsdebugx(4, "%s: max_threads_scantype=%" PRIuSIZE
+				" curr_threads=%" PRIuSIZE
+				" thread_count=%" PRIuSIZE
+				" stwST=%d stwS=%d pass=%d",
+				__func__, max_threads_scantype,
+				curr_threads, thread_count,
+				stwST, stwS, pass
+			);
 		}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
@@ -1107,6 +1266,7 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 				"(launched overall: %" PRIuSIZE "), "
 				"waiting until some would finish",
 				__func__, curr_threads, thread_count);
+
 			while (curr_threads >= max_threads
 			   || (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
 			) {
@@ -1116,7 +1276,7 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 					if (!thread_array[i].active) continue;
 
 					pthread_mutex_lock(&threadcount_mutex);
-					upsdebugx(3, "%s: Trying to join thread #%i...", __func__, i);
+					upsdebugx(3, "%s: Trying to join thread #%" PRIuSIZE "...", __func__, i);
 					ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
 					switch (ret) {
 						case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
@@ -1155,19 +1315,25 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 			}
 			upsdebugx(2, "%s: proceeding with scan", __func__);
 		}
+
 		/* NOTE: No change to default "pass" in this ifdef:
 		 * if we got to this line, we have a slot to use */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 
 		if (pass) {
 			tmp_sec = malloc(sizeof(nutscan_snmp_t));
+			if (tmp_sec == NULL) {
+				upsdebugx(0, "%s: Memory allocation error", __func__);
+				break;
+			}
+
 			memcpy(tmp_sec, sec, sizeof(nutscan_snmp_t));
 			tmp_sec->peername = ip_str;
 
 #ifdef HAVE_PTHREAD
-			if (pthread_create(&thread, NULL, try_SysOID, (void*)tmp_sec) == 0) {
+			if (pthread_create(&thread, NULL, try_SysOID_thready, (void*)tmp_sec) == 0) {
 				nutscan_thread_t	*new_thread_array;
 # ifdef HAVE_PTHREAD_TRYJOIN
 				pthread_mutex_lock(&threadcount_mutex);
@@ -1191,20 +1357,26 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 				pthread_mutex_unlock(&threadcount_mutex);
 # endif /* HAVE_PTHREAD_TRYJOIN */
 			}
-#else   /* not HAVE_PTHREAD */
-			try_SysOID((void *)tmp_sec);
+#else   /* if not HAVE_PTHREAD */
+			try_SysOID_thready(tmp_sec);
 #endif  /* if HAVE_PTHREAD */
-/*			free(ip_str); */ /* Do not free() here - seems to cause a double-free instead */
-			ip_str = nutscan_ip_iter_inc(&ip);
-/*			free(tmp_sec); */
+
+			/* Prepare the next iteration; note that
+			 * try_SysOID_thready()
+			 * takes care of freeing "tmp_sec" and its
+			 * reference (NOT strdup!) to "ip_str" as
+			 * peername.
+			 */
+			ip_str = nutscan_ip_ranges_iter_inc(&ip);
 		} else { /* if not pass -- all slots busy */
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			/* Wait for all current scans to complete */
 			if (thread_array != NULL) {
-				upsdebugx (2, "%s: Running too many scanning threads, "
+				upsdebugx (2, "%s: Running too many scanning threads (%"
+					PRIuSIZE "), "
 					"waiting until older ones would finish",
-					__func__);
+					__func__, thread_count);
 				for (i = 0; i < thread_count ; i++) {
 					int ret;
 					if (!thread_array[i].active) {
@@ -1233,9 +1405,9 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 			}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
-		/* TODO: Move the wait-loop for TRYJOIN here? */
+			/* TODO: Move the wait-loop for TRYJOIN here? */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 		} /* if: could we "pass" or not? */
 	} /* while */
@@ -1254,7 +1426,7 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 					__func__, ret);
 			}
 			thread_array[i].active = FALSE;
-# ifdef HAVE_SEMAPHORE
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
 			sem_post(semaphore);
 			if (max_threads_scantype > 0)
 				sem_post(semaphore_scantype);
@@ -1271,17 +1443,26 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 			}
 			pthread_mutex_unlock(&threadcount_mutex);
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif /* HAVE_SEMAPHORE */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 		}
 		free(thread_array);
 		upsdebugx(2, "%s: all threads freed", __func__);
 	}
 	pthread_mutex_destroy(&dev_mutex);
 
-# ifdef HAVE_SEMAPHORE
-	if (max_threads_scantype > 0)
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+	if (max_threads_scantype > 0) {
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
 		sem_destroy(semaphore_scantype);
-# endif /* HAVE_SEMAPHORE */
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		if (semaphore_scantype) {
+			sem_unlink(SEMNAME_SNMP);
+			sem_close(semaphore_scantype);
+			semaphore_scantype = NULL;
+		}
+#  endif
+	}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif /* HAVE_PTHREAD */
 
 	result = nutscan_rewind_device(dev_ret);
@@ -1299,7 +1480,23 @@ nutscan_device_t * nutscan_scan_snmp(const char * start_ip, const char * stop_ip
 	NUT_UNUSED_VARIABLE(stop_ip);
 	NUT_UNUSED_VARIABLE(usec_timeout);
 	NUT_UNUSED_VARIABLE(sec);
+
 	return NULL;
 }
 
+/* stub function */
+nutscan_device_t * nutscan_scan_ip_range_snmp(nutscan_ip_range_list_t * irl,
+                                     useconds_t usec_timeout, nutscan_snmp_t * sec)
+{
+	NUT_UNUSED_VARIABLE(irl);
+	NUT_UNUSED_VARIABLE(usec_timeout);
+	NUT_UNUSED_VARIABLE(sec);
+
+	return NULL;
+}
+
+int nutscan_unload_snmp_library(void)
+{
+	return 0;
+}
 #endif /* WITH_SNMP */
diff --git a/tools/nut-scanner/scan_usb.c b/tools/nut-scanner/scan_usb.c
index c24dc09a51..3642602b2c 100644
--- a/tools/nut-scanner/scan_usb.c
+++ b/tools/nut-scanner/scan_usb.c
@@ -1,5 +1,6 @@
 /*
  *  Copyright (C) 2011-2016 - EATON
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -25,7 +26,11 @@
 #include "common.h"
 #include "nut-scan.h"
 
+/* externally visible to nutscan-init */
+int nutscan_unload_usb_library(void);
+
 #ifdef WITH_USB
+
 #include "upsclient.h"
 #include "nutscan-usb.h"
 #include <stdio.h>
@@ -35,17 +40,25 @@
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
+static char *dl_saved_libname = NULL;
+
 static int (*nut_usb_close)(libusb_device_handle *dev);
-static int (*nut_usb_get_string_simple)(libusb_device_handle *dev, int index,
+static int (*nut_usb_control_transfer)(libusb_device_handle *dev,
+		uint8_t request_type, uint8_t bRequest, uint16_t wValue, uint16_t wIndex,
+		unsigned char *data, uint16_t wLength, unsigned int timeout);
+static int (*nut_usb_get_string_with_langid)(libusb_device_handle *dev, int index, int langid,
+		char *buf, size_t buflen);
+/* Fallback implem if the above is not a library symbol */
+static int nut_usb_get_string_with_langid_control_transfer(
+		libusb_device_handle *dev, int index, int langid,
 		char *buf, size_t buflen);
-
 
 /* Compatibility layer between libusb 0.1 and 1.0 */
 #if WITH_LIBUSB_1_0
- #define USB_INIT_SYMBOL "libusb_init"
- #define USB_OPEN_SYMBOL "libusb_open"
- #define USB_CLOSE_SYMBOL "libusb_close"
- #define USB_STRERROR_SYMBOL "libusb_strerror"
+# define USB_INIT_SYMBOL "libusb_init"
+# define USB_OPEN_SYMBOL "libusb_open"
+# define USB_CLOSE_SYMBOL "libusb_close"
+# define USB_STRERROR_SYMBOL "libusb_strerror"
  static int (*nut_usb_open)(libusb_device *dev, libusb_device_handle **handle);
  static int (*nut_usb_init)(libusb_context **ctx);
  static void (*nut_usb_exit)(libusb_context *ctx);
@@ -57,11 +70,14 @@ static int (*nut_usb_get_string_simple)(libusb_device_handle *dev, int index,
  static uint8_t (*nut_usb_get_port_number)(libusb_device *dev);
  static int (*nut_usb_get_device_descriptor)(libusb_device *dev,
 	struct libusb_device_descriptor *desc);
+# define USB_DT_STRING	LIBUSB_DT_STRING
+# define USB_ENDPOINT_IN	LIBUSB_ENDPOINT_IN
+# define USB_REQ_GET_DESCRIPTOR	LIBUSB_REQUEST_GET_DESCRIPTOR
 #else /* => WITH_LIBUSB_0_1 */
- #define USB_INIT_SYMBOL "usb_init"
- #define USB_OPEN_SYMBOL "usb_open"
- #define USB_CLOSE_SYMBOL "usb_close"
- #define USB_STRERROR_SYMBOL "usb_strerror"
+# define USB_INIT_SYMBOL "usb_init"
+# define USB_OPEN_SYMBOL "usb_open"
+# define USB_CLOSE_SYMBOL "usb_close"
+# define USB_STRERROR_SYMBOL "usb_strerror"
  static libusb_device_handle * (*nut_usb_open)(struct usb_device *dev);
  static void (*nut_usb_init)(void);
  static int (*nut_usb_find_busses)(void);
@@ -74,7 +90,16 @@ static int (*nut_usb_get_string_simple)(libusb_device_handle *dev, int index,
  static char * (*nut_usb_strerror)(void);
 #endif /* WITH_LIBUSB_1_0 */
 
-/* return 0 on error; visible externally */
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_usb_library(void)
+{
+	return nutscan_unload_library(&nutscan_avail_usb, &dl_handle, &dl_saved_libname);
+}
+
+/* Return 0 on error; visible externally */
 int nutscan_load_usb_library(const char *libname_path);
 int nutscan_load_usb_library(const char *libname_path)
 {
@@ -88,12 +113,12 @@ int nutscan_load_usb_library(const char *libname_path)
 	}
 
 	if (libname_path == NULL) {
-		fprintf(stderr, "USB library not found. USB search disabled.\n");
+		upsdebugx(0, "USB library not found. USB search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-		fprintf(stderr, "Error initializing lt_init\n");
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
 		return 0;
 	}
 
@@ -102,7 +127,9 @@ int nutscan_load_usb_library(const char *libname_path)
 			dl_error = lt_dlerror();
 			goto err;
 	}
-	lt_dlerror();      /* Clear any existing error */
+
+	/* Clear any existing error */
+	lt_dlerror();
 
 	*(void **) (&nut_usb_init) = lt_dlsym(dl_handle, USB_INIT_SYMBOL);
 	if ((dl_error = lt_dlerror()) != NULL) {
@@ -165,10 +192,10 @@ int nutscan_load_usb_library(const char *libname_path)
 	*(void **) (&nut_usb_get_port_number) = lt_dlsym(dl_handle,
 					"libusb_get_port_number");
 	if ((dl_error = lt_dlerror()) != NULL) {
-			fprintf(stderr,
+			upsdebugx(0, "WARNING: %s: "
 				"While loading USB library (%s), failed to find libusb_get_port_number() : %s. "
-				"The \"busport\" USB matching option will be disabled.\n",
-				libname_path, dl_error);
+				"The \"busport\" USB matching option will be disabled.",
+				__func__, libname_path, dl_error);
 			nut_usb_get_port_number = NULL;
 	}
 
@@ -178,11 +205,20 @@ int nutscan_load_usb_library(const char *libname_path)
 			goto err;
 	}
 
-	*(void **) (&nut_usb_get_string_simple) = lt_dlsym(dl_handle,
-					"libusb_get_string_descriptor_ascii");
+	*(void **) (&nut_usb_control_transfer) = lt_dlsym(dl_handle,
+					"libusb_control_transfer");
 	if ((dl_error = lt_dlerror()) != NULL) {
 			goto err;
 	}
+
+	*(void **) (&nut_usb_get_string_with_langid) = lt_dlsym(dl_handle,
+					"libusb_get_string_descriptor");
+	if ((dl_error = lt_dlerror()) != NULL) {
+			/* This one may be only defined in a header as an inline method;
+			 * then we are adapting it via nut_usb_control_transfer().
+			 */
+			nut_usb_get_string_with_langid = NULL;
+	}
 #else /* for libusb 0.1 */
 	*(void **) (&nut_usb_find_busses) = lt_dlsym(dl_handle,
 					"usb_find_busses");
@@ -210,21 +246,40 @@ int nutscan_load_usb_library(const char *libname_path)
 			goto err;
 	}
 
-	*(void **) (&nut_usb_get_string_simple) = lt_dlsym(dl_handle,
-					"usb_get_string_simple");
+	*(void **) (&nut_usb_control_transfer) = lt_dlsym(dl_handle,
+					"usb_control_msg");
 	if ((dl_error = lt_dlerror()) != NULL) {
 			goto err;
 	}
-#endif /* WITH_LIBUSB_1_0 */
+
+	*(void **) (&nut_usb_get_string_with_langid) = lt_dlsym(dl_handle,
+					"usb_get_string");
+	if ((dl_error = lt_dlerror()) != NULL) {
+			/* See comment above */
+			nut_usb_get_string_with_langid = NULL;
+	}
+#endif /* not WITH_LIBUSB_1_0 => for libusb 0.1 */
+
+	if (nut_usb_get_string_with_langid == NULL) {
+			nut_usb_get_string_with_langid = nut_usb_get_string_with_langid_control_transfer;
+	}
+
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
 
 	return 1;
 
 err:
-	fprintf(stderr,
-		"Cannot load USB library (%s) : %s. USB search disabled.\n",
+	upsdebugx(0,
+		"Cannot load USB library (%s) : %s. USB search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 }
 /* end of dynamic link library stuff */
@@ -247,6 +302,107 @@ static char* is_usb_device_supported(usb_device_id_t *usb_device_id_list,
 	return NULL;
 }
 
+/* This one may be only defined in a header as an inline method;
+ * then we are adapting it via nut_usb_control_transfer() per
+ * https://github.com/libusb/libusb-compat-0.1/blob/eaed7b8f11badaf07a91e07538f6e8842f59eaab/libusb/libusb-dload.h#L165-L171
+ */
+static int nut_usb_get_string_with_langid_control_transfer(
+		libusb_device_handle *dev, int index, int langid,
+		char *buf, size_t buflen)
+{
+	return (*nut_usb_control_transfer)(
+		dev, USB_ENDPOINT_IN, USB_REQ_GET_DESCRIPTOR,
+		(USB_DT_STRING << 8) + index, langid,
+		(unsigned char *)buf, buflen, 1000);
+}
+
+/* Replicated from usb-common.c with consideration for nut-scanner's
+ * use of method pointers instead of direct linking. API neutral,
+ * handles retries. Retries were originally introduced for "Tripp Lite"
+ * devices, see https://github.com/networkupstools/nut/issues/414
+ */
+#define MAX_STRING_DESC_TRIES 3
+
+static int nut_usb_get_string_descriptor(
+	libusb_device_handle *udev,
+	int StringIdx,
+	int langid,
+	char *buf,
+	size_t buflen)
+{
+	int ret = -1;
+	int tries = MAX_STRING_DESC_TRIES;
+
+	while (tries--) {
+		ret = (*nut_usb_get_string_with_langid)(
+			udev, StringIdx,
+			langid, buf, buflen);
+		if (ret >= 0) {
+			break;
+		} else if (tries) {
+			upsdebugx(1, "%s: string descriptor %d request failed, retrying...", __func__, StringIdx);
+			usleep(50000);	/* 50 ms, might help in some cases */
+		}
+	}
+	return ret;
+}
+
+/* Replicated from usb-common.c with consideration for nut-scanner's
+ * use of method pointers instead of direct linking. API neutral,
+ * assumes en_US if langid descriptor is broken */
+static int nut_usb_get_string(
+	libusb_device_handle *udev,
+	int StringIdx,
+	char *buf,
+	size_t buflen)
+{
+	int ret;
+	char buffer[255];
+	int langid;
+	int len;
+	int i;
+
+	if (!udev || StringIdx < 1 || StringIdx > 255) {
+		return -1;
+	}
+
+	/* request langid descriptor */
+	ret = nut_usb_get_string_descriptor(udev, 0, 0, buffer, 4);
+	if (ret < 0)
+		return ret;
+
+	if (ret == 4 && buffer[0] >= 4 && buffer[1] == USB_DT_STRING) {
+		langid = buffer[2] | (buffer[3] << 8);
+	} else {
+		upsdebugx(1, "%s: Broken language identifier, assuming en_US", __func__);
+		langid = 0x0409;
+	}
+
+	/* retrieve string in preferred language */
+	ret = nut_usb_get_string_descriptor(udev, StringIdx, langid, buffer, sizeof(buffer));
+	if (ret < 0) {
+#ifdef WIN32
+		/* only for libusb0 ? */
+		errno = -ret;
+#endif
+		return ret;
+	}
+
+	/* translate simple UTF-16LE to 8-bit */
+	len = ret < (int)buflen ? ret : (int)buflen;
+	len = len / 2 - 1;	/* 16-bit characters, without header */
+	len = len < (int)buflen - 1 ? len : (int)buflen - 1;	/* reserve for null terminator */
+	for (i = 0; i < len; i++) {
+		if (buffer[2 + i * 2 + 1] == 0)
+			buf[i] = buffer[2 + i * 2];
+		else
+			buf[i] = '?';	/* not decoded */
+	}
+	buf[i] = '\0';
+
+	return len;
+}
+
 /* return NULL if error */
 nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 {
@@ -329,7 +485,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 #if WITH_LIBUSB_1_0
 	if ((*nut_usb_init)(NULL) < 0) {
 		(*nut_usb_exit)(NULL);
-		fatal_with_errno(EXIT_FAILURE, "Failed to init libusb 1.0");
+		upsdebug_with_errno(0, "Failed to init libusb 1.0");
+		/* nutscan_avail_usb = 0; */
+		return NULL;
 	}
 #else  /* => WITH_LIBUSB_0_1 */
 	(*nut_usb_init)();
@@ -341,7 +499,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 	devcount = (*nut_usb_get_device_list)(NULL, &devlist);
 	if (devcount <= 0) {
 		(*nut_usb_exit)(NULL);
-		fatal_with_errno(EXIT_FAILURE, "No USB device found");
+		upsdebug_with_errno(0, "No USB device found");
+		/* nutscan_avail_usb = 0; */
+		return NULL;
 	}
 
 	for (i = 0; i < devcount; i++) {
@@ -361,7 +521,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 		if (busname == NULL) {
 			(*nut_usb_free_device_list)(devlist, 1);
 			(*nut_usb_exit)(NULL);
-			fatal_with_errno(EXIT_FAILURE, "Out of memory");
+			upsdebug_with_errno(0, "%s: Out of memory", __func__);
+			/* nutscan_avail_usb = 0; */
+			return NULL;
 		}
 		snprintf(busname, 4, "%03d", bus_num);
 
@@ -369,7 +531,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 		if (device_port == NULL) {
 			(*nut_usb_free_device_list)(devlist, 1);
 			(*nut_usb_exit)(NULL);
-			fatal_with_errno(EXIT_FAILURE, "Out of memory");
+			upsdebug_with_errno(0, "%s: Out of memory", __func__);
+			/* nutscan_avail_usb = 0; */
+			return NULL;
 		} else {
 			uint8_t device_addr = (*nut_usb_get_device_address)(dev);
 			if (device_addr > 0) {
@@ -384,7 +548,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 			if (bus_port == NULL) {
 				(*nut_usb_free_device_list)(devlist, 1);
 				(*nut_usb_exit)(NULL);
-				fatal_with_errno(EXIT_FAILURE, "Out of memory");
+				upsdebug_with_errno(0, "%s: Out of memory", __func__);
+				/* nutscan_avail_usb = 0; */
+				return NULL;
 			} else {
 				uint8_t port_num = (*nut_usb_get_port_number)(dev);
 				if (port_num > 0) {
@@ -422,9 +588,12 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 #if WITH_LIBUSB_1_0
 				ret = (*nut_usb_open)(dev, &udev);
 				if (!udev || ret != LIBUSB_SUCCESS) {
-					fprintf(stderr, "Failed to open device "
-						"bus '%s' device/port '%s' bus/port '%s', skipping: %s\n",
-						busname, device_port, bus_port,
+					upsdebugx(0, "WARNING: %s: "
+						"Failed to open device "
+						"bus '%s' device/port '%s' "
+						"bus/port '%s', skipping: %s",
+						__func__, busname,
+						device_port, bus_port,
 						(*nut_usb_strerror)(ret));
 
 					/* Note: closing is not applicable
@@ -446,9 +615,10 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 				udev = (*nut_usb_open)(dev);
 				if (!udev) {
 					/* TOTHINK: any errno or similar to test? */
-					fprintf(stderr, "Failed to open device "
-						"bus '%s' device/port '%s', skipping: %s\n",
-						busname, device_port,
+					upsdebugx(0, "WARNING: %s: "
+						"Failed to open device "
+						"bus '%s' device/port '%s', skipping: %s",
+						__func__, busname, device_port,
 						(*nut_usb_strerror)());
 					continue;
 				}
@@ -456,7 +626,7 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 
 				/* get serial number */
 				if (iSerialNumber) {
-					ret = (*nut_usb_get_string_simple)(udev,
+					ret = nut_usb_get_string(udev,
 						iSerialNumber, string, sizeof(string));
 					if (ret > 0) {
 						serialnumber = strdup(str_rtrim(string, ' '));
@@ -472,14 +642,16 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 							(*nut_usb_free_device_list)(devlist, 1);
 							(*nut_usb_exit)(NULL);
 #endif	/* WITH_LIBUSB_1_0 */
-							fatal_with_errno(EXIT_FAILURE, "Out of memory");
+							upsdebug_with_errno(0, "%s: Out of memory", __func__);
+							/* nutscan_avail_usb = 0; */
+							return NULL;
 						}
 					}
 				}
 
 				/* get product name */
 				if (iProduct) {
-					ret = (*nut_usb_get_string_simple)(udev,
+					ret = nut_usb_get_string(udev,
 						iProduct, string, sizeof(string));
 					if (ret > 0) {
 						device_name = strdup(str_rtrim(string, ' '));
@@ -496,14 +668,16 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 							(*nut_usb_free_device_list)(devlist, 1);
 							(*nut_usb_exit)(NULL);
 #endif	/* WITH_LIBUSB_1_0 */
-							fatal_with_errno(EXIT_FAILURE, "Out of memory");
+							upsdebug_with_errno(0, "%s: Out of memory", __func__);
+							/* nutscan_avail_usb = 0; */
+							return NULL;
 						}
 					}
 				}
 
 				/* get vendor name */
 				if (iManufacturer) {
-					ret = (*nut_usb_get_string_simple)(udev,
+					ret = nut_usb_get_string(udev,
 						iManufacturer, string, sizeof(string));
 					if (ret > 0) {
 						vendor_name = strdup(str_rtrim(string, ' '));
@@ -521,15 +695,16 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 							(*nut_usb_free_device_list)(devlist, 1);
 							(*nut_usb_exit)(NULL);
 #endif	/* WITH_LIBUSB_1_0 */
-							fatal_with_errno(EXIT_FAILURE, "Out of memory");
+							upsdebug_with_errno(0, "%s: Out of memory", __func__);
+							/* nutscan_avail_usb = 0; */
+							return NULL;
 						}
 					}
 				}
 
 				nut_dev = nutscan_new_device();
 				if (nut_dev == NULL) {
-					fprintf(stderr,
-						"Memory allocation error\n");
+					upsdebugx(0, "%s: Memory allocation error", __func__);
 					nutscan_free_device(current_nut_dev);
 					free(serialnumber);
 					free(device_name);
@@ -557,36 +732,87 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 				}
 				nut_dev->port = strdup("auto");
 
-				sprintf(string, "%04X", VendorID);
-				nutscan_add_option_to_device(nut_dev,
-					"vendorid",
-					string);
-
-				sprintf(string, "%04X", ProductID);
-				nutscan_add_option_to_device(nut_dev,
-					"productid",
-					string);
-
-				if (device_name) {
+				/* FIXME: https://github.com/networkupstools/nut/pull/1763
+				 * and linked issues: some drivers do not use
+				 * the common nut_usb_addvars() method, and
+				 * do not otherwise support these options:
+				 */
+				if (strncmp(driver_name, "bcmxcp_usb", 10)
+				 && strncmp(driver_name, "richcomm_usb", 12)
+				 && strncmp(driver_name, "nutdrv_atcl_usb", 15)
+				) {
+					sprintf(string, "%04X", VendorID);
 					nutscan_add_option_to_device(nut_dev,
-						"product",
-						device_name);
-					free(device_name);
-					device_name = NULL;
-				}
+						"vendorid",
+						string);
 
-				if (serialnumber) {
+					sprintf(string, "%04X", ProductID);
 					nutscan_add_option_to_device(nut_dev,
-						"serial",
-						serialnumber);
-					free(serialnumber);
-					serialnumber = NULL;
+						"productid",
+						string);
+
+					if (device_name) {
+						nutscan_add_option_to_device(nut_dev,
+							"product",
+							device_name);
+						free(device_name);
+						device_name = NULL;
+					}
+
+					if (serialnumber) {
+						nutscan_add_option_to_device(nut_dev,
+							"serial",
+							serialnumber);
+						free(serialnumber);
+						serialnumber = NULL;
+					}
+				} else {
+					sprintf(string, "%04X", VendorID);
+					nutscan_add_commented_option_to_device(nut_dev,
+						"vendorid",
+						string,
+						"");
+
+					sprintf(string, "%04X", ProductID);
+					nutscan_add_commented_option_to_device(nut_dev,
+						"productid",
+						string,
+						"");
+
+					if (device_name) {
+						nutscan_add_commented_option_to_device(nut_dev,
+							"product",
+							device_name,
+							"");
+						free(device_name);
+						device_name = NULL;
+					}
+
+					if (serialnumber) {
+						nutscan_add_commented_option_to_device(nut_dev,
+							"serial",
+							serialnumber,
+							"");
+						free(serialnumber);
+						serialnumber = NULL;
+					}
 				}
 
 				if (vendor_name) {
-					nutscan_add_option_to_device(nut_dev,
-						"vendor",
-						vendor_name);
+					/* NOTE: nutdrv_atcl_usb recognizes
+					 * "vendor" but not other opts */
+					if (strncmp(driver_name, "bcmxcp_usb", 10)
+					 && strncmp(driver_name, "richcomm_usb", 12)
+					) {
+						nutscan_add_option_to_device(nut_dev,
+							"vendor",
+							vendor_name);
+					} else {
+						nutscan_add_commented_option_to_device(nut_dev,
+							"vendor",
+							vendor_name,
+							"");
+					}
 					free(vendor_name);
 					vendor_name = NULL;
 				}
@@ -612,6 +838,8 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 				}
 #endif	/* WITH_LIBUSB_1_0 */
 
+				/* FIXME: Detect and suggest HID index, interface number, etc. */
+
 				if (scanopts->report_bcdDevice) {
 					/* Not currently matched by drivers, hence commented
 					 * for now even if requested via scanopts */
@@ -659,4 +887,9 @@ nutscan_device_t * nutscan_scan_usb(nutscan_usb_t * scanopts)
 	return NULL;
 }
 
+
+int nutscan_unload_usb_library(void)
+{
+	return 0;
+}
 #endif /* WITH_USB */
diff --git a/tools/nut-scanner/scan_xml_http.c b/tools/nut-scanner/scan_xml_http.c
index 490d2b9b21..f8729b499e 100644
--- a/tools/nut-scanner/scan_xml_http.c
+++ b/tools/nut-scanner/scan_xml_http.c
@@ -2,6 +2,7 @@
  *  Copyright (C) 2011 - EATON
  *  Copyright (C) 2016 - EATON - IP addressed XML scan
  *  Copyright (C) 2016-2021 - EATON - Various threads-related improvements
+ *  Copyright (C) 2020-2024 - Jim Klimov <jimklimov+nut@gmail.com> - support and modernization of codebase
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -29,35 +30,39 @@
 #include "nut-scan.h"
 #include "nut_stdint.h"
 
+/* externally visible to nutscan-init */
+int nutscan_unload_neon_library(void);
+
 #ifdef WITH_NEON
+
 #ifndef WIN32
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netdb.h>
-#include <arpa/inet.h>
-#include <netinet/in.h>
-#include <sys/select.h>
-#define SOCK_OPT_CAST
+# include <sys/types.h>
+# include <sys/socket.h>
+# include <netdb.h>
+# include <arpa/inet.h>
+# include <netinet/in.h>
+# include <sys/select.h>
+# define SOCK_OPT_CAST
 #else
-#define SOCK_OPT_CAST (char*)
+# define SOCK_OPT_CAST (char*)
 /* Those 2 files for support of getaddrinfo, getnameinfo and freeaddrinfo
    on Windows 2000 and older versions */
-#include <ws2tcpip.h>
-#include <wspiapi.h>
+# include <ws2tcpip.h>
+# include <wspiapi.h>
 # if ! HAVE_INET_PTON
 #  include "wincompat.h"	/* fallback inet_ntop where needed */
 # endif
-#endif
+#endif	/* WIN32 */
 
 #include <string.h>
 #include <stdio.h>
-#include <errno.h>
 #include <ne_xml.h>
 #include <ltdl.h>
 
 /* dynamic link library stuff */
 static lt_dlhandle dl_handle = NULL;
 static const char *dl_error = NULL;
+static char *dl_saved_libname = NULL;
 
 static void (*nut_ne_xml_push_handler)(ne_xml_parser *p,
                             ne_xml_startelm_cb *startelm,
@@ -69,6 +74,8 @@ static int (*nut_ne_xml_failed)(ne_xml_parser *p);
 static ne_xml_parser * (*nut_ne_xml_create)(void);
 static int (*nut_ne_xml_parse)(ne_xml_parser *p, const char *block, size_t len);
 
+/* This variable collects device(s) from a sequential or parallel scan,
+ * is returned to caller, and cleared to allow subsequent independent scans */
 static nutscan_device_t * dev_ret = NULL;
 #ifdef HAVE_PTHREAD
 static pthread_mutex_t dev_mutex;
@@ -81,7 +88,16 @@ typedef enum ebool { FALSE = 0, TRUE } bool_t;
 typedef int bool_t;
 #endif
 
-/* return 0 on error; visible externally */
+/* Return 0 on success, -1 on error e.g. "was not loaded";
+ * other values may be possible if lt_dlclose() errors set them;
+ * visible externally */
+int nutscan_unload_library(int *avail, lt_dlhandle *pdl_handle, char **libpath);
+int nutscan_unload_neon_library(void)
+{
+	return nutscan_unload_library(&nutscan_avail_xml_http, &dl_handle, &dl_saved_libname);
+}
+
+/* Return 0 on error; visible externally */
 int nutscan_load_neon_library(const char *libname_path);
 int nutscan_load_neon_library(const char *libname_path)
 {
@@ -95,12 +111,12 @@ int nutscan_load_neon_library(const char *libname_path)
 	}
 
 	if (libname_path == NULL) {
-		fprintf(stderr, "Neon library not found. XML search disabled.\n");
+		upsdebugx(0, "Neon library not found. XML search disabled.");
 		return 0;
 	}
 
 	if (lt_dlinit() != 0) {
-		fprintf(stderr, "Error initializing lt_init\n");
+		upsdebugx(0, "%s: Error initializing lt_dlinit", __func__);
 		return 0;
 	}
 
@@ -110,7 +126,9 @@ int nutscan_load_neon_library(const char *libname_path)
 		goto err;
 	}
 
-	lt_dlerror();      /* Clear any existing error */
+	/* Clear any existing error */
+	lt_dlerror();
+
 	*(void **) (&nut_ne_xml_push_handler) = lt_dlsym(dl_handle,
 						"ne_xml_push_handler");
 	if ((dl_error = lt_dlerror()) != NULL) {
@@ -137,15 +155,25 @@ int nutscan_load_neon_library(const char *libname_path)
 		goto err;
 	}
 
+	if (dl_saved_libname)
+		free(dl_saved_libname);
+	dl_saved_libname = xstrdup(libname_path);
+
 	return 1;
+
 err:
-	fprintf(stderr,
-		"Cannot load XML library (%s) : %s. XML search disabled.\n",
+	upsdebugx(0,
+		"Cannot load XML library (%s) : %s. XML search disabled.",
 		libname_path, dl_error);
 	dl_handle = (void *)1;
 	lt_dlexit();
+	if (dl_saved_libname) {
+		free(dl_saved_libname);
+		dl_saved_libname = NULL;
+	}
 	return 0;
 }
+/* end of dynamic link library stuff */
 
 /* A start-element callback for element with given namespace/name. */
 static int startelm_cb(void *userdata, int parent, const char *nspace, const char *name, const char **atts) {
@@ -178,17 +206,23 @@ static int startelm_cb(void *userdata, int parent, const char *nspace, const cha
 	return result;
 }
 
-static void * nutscan_scan_xml_http_generic(void * arg)
+/* Performs a (parallel-able) NetXML protocol scan of one remote host:port.
+ * Returns NULL, updates global dev_ret when a scan is successful.
+ * FREES the caller's copy of "arg" and "hostname" in it, if applicable.
+ */
+static void * nutscan_scan_xml_http_thready(void * arg)
 {
 	nutscan_xml_t * sec = (nutscan_xml_t *)arg;
 	char *scanMsg = "<SCAN_REQUEST/>";
-/* Note: at this time the HTTP/XML scan is in fact not implemented - just the UDP part */
+	/* Note: at this time the HTTP/XML scan is
+	 * in fact not implemented - just the UDP part */
 /*	uint16_t port_http = 80; */
 	uint16_t port_udp = 4679;
-/* A NULL "ip" causes a broadcast scan; otherwise the single ip address is queried directly */
+	/* A NULL "ip" causes a broadcast scan; otherwise
+	 * the single ip address is queried directly */
 	char *ip = NULL;
 	useconds_t usec_timeout = 0;
-	int peerSocket;
+	int peerSocket = -1;
 	int sockopt_on = 1;
 	struct sockaddr_in sockAddress_udp;
 	socklen_t sockAddressLength = sizeof(sockAddress_udp);
@@ -200,17 +234,9 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 	ssize_t recv_size;
 	int i;
 	nutscan_device_t * nut_dev = NULL;
-#ifdef WIN32
-	WSADATA WSAdata;
-#endif
 
 	memset(&sockAddress_udp, 0, sizeof(sockAddress_udp));
 
-#ifdef WIN32
-	WSAStartup(2,&WSAdata);
-	atexit((void(*)(void))WSACleanup);
-#endif
-
 	if (sec != NULL) {
 /*		if (sec->port_http > 0 && sec->port_http <= 65534)
  *			port_http = sec->port_http; */
@@ -225,34 +251,36 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 		usec_timeout = 5000000; /* Driver default : 5sec */
 
 	if (!nutscan_avail_xml_http) {
-		return NULL;
+		goto end_free;
 	}
 
 	if ((peerSocket = socket(AF_INET, SOCK_DGRAM, 0)) == -1) {
-		fprintf(stderr, "Error creating socket\n");
-		return NULL;
+		upsdebugx(0, "%s: Error creating socket for %s",
+			__func__, ip ? ip : "broadcast");
+		goto end_free;
 	}
 
-/* FIXME : Per http://stackoverflow.com/questions/683624/udp-broadcast-on-all-interfaces
- * A single sendto() generates a single packet, so one must iterate all known interfaces... */
+	/* FIXME : Per http://stackoverflow.com/questions/683624/udp-broadcast-on-all-interfaces
+	 * A single sendto() generates a single packet,
+	 * so one must iterate all known interfaces... */
 #define MAX_RETRIES 3
 	for (i = 0; i != MAX_RETRIES ; i++) {
 		/* Initialize socket */
 		sockAddress_udp.sin_family = AF_INET;
 		if (ip == NULL) {
 			upsdebugx(2,
-				"nutscan_scan_xml_http_generic() : scanning connected network segment(s) "
+				"%s: scanning connected network segment(s) "
 				"with a broadcast, attempt %d of %d with a timeout of %" PRIdMAX " usec",
-				(i + 1), MAX_RETRIES, (uintmax_t)usec_timeout);
+				__func__, (i + 1), MAX_RETRIES, (uintmax_t)usec_timeout);
 			sockAddress_udp.sin_addr.s_addr = INADDR_BROADCAST;
 			setsockopt(peerSocket, SOL_SOCKET, SO_BROADCAST,
 				SOCK_OPT_CAST &sockopt_on,
 				sizeof(sockopt_on));
 		} else {
 			upsdebugx(2,
-				"nutscan_scan_xml_http_generic() : scanning IP '%s' with a unicast, "
+				"%s: scanning IP '%s' with a unicast, "
 				"attempt %d of %d with a timeout of %" PRIdMAX " usec",
-				ip, (i + 1), MAX_RETRIES, (uintmax_t)usec_timeout);
+				__func__, ip, (i + 1), MAX_RETRIES, (uintmax_t)usec_timeout);
 			inet_pton(AF_INET, ip, &(sockAddress_udp.sin_addr));
 		}
 		sockAddress_udp.sin_port = htons(port_udp);
@@ -262,8 +290,9 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 			(struct sockaddr *)&sockAddress_udp,
 			sockAddressLength) <= 0
 		) {
-			fprintf(stderr,
-				"Error sending Eaton <SCAN_REQUEST/> to %s, #%d/%d\n",
+			upsdebugx(0, "%s: "
+				"Error sending Eaton <SCAN_REQUEST/> to %s, #%d/%d",
+				__func__,
 				(ip ? ip : "<broadcast>"), (i + 1), MAX_RETRIES);
 			usleep(usec_timeout);
 			continue;
@@ -277,9 +306,9 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 			timeout.tv_sec = usec_timeout / 1000000;
 			timeout.tv_usec = usec_timeout % 1000000;
 
-			upsdebugx(5, "nutscan_scan_xml_http_generic() : sent request to %s, "
+			upsdebugx(5, "%s: sent request to %s, "
 				"loop #%d/%d, waiting for responses",
-				(ip ? ip : "<broadcast>"), (i + 1), MAX_RETRIES);
+				__func__, (ip ? ip : "<broadcast>"), (i + 1), MAX_RETRIES);
 			while ((ret = select(peerSocket + 1, &fds, NULL, NULL,
 						&timeout))
 			) {
@@ -287,17 +316,17 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 				int	parserFailed;
 
 				retNum ++;
-				upsdebugx(5, "nutscan_scan_xml_http_generic() : request to %s, "
+				upsdebugx(5, "%s: request to %s, "
 					"loop #%d/%d, response #%d",
-					(ip ? ip : "<broadcast>"), (i + 1), MAX_RETRIES, retNum);
+					__func__, (ip ? ip : "<broadcast>"), (i + 1), MAX_RETRIES, retNum);
 
 				timeout.tv_sec = usec_timeout / 1000000;
 				timeout.tv_usec = usec_timeout % 1000000;
 
 				if (ret == -1) {
-					fprintf(stderr,
-						"Error waiting on \
-						socket: %d\n", errno);
+					upsdebug_with_errno(0,
+						"%s: Error waiting on socket",
+						__func__);
 					break;
 				}
 
@@ -308,9 +337,9 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 					&sockAddressLength);
 
 				if (recv_size < 0) {
-					fprintf(stderr,
-						"Error reading \
-						socket: %d, #%d/%d\n", errno, (i + 1), MAX_RETRIES);
+					upsdebug_with_errno(0, "%s: "
+						"Error reading socket: #%d/%d",
+						__func__, (i + 1), MAX_RETRIES);
 					usleep(usec_timeout);
 					continue;
 				}
@@ -321,15 +350,15 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 					sizeof(string), NULL, 0,
 					NI_NUMERICHOST) != 0
 				) {
-					fprintf(stderr,
-						"Error converting IP address: %d\n", errno);
+					upsdebug_with_errno(0, "%s: "
+						"Error converting IP address", __func__);
 					usleep(usec_timeout);
 					continue;
 				}
 
 				nut_dev = nutscan_new_device();
 				if (nut_dev == NULL) {
-					fprintf(stderr, "Memory allocation error\n");
+					upsdebugx(0, "%s: Memory allocation error", __func__);
 					goto end_abort;
 				}
 
@@ -337,9 +366,9 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 				pthread_mutex_lock(&dev_mutex);
 #endif
 				upsdebugx(5,
-					"Some host at IP %s replied to NetXML UDP request on port %d, "
+					"%s: Some host at IP %s replied to NetXML UDP request on port %d, "
 					"inspecting the response...",
-					string, port_udp);
+					__func__, string, port_udp);
 				nut_dev->type = TYPE_XML;
 				/* Try to read device type */
 				parser = (*nut_ne_xml_create)();
@@ -353,11 +382,12 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 				if (parserFailed == 0) {
 					nut_dev->driver = strdup("netxml-ups");
 					sprintf(buf, "http://%s", string);
+					/* FIXME: Should the IPv6 address here be bracketed?
+					 *  Does our driver support the notation? */
 					nut_dev->port = strdup(buf);
 					upsdebugx(3,
-						"nutscan_scan_xml_http_generic(): "
-						"Adding configuration for driver='%s' port='%s'",
-						nut_dev->driver, nut_dev->port);
+						"%s: Adding configuration for driver='%s' port='%s'",
+						__func__, nut_dev->driver, nut_dev->port);
 					dev_ret = nutscan_add_device_to_device(
 						dev_ret, nut_dev);
 #ifdef HAVE_PTHREAD
@@ -366,10 +396,10 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 				}
 				else
 				{
-					fprintf(stderr,
+					upsdebugx(0, "WARNING: %s: "
 						"Device at IP %s replied with NetXML but was not deemed compatible "
-						"with 'netxml-ups' driver (unsupported protocol version, etc.)\n",
-						string);
+						"with 'netxml-ups' driver (unsupported protocol version, etc.)",
+						__func__, string);
 					nutscan_free_device(nut_dev);
 					nut_dev = NULL;
 #ifdef HAVE_PTHREAD
@@ -385,348 +415,462 @@ static void * nutscan_scan_xml_http_generic(void * arg)
 
 				if (ip != NULL) {
 					upsdebugx(2,
-						"nutscan_scan_xml_http_generic(): we collected one reply "
+						"%s: we collected one reply "
 						"to unicast for %s (repsponse from %s), done",
-						ip, string);
+						__func__, ip, string);
 					goto end;
 				}
 			} /* while select() responses */
 			if (ip == NULL && dev_ret != NULL) {
 				upsdebugx(2,
-					"nutscan_scan_xml_http_generic(): we collected one round of replies "
-					"to broadcast with no errors, done");
+					"%s: we collected one round of replies "
+					"to broadcast with no errors, done", __func__);
 				goto end;
 			}
 		}
 	}
 	upsdebugx(2,
-		"nutscan_scan_xml_http_generic(): no replies collected for %s, done",
-		(ip ? ip : "<broadcast>"));
+		"%s: no replies collected for %s, done",
+		__func__, (ip ? ip : "<broadcast>"));
 	goto end;
 
 end_abort:
 	upsdebugx(1,
-		"Had to abort nutscan_scan_xml_http_generic() for %s, see fatal details above",
-		(ip ? ip : "<broadcast>"));
+		"%s: Had to abort scan for %s, see fatal details above",
+		__func__, (ip ? ip : "<broadcast>"));
+
 end:
-	if (ip != NULL) /* do not free "ip", it comes from caller */
+	/* Broadcast is also a socket! */
+	if (peerSocket != -1)
 		close(peerSocket);
+
+end_free:
+	/* free resources which come from the caller
+	 * (in parallel runs, nobody else can reap them)
+	 */
+	if (ip != NULL)
+		free(ip);
+	if (sec != NULL)
+		free(sec);
+
 	return NULL;
 }
 
 nutscan_device_t * nutscan_scan_xml_http_range(const char * start_ip, const char * end_ip, useconds_t usec_timeout, nutscan_xml_t * sec)
+{
+	nutscan_device_t	*ndret;
+
+	/* Are we scanning locally, or through the network? */
+	if (start_ip || end_ip) {
+		nutscan_ip_range_list_t irl;
+
+		nutscan_init_ip_ranges(&irl);
+		nutscan_add_ip_range(&irl, (char *)start_ip, (char *)end_ip);
+
+		ndret = nutscan_scan_ip_range_xml_http(&irl, usec_timeout, sec);
+
+		/* Avoid nuking caller's strings here */
+		irl.ip_ranges->start_ip = NULL;
+		irl.ip_ranges->end_ip = NULL;
+		nutscan_free_ip_ranges(&irl);
+	} else {
+		/* Probe local device */
+		ndret = nutscan_scan_ip_range_xml_http(NULL, usec_timeout, sec);
+	}
+
+	return ndret;
+}
+
+nutscan_device_t * nutscan_scan_ip_range_xml_http(nutscan_ip_range_list_t * irl, useconds_t usec_timeout, nutscan_xml_t * sec)
 {
 	bool_t pass = TRUE; /* Track that we may spawn a scanning thread */
-	nutscan_xml_t * tmp_sec = NULL;
 	nutscan_device_t * result = NULL;
+	nutscan_xml_t * tmp_sec = NULL;
 
 	if (!nutscan_avail_xml_http) {
 		return NULL;
 	}
 
-	if (start_ip == NULL && end_ip != NULL) {
-		start_ip = end_ip;
-	}
-
-	if (start_ip == NULL) {
-		upsdebugx(1, "Scanning XML/HTTP bus using broadcast.");
+	/* We assume the list is maintained by our methods, so should not have
+	 * null addresses. But just in case - check for it a little tiny once.
+	 */
+	if (irl == NULL || irl->ip_ranges == NULL
+	 || irl->ip_ranges->start_ip == NULL || irl->ip_ranges->end_ip == NULL
+	) {
+		upsdebugx(1, "%s: Scanning XML/HTTP bus using broadcast.", __func__);
+		/* Fall through to after the if/else clause */
 	} else {
-		if ((start_ip == end_ip) || (end_ip == NULL) || (0 == strncmp(start_ip, end_ip, 128))) {
-			upsdebugx(1, "Scanning XML/HTTP bus for single IP (%s).", start_ip);
-		} else {
-			/* Iterate the range of IPs to scan */
-			nutscan_ip_iter_t ip;
-			char * ip_str = NULL;
+		/* Iterate the one or a range of IPs to scan */
+		nutscan_ip_range_list_iter_t ip;
+		char * ip_str = NULL;
+
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
-			sem_t * semaphore = nutscan_semaphore();
-			sem_t   semaphore_scantype_inst;
-			sem_t * semaphore_scantype = &semaphore_scantype_inst;
-# endif /* HAVE_SEMAPHORE */
-			pthread_t thread;
-			nutscan_thread_t * thread_array = NULL;
-			size_t thread_count = 0, i;
-# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE)
-			size_t  max_threads_scantype = max_threads_netxml;
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		sem_t * semaphore = nutscan_semaphore();
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+		sem_t   semaphore_scantype_inst;
+		sem_t * semaphore_scantype = &semaphore_scantype_inst;
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+		sem_t * semaphore_scantype = NULL;
+#  endif
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
+		pthread_t thread;
+		nutscan_thread_t * thread_array = NULL;
+		size_t thread_count = 0, i;
+# if (defined HAVE_PTHREAD_TRYJOIN) || (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		size_t  max_threads_scantype = max_threads_netxml;
 # endif
+#endif	/* HAVE_PTHREAD */
+
+		if (irl->ip_ranges_count == 1
+		&& (irl->ip_ranges->start_ip == irl->ip_ranges->end_ip
+		    || !strcmp(irl->ip_ranges->start_ip, irl->ip_ranges->end_ip)
+		)) {
+			upsdebugx(1, "%s: Scanning XML/HTTP bus for single IP address: %s",
+				__func__, irl->ip_ranges->start_ip);
+		} else {
+			upsdebugx(1, "%s: Scanning XML/HTTP bus for IP address range(s): %s",
+				__func__, nutscan_stringify_ip_ranges(irl));
+		}
 
-			pthread_mutex_init(&dev_mutex, NULL);
+#ifdef HAVE_PTHREAD
+		pthread_mutex_init(&dev_mutex, NULL);
 
-# ifdef HAVE_SEMAPHORE
-			if (max_threads_scantype > 0) {
-				if (SIZE_MAX > UINT_MAX && max_threads_scantype > UINT_MAX) {
-					upsdebugx(1,
-						"WARNING: %s: Limiting max_threads_scantype to range acceptable for sem_init()",
-						__func__);
-					max_threads_scantype = UINT_MAX - 1;
-				}
-				sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype);
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		if (max_threads_scantype > 0) {
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic push
+#endif
+#ifdef HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic ignored "-Wunreachable-code"
+#endif
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunreachable-code"
+#endif
+			/* Different platforms, different sizes, none fits all... */
+			if (SIZE_MAX > UINT_MAX && max_threads_scantype > UINT_MAX) {
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+#ifdef HAVE_PRAGMAS_FOR_GCC_DIAGNOSTIC_IGNORED_UNREACHABLE_CODE
+#pragma GCC diagnostic pop
+#endif
+				upsdebugx(1,
+					"WARNING: %s: Limiting max_threads_scantype to range acceptable for " REPORT_SEM_INIT_METHOD "()",
+					__func__);
+				max_threads_scantype = UINT_MAX - 1;
 			}
-# endif /* HAVE_SEMAPHORE */
+
+			upsdebugx(4, "%s: " REPORT_SEM_INIT_METHOD "() for %" PRIuSIZE " threads", __func__, max_threads_scantype);
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+			if (sem_init(semaphore_scantype, 0, (unsigned int)max_threads_scantype)) {
+				upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+				max_threads_scantype = 0;
+			}
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+			if (SEM_FAILED == (semaphore_scantype = sem_open(SEMNAME_NETXML, O_CREAT, 0644, (unsigned int)max_threads_scantype))) {
+				upsdebug_with_errno(4, "%s: " REPORT_SEM_INIT_METHOD "() failed", __func__);
+				semaphore_scantype = NULL;
+				max_threads_scantype = 0;
+			}
+#  endif
+		}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 
 #endif /* HAVE_PTHREAD */
 
-			ip_str = nutscan_ip_iter_init(&ip, start_ip, end_ip);
+		ip_str = nutscan_ip_ranges_iter_init(&ip, irl);
 
-			while (ip_str != NULL) {
+		while (ip_str != NULL) {
 #ifdef HAVE_PTHREAD
-				/* NOTE: With many enough targets to scan, this can crash
-				 * by spawning too many children; add a limit and loop to
-				 * "reap" some already done with their work. And probably
-				 * account them in thread_array[] as something to not wait
-				 * for below in pthread_join()...
+			/* NOTE: With many enough targets to scan, this can crash
+			 * by spawning too many children; add a limit and loop to
+			 * "reap" some already done with their work. And probably
+			 * account them in thread_array[] as something to not wait
+			 * for below in pthread_join()...
+			 */
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+			/* Just wait for someone to free a semaphored slot,
+			 * if none are available, and then/otherwise grab one
+			 */
+			if (thread_array == NULL) {
+				/* Starting point, or after a wait to complete
+				 * all earlier runners */
+				if (max_threads_scantype > 0)
+					sem_wait(semaphore_scantype);
+				sem_wait(semaphore);
+				pass = TRUE;
+			} else {
+				/* If successful (the lock was acquired),
+				 * sem_wait() and sem_trywait() will return 0.
+				 * Otherwise, -1 is returned and errno is set,
+				 * and the state of the semaphore is unchanged.
 				 */
-
-# ifdef HAVE_SEMAPHORE
-				/* Just wait for someone to free a semaphored slot,
-				 * if none are available, and then/otherwise grab one
-				 */
-				if (thread_array == NULL) {
-					/* Starting point, or after a wait to complete
-					 * all earlier runners */
-			if (max_threads_scantype > 0)
-				sem_wait(semaphore_scantype);
-					sem_wait(semaphore);
-					pass = TRUE;
-				} else {
-			pass = ((max_threads_scantype == 0 || sem_trywait(semaphore_scantype) == 0) &&
-			        sem_trywait(semaphore) == 0);
-				}
+				int	stwST = sem_trywait(semaphore_scantype);
+				int	stwS  = sem_trywait(semaphore);
+				pass = ((max_threads_scantype == 0 || stwST == 0) && stwS == 0);
+				upsdebugx(4, "%s: max_threads_scantype=%" PRIuSIZE
+					" curr_threads=%" PRIuSIZE
+					" thread_count=%" PRIuSIZE
+					" stwST=%d stwS=%d pass=%d",
+					__func__, max_threads_scantype,
+					curr_threads, thread_count,
+					stwST, stwS, pass
+				);
+			}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
-				/* A somewhat naive and brute-force solution for
-				 * systems without a semaphore.h. This may suffer
-				 * some off-by-one errors, using a few more threads
-				 * than intended (if we race a bit at the wrong time,
-				 * probably up to one per enabled scanner routine).
-				 */
-
-				/* TOTHINK: Should there be a threadcount_mutex when
-				 * we just read the value in if() and while() below?
-				 * At worst we would overflow the limit a bit due to
-				 * other protocol scanners...
-				 */
-		if (curr_threads >= max_threads
-		|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
-		) {
-					upsdebugx(2, "%s: already running %" PRIuSIZE " scanning threads "
-						"(launched overall: %" PRIuSIZE "), "
-						"waiting until some would finish",
-						__func__, curr_threads, thread_count);
-			while (curr_threads >= max_threads
-			   || (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+			/* A somewhat naive and brute-force solution for
+			 * systems without a semaphore.h. This may suffer
+			 * some off-by-one errors, using a few more threads
+			 * than intended (if we race a bit at the wrong time,
+			 * probably up to one per enabled scanner routine).
+			 */
+
+			/* TOTHINK: Should there be a threadcount_mutex when
+			 * we just read the value in if() and while() below?
+			 * At worst we would overflow the limit a bit due to
+			 * other protocol scanners...
+			 */
+			if (curr_threads >= max_threads
+			|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
 			) {
-						for (i = 0; i < thread_count ; i++) {
-							int ret;
-
-							if (!thread_array[i].active) continue;
-
-							pthread_mutex_lock(&threadcount_mutex);
-							upsdebugx(3, "%s: Trying to join thread #%i...", __func__, i);
-							ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
-							switch (ret) {
-								case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
-									upsdebugx(5, "%s: Was thread #%" PRIuSIZE " joined earlier?", __func__, i);
-									break;
-								case 0:         /* thread exited */
-									if (curr_threads > 0) {
-										curr_threads --;
-										upsdebugx(4, "%s: Joined a finished thread #%" PRIuSIZE, __func__, i);
-									} else {
-										/* threadcount_mutex fault? */
-										upsdebugx(0, "WARNING: %s: Accounting of thread count "
-											"says we are already at 0", __func__);
-									}
-									thread_array[i].active = FALSE;
-									break;
-								case EBUSY:     /* actively running */
-									upsdebugx(6, "%s: thread #%" PRIuSIZE " still busy (%i)",
-										__func__, i, ret);
-									break;
-								case EDEADLK:   /* Errors with thread interactions... bail out? */
-								case EINVAL:    /* Errors with thread interactions... bail out? */
-								default:        /* new pthreads abilities? */
-									upsdebugx(5, "%s: thread #%" PRIuSIZE " reported code %i",
-										__func__, i, ret);
-									break;
-							}
-							pthread_mutex_unlock(&threadcount_mutex);
-						}
+				upsdebugx(2, "%s: already running %" PRIuSIZE " scanning threads "
+					"(launched overall: %" PRIuSIZE "), "
+					"waiting until some would finish",
+					__func__, curr_threads, thread_count);
 
-				if (curr_threads >= max_threads
-				|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+				while (curr_threads >= max_threads
+				   || (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
 				) {
-							usleep (10000); /* microSec's, so 0.01s here */
+					for (i = 0; i < thread_count ; i++) {
+						int ret;
+
+						if (!thread_array[i].active) continue;
+
+						pthread_mutex_lock(&threadcount_mutex);
+						upsdebugx(3, "%s: Trying to join thread #%" PRIuSIZE "...", __func__, i);
+						ret = pthread_tryjoin_np(thread_array[i].thread, NULL);
+						switch (ret) {
+							case ESRCH:     /* No thread with the ID thread could be found - already "joined"? */
+								upsdebugx(5, "%s: Was thread #%" PRIuSIZE " joined earlier?", __func__, i);
+								break;
+							case 0:         /* thread exited */
+								if (curr_threads > 0) {
+									curr_threads --;
+									upsdebugx(4, "%s: Joined a finished thread #%" PRIuSIZE, __func__, i);
+								} else {
+									/* threadcount_mutex fault? */
+									upsdebugx(0, "WARNING: %s: Accounting of thread count "
+										"says we are already at 0", __func__);
+								}
+								thread_array[i].active = FALSE;
+								break;
+							case EBUSY:     /* actively running */
+								upsdebugx(6, "%s: thread #%" PRIuSIZE " still busy (%i)",
+									__func__, i, ret);
+								break;
+							case EDEADLK:   /* Errors with thread interactions... bail out? */
+							case EINVAL:    /* Errors with thread interactions... bail out? */
+							default:        /* new pthreads abilities? */
+								upsdebugx(5, "%s: thread #%" PRIuSIZE " reported code %i",
+									__func__, i, ret);
+								break;
 						}
+						pthread_mutex_unlock(&threadcount_mutex);
+					}
+
+					if (curr_threads >= max_threads
+					|| (curr_threads >= max_threads_scantype && max_threads_scantype > 0)
+					) {
+							usleep (10000); /* microSec's, so 0.01s here */
 					}
-					upsdebugx(2, "%s: proceeding with scan", __func__);
 				}
-				/* NOTE: No change to default "pass" in this ifdef:
-				 * if we got to this line, we have a slot to use */
+				upsdebugx(2, "%s: proceeding with scan", __func__);
+			}
+
+			/* NOTE: No change to default "pass" in this ifdef:
+			 * if we got to this line, we have a slot to use */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
 
-				if (pass) {
-					tmp_sec = malloc(sizeof(nutscan_xml_t));
-					if (tmp_sec == NULL) {
-						fprintf(stderr,
-							"Memory allocation error\n");
-						return NULL;
-					}
-					memcpy(tmp_sec, sec, sizeof(nutscan_xml_t));
-					tmp_sec->peername = ip_str;
-					if (tmp_sec->usec_timeout <= 0) {
-						tmp_sec->usec_timeout = usec_timeout;
-					}
+			if (pass) {
+				tmp_sec = malloc(sizeof(nutscan_xml_t));
+				if (tmp_sec == NULL) {
+					upsdebugx(0, "%s: Memory allocation error", __func__);
+					break;
+				}
+
+				memcpy(tmp_sec, sec, sizeof(nutscan_xml_t));
+				tmp_sec->peername = ip_str;
+				if (tmp_sec->usec_timeout <= 0) {
+					tmp_sec->usec_timeout = usec_timeout;
+				}
 
 #ifdef HAVE_PTHREAD
-					if (pthread_create(&thread, NULL, nutscan_scan_xml_http_generic, (void *)tmp_sec) == 0) {
-						nutscan_thread_t	*new_thread_array;
+				if (pthread_create(&thread, NULL, nutscan_scan_xml_http_thready, (void*)tmp_sec) == 0) {
+					nutscan_thread_t	*new_thread_array;
 # ifdef HAVE_PTHREAD_TRYJOIN
-						pthread_mutex_lock(&threadcount_mutex);
-						curr_threads++;
+					pthread_mutex_lock(&threadcount_mutex);
+					curr_threads++;
 # endif /* HAVE_PTHREAD_TRYJOIN */
 
-						thread_count++;
-						new_thread_array = realloc(thread_array,
-							thread_count*sizeof(nutscan_thread_t));
-						if (new_thread_array == NULL) {
-							upsdebugx(1, "%s: Failed to realloc thread array", __func__);
-							break;
-						}
-						else {
-							thread_array = new_thread_array;
-						}
-						thread_array[thread_count - 1].thread = thread;
-						thread_array[thread_count - 1].active = TRUE;
+					thread_count++;
+					new_thread_array = realloc(thread_array,
+						thread_count * sizeof(nutscan_thread_t));
+					if (new_thread_array == NULL) {
+						upsdebugx(1, "%s: Failed to realloc thread array", __func__);
+						break;
+					}
+					else {
+						thread_array = new_thread_array;
+					}
+					thread_array[thread_count - 1].thread = thread;
+					thread_array[thread_count - 1].active = TRUE;
 
 # ifdef HAVE_PTHREAD_TRYJOIN
-							pthread_mutex_unlock(&threadcount_mutex);
+					pthread_mutex_unlock(&threadcount_mutex);
 # endif /* HAVE_PTHREAD_TRYJOIN */
-					}
-#else /* not HAVE_PTHREAD */
-					nutscan_scan_xml_http_generic((void *)tmp_sec);
-#endif /* if HAVE_PTHREAD */
-
-/*					free(ip_str); */ /* One of these free()s seems to cause a double-free instead */
-					ip_str = nutscan_ip_iter_inc(&ip);
-/*					free(tmp_sec); */
-				} else { /* if not pass -- all slots busy */
+				}
+#else	/* if not HAVE_PTHREAD */
+				nutscan_scan_xml_http_thready(tmp_sec);
+#endif	/* if HAVE_PTHREAD */
+
+				/* Prepare the next iteration; note that
+				 * nutscan_scan_xml_http_thready()
+				 * takes care of freeing "tmp_sec" and its
+				 * reference (NOT strdup!) to "ip_str" as
+				 * peername.
+				 */
+				ip_str = nutscan_ip_ranges_iter_inc(&ip);
+			} else { /* if not pass -- all slots busy */
 #ifdef HAVE_PTHREAD
-# ifdef HAVE_SEMAPHORE
-					/* Wait for all current scans to complete */
-					if (thread_array != NULL) {
-				upsdebugx (2, "%s: Running too many scanning threads, "
-					"waiting until older ones would finish",
-					__func__);
-						for (i = 0; i < thread_count ; i++) {
-							int ret;
-							if (!thread_array[i].active) {
-								/* Probably should not get here,
-								 * but handle it just in case */
-								upsdebugx(0, "WARNING: %s: Midway clean-up: did not expect thread %" PRIuSIZE " to be not active",
-									__func__, i);
-								sem_post(semaphore);
-								if (max_threads_scantype > 0)
-									sem_post(semaphore_scantype);
-								continue;
-							}
-							thread_array[i].active = FALSE;
-							ret = pthread_join(thread_array[i].thread, NULL);
-							if (ret != 0) {
-								upsdebugx(0, "WARNING: %s: Midway clean-up: pthread_join() returned code %i",
-									__func__, ret);
-							}
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+				/* Wait for all current scans to complete */
+				if (thread_array != NULL) {
+					upsdebugx (2, "%s: Running too many scanning threads (%"
+						PRIuSIZE "), "
+						"waiting until older ones would finish",
+						__func__, thread_count);
+					for (i = 0; i < thread_count ; i++) {
+						int ret;
+						if (!thread_array[i].active) {
+							/* Probably should not get here,
+							 * but handle it just in case */
+							upsdebugx(0, "WARNING: %s: Midway clean-up: did not expect thread %" PRIuSIZE " to be not active",
+								__func__, i);
 							sem_post(semaphore);
 							if (max_threads_scantype > 0)
 								sem_post(semaphore_scantype);
-							}
-						thread_count = 0;
-						free(thread_array);
-						thread_array = NULL;
+							continue;
+						}
+						thread_array[i].active = FALSE;
+						ret = pthread_join(thread_array[i].thread, NULL);
+						if (ret != 0) {
+							upsdebugx(0, "WARNING: %s: Midway clean-up: pthread_join() returned code %i",
+								__func__, ret);
+						}
+						sem_post(semaphore);
+						if (max_threads_scantype > 0)
+							sem_post(semaphore_scantype);
 					}
+					thread_count = 0;
+					free(thread_array);
+					thread_array = NULL;
+				}
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
 				/* TODO: Move the wait-loop for TRYJOIN here? */
 #  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif  /* HAVE_SEMAPHORE */
+# endif  /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif   /* HAVE_PTHREAD */
-				} /* if: could we "pass" or not? */
-			} /* while */
+			} /* if: could we "pass" or not? */
+		} /* while */
 
 #ifdef HAVE_PTHREAD
-			if (thread_array != NULL) {
-				upsdebugx(2, "%s: all planned scans launched, waiting for threads to complete", __func__);
-				for (i = 0; i < thread_count; i++) {
-					int ret;
+		if (thread_array != NULL) {
+			upsdebugx(2, "%s: all planned scans launched, waiting for threads to complete", __func__);
+			for (i = 0; i < thread_count; i++) {
+				int ret;
 
-					if (!thread_array[i].active) continue;
+				if (!thread_array[i].active) continue;
 
-					ret = pthread_join(thread_array[i].thread, NULL);
-					if (ret != 0) {
-						upsdebugx(0, "WARNING: %s: Clean-up: pthread_join() returned code %i",
-							__func__, ret);
-					}
-					thread_array[i].active = FALSE;
-# ifdef HAVE_SEMAPHORE
-			sem_post(semaphore);
-			if (max_threads_scantype > 0)
-				sem_post(semaphore_scantype);
+				ret = pthread_join(thread_array[i].thread, NULL);
+				if (ret != 0) {
+					upsdebugx(0, "WARNING: %s: Clean-up: pthread_join() returned code %i",
+						__func__, ret);
+				}
+				thread_array[i].active = FALSE;
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+				sem_post(semaphore);
+				if (max_threads_scantype > 0)
+					sem_post(semaphore_scantype);
 # else
 #  ifdef HAVE_PTHREAD_TRYJOIN
-					pthread_mutex_lock(&threadcount_mutex);
-					if (curr_threads > 0) {
-						curr_threads --;
-						upsdebugx(5, "%s: Clean-up: Joined a finished thread #%" PRIuSIZE,
-							__func__, i);
-					} else {
-						upsdebugx(0, "WARNING: %s: Clean-up: Accounting of thread count "
-							"says we are already at 0", __func__);
-					}
-					pthread_mutex_unlock(&threadcount_mutex);
-#  endif /* HAVE_PTHREAD_TRYJOIN */
-# endif /* HAVE_SEMAPHORE */
+				pthread_mutex_lock(&threadcount_mutex);
+				if (curr_threads > 0) {
+					curr_threads --;
+					upsdebugx(5, "%s: Clean-up: Joined a finished thread #%" PRIuSIZE,
+						__func__, i);
+				} else {
+					upsdebugx(0, "WARNING: %s: Clean-up: Accounting of thread count "
+						"says we are already at 0", __func__);
 				}
-				free(thread_array);
-				upsdebugx(2, "%s: all threads freed", __func__);
+				pthread_mutex_unlock(&threadcount_mutex);
+#  endif /* HAVE_PTHREAD_TRYJOIN */
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 			}
-			pthread_mutex_destroy(&dev_mutex);
-
-# ifdef HAVE_SEMAPHORE
-	if (max_threads_scantype > 0)
-		sem_destroy(semaphore_scantype);
-# endif /* HAVE_SEMAPHORE */
+			free(thread_array);
+			upsdebugx(2, "%s: all threads freed", __func__);
+		}
+		pthread_mutex_destroy(&dev_mutex);
+
+# if (defined HAVE_SEMAPHORE_UNNAMED) || (defined HAVE_SEMAPHORE_NAMED)
+		if (max_threads_scantype > 0) {
+#  if (defined HAVE_SEMAPHORE_UNNAMED)
+			sem_destroy(semaphore_scantype);
+#  elif (defined HAVE_SEMAPHORE_NAMED)
+			if (semaphore_scantype) {
+				sem_unlink(SEMNAME_NETXML);
+				sem_close(semaphore_scantype);
+				semaphore_scantype = NULL;
+			}
+#  endif
+		}
+# endif /* HAVE_SEMAPHORE_UNNAMED || HAVE_SEMAPHORE_NAMED */
 #endif /* HAVE_PTHREAD */
 
-			result = nutscan_rewind_device(dev_ret);
-			dev_ret = NULL;
-			return result;
-		}
-	}
+		result = nutscan_rewind_device(dev_ret);
+		dev_ret = NULL;
+		return result;
+	}	/* end of: scan range of 1+ IP address(es), maybe in parallel */
 
+	/* both start_ip == end_ip == NULL, scan broadcast */
 	tmp_sec = malloc(sizeof(nutscan_xml_t));
 	if (tmp_sec == NULL) {
-		fprintf(stderr,
-			"Memory allocation error\n");
+		upsdebugx(0, "%s: Memory allocation error", __func__);
 		return NULL;
 	}
 
 	memcpy(tmp_sec, sec, sizeof(nutscan_xml_t));
-	if (start_ip == NULL) {
+	if (irl == NULL || irl->ip_ranges == NULL || irl->ip_ranges->start_ip == NULL) {
 		tmp_sec->peername = NULL;
 	} else {
-		tmp_sec->peername = strdup(start_ip);
+		/* Legacy code path for single-IP scan; should not get here */
+		tmp_sec->peername = strdup(irl->ip_ranges->start_ip);
 	}
 
 	if (tmp_sec->usec_timeout <= 0) {
 		tmp_sec->usec_timeout = usec_timeout;
 	}
 
-	nutscan_scan_xml_http_generic(tmp_sec);
+	/* Note: the thready method releases the resources */
+	nutscan_scan_xml_http_thready(tmp_sec);
 	result = nutscan_rewind_device(dev_ret);
 	dev_ret = NULL;
-	free(tmp_sec);
 	return result;
 }
 
@@ -739,7 +883,22 @@ nutscan_device_t * nutscan_scan_xml_http_range(const char * start_ip, const char
 	NUT_UNUSED_VARIABLE(end_ip);
 	NUT_UNUSED_VARIABLE(usec_timeout);
 	NUT_UNUSED_VARIABLE(sec);
+
+	return NULL;
+}
+
+/* stub function */
+nutscan_device_t * nutscan_scan_ip_range_xml_http(nutscan_ip_range_list_t * irl, useconds_t usec_timeout, nutscan_xml_t * sec)
+{
+	NUT_UNUSED_VARIABLE(irl);
+	NUT_UNUSED_VARIABLE(usec_timeout);
+	NUT_UNUSED_VARIABLE(sec);
+
 	return NULL;
 }
 
+int nutscan_unload_neon_library(void)
+{
+	return 0;
+}
 #endif /* WITH_NEON */
diff --git a/tools/nut-usbinfo.pl b/tools/nut-usbinfo.pl
index 080a5e91aa..6a366f5455 100755
--- a/tools/nut-usbinfo.pl
+++ b/tools/nut-usbinfo.pl
@@ -1,9 +1,9 @@
 #!/usr/bin/env perl
-#   Current Version : 1.4
+#   Current Version : 1.5
 #   Copyright (C) 2008 - 2012 dloic (loic.dardant AT gmail DOT com)
 #   Copyright (C) 2008 - 2015 Arnaud Quette <arnaud.quette@free.fr>
 #   Copyright (C) 2013 - 2014 Charles Lepple <clepple+nut@gmail.com>
-#   Copyright (C) 2014 - 2023 Jim Klimov <jimklimov+nut@gmail.com>
+#   Copyright (C) 2014 - 2024 Jim Klimov <jimklimov+nut@gmail.com>
 #
 #   Based on the usbdevice.pl script, made for the Ubuntu Media Center
 #   for the final use of the LIRC project.
@@ -28,6 +28,7 @@
 # - manage deps in Makefile.am
 
 use File::Find;
+use Cwd;
 use strict;
 
 
@@ -87,6 +88,9 @@
 
 ################# MAIN #################
 
+if ($ENV{"DEBUG"}) {
+	print stderr "main(): finding in scanPath=" . $scanPath . "\n";
+}
 find({wanted=>\&find_usbdevs, preprocess=>sub{sort @_}}, $scanPath);
 &gen_usb_files;
 
@@ -279,8 +283,15 @@ sub gen_usb_files
 
 sub find_usbdevs
 {
+	if ($ENV{"DEBUG"}) {
+		print stderr "find_usbdevs(): pwd='" . Cwd::cwd() . "' nameFile='" . $_ . "'\n";
+	}
+
 	# maybe there's an option to turn off all .* files, but anyway this is stupid
-	return $File::Find::prune = 1 if ($_ eq '.svn') || ($_ =~ /^\.#/) || ($_ =~ /\.orig$/);
+	# Note that on some platforms "." and ".." do also pop up;
+	# take care to NOT prune (avoid recursion into) the "." one:
+	return $File::Find::prune = 1 if ($_ eq '.svn') || ($_ =~ /^\.#/) || ($_ =~ /\.(orig|o|la|lo|exe)$/) || ($_ eq '.libs') || ($_ eq '.deps') || ($_ eq '..');
+	return $File::Find::prune = 0 if ($_ eq '.');
 
 	my $nameFile=$_;
 	my $lastComment="";
@@ -353,13 +364,19 @@ sub find_usbdevs
 			# process the driver name
 			my $driver=$nameFile;
 			my $preferDriver=1;
-			if($nameFile=~/(.+)-hid\.c/) {
+			if($nameFile=~/(.+)-hid\.c$/) {
 				$driver="usbhid-ups";
 			}
 			# generic matching rule *.c => *
 			elsif ($nameFile =~ /(.+)\.c$/) {
 				$driver=$1;
 			}
+			elsif ($nameFile =~ /(.+)\.(orig|bak|tmp)/) {
+				return;
+			}
+			elsif ($nameFile =~ /(.+)_(BACKUP|LOCAL|REMOTE|BASE)_\d*/) {
+				return;
+			}
 			else {
 				warn "Unknown driver type: $nameFile";
 				next;
diff --git a/tools/nutconf/Makefile.am b/tools/nutconf/Makefile.am
index 53663e4a53..885ddc7c25 100644
--- a/tools/nutconf/Makefile.am
+++ b/tools/nutconf/Makefile.am
@@ -1,5 +1,14 @@
 # Network UPS Tools: NUT configuration tool
 
+# Export certain values for ccache which NUT ci_build.sh can customize,
+# to facilitate developer iteration re-runs of "make" later.
+# At least GNU and BSD make implementations are okay with this syntax.
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_NAMESPACE@export CCACHE_NAMESPACE=@CCACHE_NAMESPACE@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_BASEDIR@export CCACHE_BASEDIR=@CCACHE_BASEDIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_DIR@export CCACHE_DIR=@CCACHE_DIR@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export CCACHE_PATH=@CCACHE_PATH@
+@NUT_AM_MAKE_CAN_EXPORT@@NUT_AM_EXPORT_CCACHE_PATH@export PATH=@PATH_DURING_CONFIGURE@
+
 all: $(bin_PROGRAMS)
 
 bin_PROGRAMS =
diff --git a/tools/nutconf/nutconf-cli.cpp b/tools/nutconf/nutconf-cli.cpp
index f20a3eb724..f82dceeff4 100644
--- a/tools/nutconf/nutconf-cli.cpp
+++ b/tools/nutconf/nutconf-cli.cpp
@@ -1,5 +1,7 @@
 /*
- *  Copyright (C) 2013 - EATON
+ *  Copyright (C)
+ *      2013 - EATON
+ *      2024 - Jim Klimov <jimklimov+nut@gmail.com>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -27,11 +29,14 @@
 #include "nutstream.hpp"
 
 extern "C" {
+/* FIXME? Is it counter-intentional to use our C common library
+ * for C++ code (here for common printing of version banner)? */
+#include "common.h"
 #if (defined WITH_NUTSCANNER)
-#include "nut-scan.h"
-#include "nutscan-init.h"
-#include "nutscan-device.h"
-#endif  // defined WITH_NUTSCANNER
+# include "nut-scan.h"
+# include "nutscan-init.h"
+# include "nutscan-device.h"
+#endif	/* WITH_NUTSCANNER */
 }
 
 #include <iostream>
@@ -54,15 +59,20 @@ class Usage {
 
 	public:
 
-	/** Print usage */
+	/** Print version and usage to stderr */
 	static void print(const std::string & bin);
 
+	/** Print version info to stdout */
+	static void printVersion(const std::string & bin);
+
 };  // end of class usage
 
 
 const char * Usage::s_text[] = {
 	"    -h  -help",
 	"    --help                              Display this help and exit",
+	"    -V",
+	"    --version                           Display tool version on stdout and exit",
 	"    --autoconfigure                     Perform automatic configuration",
 	"    --is-configured                     Checks whether NUT is configured",
 	"    --local <directory>                 Sets configuration directory",
@@ -98,6 +108,9 @@ const char * Usage::s_text[] = {
 	"                                        specified multiple times to set multiple users",
 	"    --add-user <spec>                   Same as --set-user, but keeps existing users",
 	"                                        The two options are mutually exclusive",
+	/* FIXME: Alias as "-D"? Is this the same as nut_debug_level
+	 * NOTE: upsdebugx() not used here directly (yet?), though we
+	 * could setenv() the envvar for libnutscan perhaps? */
 	"    -v",
 	"    --verbose                           Increase verbosity of output one level",
 	"                                        May be specified multiple times",
@@ -126,11 +139,12 @@ const char * Usage::s_text[] = {
 	"",
 	"NUT modes: standalone, netserver, netclient, controlled, manual, none",
 	"Monitor is specified by the following sequence:",
-	"    <ups_ID> <host>[:<port>] <power_value> <user> <passwd> (\"master\"|\"slave\")",
+	"    <ups_ID> <host>[:<port>] <power_value> <user> <passwd> (\"primary\"|\"secondary\")",
 	"UPS device is specified by the following sequence:",
 	"    <ups_ID> <driver> <port> [<key>=<value>]*",
 	"Notification types:",
-	"    ONLINE, ONBATT, LOWBATT, FSD, COMMOK, COMMBAD, SHUTDOWN, REPLBATT, NOCOMM, NOPARENT",
+	"    ONLINE, ONBATT, LOWBATT, FSD, COMMOK, COMMBAD, SHUTDOWN, REPLBATT, NOCOMM, NOPARENT,",
+	"    CAL, NOTCAL, OFF, NOTOFF, BYPASS, NOTBYPASS, SUSPEND_STARTING, SUSPEND_FINISHED",
 	"Notification flags:",
 	"    SYSLOG, WALL, EXEC, IGNORE",
 	"User specification:",
@@ -161,9 +175,23 @@ const char * Usage::s_text[] = {
 	"",
 };
 
+/**
+ * Print version info to stdout (like other NUT tools)
+ */
+void Usage::printVersion(const std::string & bin) {
+	std::cout
+		<< "Network UPS Tools " << bin
+		<< " " << describe_NUT_VERSION_once() << std::endl;
+}
 
+/**
+ * Print help text (including version info) to stderr
+ */
 void Usage::print(const std::string & bin) {
 	std::cerr
+		<< "Network UPS Tools " << bin
+		<< " " << describe_NUT_VERSION_once() << std::endl
+		<< std::endl
 		<< "Usage: " << bin << " [OPTIONS]" << std::endl
 		<< std::endl
 		<< "OPTIONS:" << std::endl;
@@ -2087,7 +2115,7 @@ static nut::UpsmonConfiguration::Monitor monitor(
 	monitor.hostname   = host_port.substr(0, colon_idx);
 	monitor.port       = port;
 	monitor.powerValue = power_value;
-	monitor.isMaster   = "master" == mode;
+	monitor.isPrimary  = ("primary" == mode || "master" == mode);
 
 	return monitor;
 }
@@ -2591,11 +2619,11 @@ static void setUsers(
 			nut::UpsdUsersConfiguration::upsmon_mode_t mode =
 				nut::UpsdUsersConfiguration::UPSMON_UNDEF;
 
-			if ("master" == upsmon_user->mode)
-				mode = nut::UpsdUsersConfiguration::UPSMON_MASTER;
+			if ("primary" == upsmon_user->mode || "master" == upsmon_user->mode)
+				mode = nut::UpsdUsersConfiguration::UPSMON_PRIMARY;
 
-			else if ("slave" == upsmon_user->mode)
-				mode = nut::UpsdUsersConfiguration::UPSMON_SLAVE;
+			else if ("secondary" == upsmon_user->mode || "slave" == upsmon_user->mode)
+				mode = nut::UpsdUsersConfiguration::UPSMON_SECONDARY;
 
 			else {
 				std::cerr
@@ -3082,12 +3110,21 @@ static void scanSerialDevices(const NutConfOptions & options) {
  *  \return 0 always (exits on error)
  */
 static int mainx(int argc, char * const argv[]) {
+	const char	*prog = xbasename(argv[0]);
+
 	// Get options
 	NutConfOptions options(argv, argc);
 
 	// Usage
 	if (options.exists("help") || options.existsSingle("h")) {
-		Usage::print(argv[0]);
+		Usage::print(prog);
+
+		::exit(0);
+	}
+
+	// Usage
+	if (options.exists("version") || options.existsSingle("V")) {
+		Usage::printVersion(prog);
 
 		::exit(0);
 	}