filt

   1 #!/usr/bin/env bash
   2
   3 #=======================================================================
   4 # filt
   5 # File ID: aad4fde6-02e6-11de-acfb-000475e441b9
   6 # Kjører ei fil ($2 osv) gjennom et filter som spesifiseres som $1.
   7 # License: GNU General Public License version 2 or later.
   8 #=======================================================================
   9
  10 use_lock=1
  11 test "$1" = "-u" && { use_lock=0; shift; }
  12 cmd=$1
  13 retval=0
  14 shift
  15 for ff in "$@"; do
  16     if [ -f "$ff" ]; then
  17         # cp -p $ff $ff.filt-bck
  18         if test "$use_lock" = "1"; then
  19             lock_wait=0
  20             until mkdir "$ff.lock"; do
  21                 echo filt: $ff: Waiting for lock... >&2
  22                 lock_wait=1
  23                 sleep 1
  24             done
  25             test "$lock_wait" = "1" && { echo filt: $ff: Obtained lock >&2; }
  26         fi
  27         cat "$ff" | $cmd >"$ff.filt.tmp"
  28         retval=$[$retval | $?];
  29         chmod --reference "$ff" "$ff.filt.tmp"
  30         mv "$ff.filt.tmp" "$ff"
  31         if test "$use_lock" = "1"; then
  32             rmdir "$ff.lock" || { echo filt: $ff.lock: Lockdir unexpectedly disappeared >&2; }
  33         fi
  34     else
  35         echo filt: $ff: Not a regular file >&2
  36         retval=$[$retval | 1];
  37     fi
  38 done
  39 exit $retval