tests/tail-2/F-vs-rename.sh

   1 #!/bin/sh
   2 # Demonstrate that tail -F works when renaming the tailed files.
   3 # Between coreutils 7.5 and 8.2 inclusive, 'tail -F a b' would
   4 # stop tracking additions to b after 'mv a b'.
   5
   6 # Copyright (C) 2009-2016 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 <http://www.gnu.org/licenses/>.
  20
  21 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  22 print_ver_ tail
  23
  24 check_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
  32 cleanup_() { kill $pid 2>/dev/null && wait $pid; }
  33
  34 # Speedup the non inotify case
  35 fastpoll='-s.1 --max-unchanged-stats=1'
  36
  37 for mode in '' '---disable-inotify'; do
  38   rm -f a b out
  39   touch a b || framework_failure_
  40
  41   tail $mode -F $fastpoll a b > out 2>&1 & pid=$!
  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   # Wait 12.7s for this diagnostic:
  50   # tail: 'a' has become inaccessible: No such file or directory
  51   tail_re='inaccessible' retry_delay_ check_tail_output .1 7 ||
  52     { cat out; fail=1; }
  53
  54   echo x > a
  55   # Wait up to 12.7s for this to appear in the output:
  56   # "tail: '...' has appeared;  following new file"
  57   tail_re='has appeared' retry_delay_ check_tail_output .1 7 ||
  58     { echo "$0: a: unexpected delay?"; cat out; fail=1; }
  59
  60   echo y >> b
  61   # Wait up to 12.7s for "y" to appear in the output:
  62   tail_f_vs_rename_2() {
  63     local delay="$1"
  64     tr '\n' @ < out | grep '@@==> b <==@y@$' > /dev/null ||
  65       { sleep $delay; return 1; }
  66   }
  67   retry_delay_ tail_f_vs_rename_2 .1 7 ||
  68     { echo "$0: b: unexpected delay?"; cat out; fail=1; }
  69
  70   echo z >> a
  71   # Wait up to 12.7s for "z" to appear in the output:
  72   tail_f_vs_rename_3() {
  73     local delay="$1"
  74     tr '\n' @ < out | grep '@@==> a <==@z@$' > /dev/null ||
  75       { sleep $delay; return 1; }
  76   }
  77   retry_delay_ tail_f_vs_rename_3 .1 7 ||
  78     { echo "$0: a: unexpected delay?"; cat out; fail=1; }
  79
  80   cleanup_
  81 done
  82
  83 Exit $fail