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

   1 #!/bin/sh
   2 # demonstrate that tail -F works for currently missing dirs
   3 # Before coreutils-8.6, tail -F missing/file would not
   4 # notice any subsequent availability of the missing/file.
   5
   6 # Copyright (C) 2010-2013 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 debug='---disable-inotify'
  25 debug=
  26 tail $debug -F -s.1 missing/file > out 2>&1 & pid=$!
  27
  28 check_tail_output()
  29 {
  30   local delay="$1"
  31   grep "$tail_re" out > /dev/null ||
  32     { sleep $delay; return 1; }
  33 }
  34
  35 # Wait up to 6.3s for tail to start with diagnostic:
  36 # tail: cannot open 'missing/file' for reading: No such file or directory
  37 tail_re='cannot open' retry_delay_ check_tail_output .1 7 || fail=1
  38
  39 mkdir missing || fail=1
  40 (cd missing && echo x > file)
  41
  42 # Wait up to 6.3s for this to appear in the output:
  43 # "tail: '...' has appeared;  following end of new file"
  44 tail_re='has appeared' retry_delay_ check_tail_output .1 7 ||
  45   { echo "$0: file: unexpected delay?"; cat out; fail=1; }
  46
  47 kill -HUP $pid
  48
  49 cleanup()
  50 {
  51   local delay="$1"
  52   rm -rf missing ||
  53     { sleep $delay; return 1; }
  54 }
  55
  56 # Try repeatedly to remove the temporary directory.
  57 # This is normally unnecessary, because the containing directory will
  58 # be removed by code from init.sh.  However, when this particular test
  59 # is run on an NFS-mounted volume, sometimes init.sh's cleanup code
  60 # fails because the directory is not yet really empty, perhaps because
  61 # the tail process (reading missing/file) is not yet killed.
  62 retry_delay_ cleanup .1 6
  63
  64 Exit $fail