1#!/bin/sh 2# Ensure tail -F distinguishes output with the correct headers 3# Between coreutils 7.5 and 8.23 inclusive, 'tail -F ...' would 4# not output headers for or created/renamed files in certain cases. 5 6# Copyright (C) 2015-2023 Free Software Foundation, Inc. 7 8# This program is free software: you can redistribute it and/or modify 9# it under the terms of the GNU General Public License as published by 10# the Free Software Foundation, either version 3 of the License, or 11# (at your option) any later version. 12 13# This program is distributed in the hope that it will be useful, 14# but WITHOUT ANY WARRANTY; without even the implied warranty of 15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16# GNU General Public License for more details. 17 18# You should have received a copy of the GNU General Public License 19# along with this program. If not, see <https://www.gnu.org/licenses/>. 20 21. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src 22print_ver_ tail 23 24check_tail_output() 25{ 26 local delay="$1" 27 grep "$tail_re" out || 28 { sleep $delay; return 1; } 29} 30 31# Terminate any background tail process 32cleanup_() { kill $pid 2>/dev/null && wait $pid; } 33 34# Speedup the non inotify case 35fastpoll='-s.1 --max-unchanged-stats=1' 36 37for mode in '' '---disable-inotify'; do 38 rm -f a b out 39 40 tail $mode -F $fastpoll a b > out 2>&1 & pid=$! 41 42 # Wait up to 12.7s for tail to start. 43 tail_re="cannot open 'b'" retry_delay_ check_tail_output .1 7 || 44 { cat out; fail=1; } 45 46 echo x > a 47 # Wait up to 12.7s for a's header to appear in the output: 48 tail_re='==> a <==' retry_delay_ check_tail_output .1 7 || 49 { echo "$0: a: unexpected delay?"; cat out; fail=1; } 50 51 echo y > b 52 # Wait up to 12.7s for b's header to appear in the output: 53 tail_re='==> b <==' retry_delay_ check_tail_output .1 7 || 54 { echo "$0: b: unexpected delay?"; cat out; fail=1; } 55 56 cleanup_ 57done 58 59Exit $fail 60