zless.in

   1 #!/bin/sh
   2
   3 # Copyright (C) 1998, 2002, 2006-2007, 2010-2024 Free Software Foundation, Inc.
   4
   5 # This program is free software; you can redistribute it and/or modify
   6 # it under the terms of the GNU General Public License as published by
   7 # the Free Software Foundation; either version 3 of the License, or
   8 # (at your option) any later version.
   9
  10 # This program is distributed in the hope that it will be useful,
  11 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 # GNU General Public License for more details.
  14
  15 # You should have received a copy of the GNU General Public License
  16 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  17
  18 version="zless (gzip) @VERSION@
  19 Copyright (C) 2024 Free Software Foundation, Inc.
  20 This is free software.  You may redistribute copies of it under the terms of
  21 the GNU General Public License <https://www.gnu.org/licenses/gpl.html>.
  22 There is NO WARRANTY, to the extent permitted by law.
  23
  24 Written by Paul Eggert."
  25
  26 usage="Usage: $0 [OPTION]... [FILE]...
  27 Like 'less', but operate on the uncompressed contents of any compressed FILEs.
  28
  29 Options are the same as for 'less'.
  30
  31 Report bugs to <bug-gzip@gnu.org>."
  32
  33 case $1 in
  34 --help)      printf '%s\n' "$usage"   || exit 1; exit;;
  35 --version)   printf '%s\n' "$version" || exit 1; exit;;
  36 esac
  37
  38 if test "${LESSMETACHARS+set}" != set; then
  39   # Work around a bug in less 394 and earlier;
  40   # it mishandles the metacharacters '$%=~'.
  41   space=' '
  42   tab=' '
  43   newline='
  44 '
  45   LESSMETACHARS="$space$tab$newline'"';*?"()<>[|&^`#\$%=~'
  46   export LESSMETACHARS
  47 fi
  48
  49 less_version=`less -V 2>/dev/null`
  50 case $less_version in
  51 less' '45[1-9]* | \
  52 less' '4[6-9][0-9]* | \
  53 less' '[5-9][0-9][0-9]* | \
  54 less' '[1-9][0-9][0-9][0-9]*)
  55    check_exit_status='|';;
  56 *) check_exit_status='';;
  57 esac
  58 case $less_version in
  59 less' '429* | \
  60 less' '4[3-9][0-9]* | \
  61 less' '[5-9][0-9][0-9]* | \
  62 less' '[1-9][0-9][0-9][0-9]*)
  63    use_input_pipe_on_stdin='-';;
  64 *) use_input_pipe_on_stdin='';;
  65 esac
  66 case $less_version in
  67 less' '623* | \
  68 less' '62[4-9]* | \
  69 less' '6[3-9][0-9]* | \
  70 less' '[7-9][0-9][0-9]* | \
  71 less' '[1-9][0-9][0-9][0-9]*)
  72    show_preproc_error='--show-preproc-error';;
  73 *) show_preproc_error='';;
  74 esac
  75
  76 LESSOPEN="|$check_exit_status${use_input_pipe_on_stdin}'gzip' -cdfq -- %s"
  77 export LESSOPEN
  78
  79 exec less $show_preproc_error "$@"