diff --git a/gh-md-toc b/gh-md-toc
index 9926e8a..0122c80 100755
--- a/gh-md-toc
+++ b/gh-md-toc
@@ -217,10 +217,10 @@ gh_toc_get_filename() {
 # Options hendlers
 #
 gh_toc_app() {
-    local app_name=$(basename $0)
     local need_replace="no"
 
     if [ "$1" = '--help' ] || [ $# -eq 0 ] ; then
+        local app_name=$(basename "$0")
         echo "GitHub TOC generator ($app_name): $gh_toc_version"
         echo ""
         echo "Usage:"