CI: upgrade actions/checkout to v4. #28

	name: CI
	on:
	- push
	- pull_request
	jobs:
	main:
	strategy:
	matrix:
	os:
	- ubuntu-20.04
	- ubuntu-22.04
	cc:
	- gcc
	- clang
	runs-on: ${{matrix.os}}
	steps:
	- uses: actions/checkout@v4
	- name: set up APT
	run: \|
	printf 'Apt::Install-Recommends "false";\n' \| sudo tee -a /etc/apt/apt.conf
	sudo apt-get update
	- name: check C compiler version
	run:
	${{matrix.cc}} --version
	- name: build
	run:
	make CC=${{matrix.cc}}
	- name: build docs
	run:
	make -C doc
	- name: checks docs
	run:
	make -C doc check
	- name: check what /bin/sh points to
	run:
	readlink -f /bin/sh
	- name: run tests
	run: \|
	perl -E 'say $SIG{PIPE} // DEFAULT'
	make test
	- name: install
	run: \|
	make install PREFIX=~/.local
	- name: clean
	run: \|
	make clean
	- name: run post-install tests
	run: \|
	make test-installed
	cd /
	shellcat --version
	shellcat --help
	export MANPATH=~/.local/share/man MANWIDTH=80
	man 1 shellcat \| grep -A 10 -w SHELLCAT
	- name: run cppcheck
	if: matrix.cc == 'gcc'
	run: \|
	sudo apt-get install cppcheck
	cppcheck --error-exitcode=1 *.c

	# vim:ts=2 sts=2 sw=2 et

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