1#!/bin/sh 2# Demonstrate that tail -f works when renaming the tailed files. 3# Between coreutils 7.5 and 8.23 inclusive, 'tail -f a' would 4# stop tracking additions to b after 'mv a b'. 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 out 39 touch a || framework_failure_ 40 41 tail $mode $fastpoll -f a > out 2>&1 & pid=$! 42 43 # Wait up to 12.7s for tail to start. 44 echo x > a 45 tail_re='^x$' retry_delay_ check_tail_output .1 7 || { cat out; fail=1; } 46 47 mv a b || framework_failure_ 48 49 echo y >> b 50 # Wait up to 12.7s for "y" to appear in the output: 51 tail_re='^y$' retry_delay_ check_tail_output .1 7 || { cat out; fail=1; } 52 53 cleanup_ 54done 55 56Exit $fail 57