Add crosscompile job to CI. #3

	name: Continuous Integration

	on: [push, pull_request]

	jobs:

	build:
	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3

	- name: Install pcap
	run: sudo apt install libpcap-dev

	- name: Set up Go
	uses: actions/setup-go@v4
	with:
	go-version: '1.20'

	- name: Build
	run: go build -v ipxbox.go

	crosscompile:
	strategy:
	matrix:
	goarch: [386, amd64, arm64]
	goos: [darwin, freebsd, linux, windows]

	runs-on: ubuntu-latest
	steps:
	- uses: actions/checkout@v3

	- name: Set up Go
	uses: actions/setup-go@v4
	with:
	go-version: '1.20'

	- name: Build
	run: go build -tags nopcap -v ipxbox.go
	env:
	GOARCH: ${{ matrix.goarch }}
	GOOS: ${{ matrix.goos }}

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