Update documentation on I/O #1413

	name: linux

	on: [push, pull_request]

	jobs:
	test:
	runs-on: ubuntu-latest
	strategy:
	fail-fast: false
	matrix:
	cvmfs_base: ['sft.cern.ch/lcg/views']
	ENVIRONMENT: ['dev3/latest/x86_64-centos7-gcc11-opt']
	steps:
	- uses: actions/checkout@v2
	- uses: cvmfs-contrib/github-action-cvmfs@v2
	- name: Start container
	run: \|
	docker run -it --name CI_container -v ${GITHUB_WORKSPACE}:/Package -v /cvmfs:/cvmfs:shared -d ghcr.io/aidasoft/centos7:latest /bin/bash
	- name: CMake Configure
	run: \|
	docker exec CI_container /bin/bash -c 'cd Package;\
	mkdir -p build install;\
	source /cvmfs/${{ matrix.cvmfs_base }}/${{ matrix.ENVIRONMENT }}/setup.sh;\
	cd build;\
	cmake -DCMAKE_INSTALL_PREFIX=../install -DCMAKE_CXX_STANDARD=20 -DCMAKE_CXX_FLAGS=" -fdiagnostics-color=always " -G Ninja ..;'
	- name: Compile
	run: \|
	docker exec CI_container /bin/bash -c 'cd ./Package;\
	source /cvmfs/${{ matrix.cvmfs_base }}/${{ matrix.ENVIRONMENT }}/setup.sh;\
	cd build;\
	ninja -k0;'
	- name: Test
	run: \|
	docker exec CI_container /bin/bash -c 'cd ./Package;\
	source /cvmfs/${{ matrix.cvmfs_base }}/${{ matrix.ENVIRONMENT }}/setup.sh;\
	cd build;\
	ninja -k0 && ctest --output-on-failure;'
	- name: Install
	run: \|
	docker exec CI_container /bin/bash -c 'cd ./Package;\
	source /cvmfs/${{ matrix.cvmfs_base }}/${{ matrix.ENVIRONMENT }}/setup.sh;\
	cd build;\
	ninja -k0 install;'

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