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 along
  16 # with this program; if not, write to the Free Software Foundation, Inc.,
  17 # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18
  19 version="zless (gzip) @VERSION@
  20 Copyright (C) 2024 Free Software Foundation, Inc.
  21 This is free software.  You may redistribute copies of it under the terms of
  22 the GNU General Public License <https://www.gnu.org/licenses/gpl.html>.
  23 There is NO WARRANTY, to the extent permitted by law.
  24
  25 Written by Paul Eggert."
  26
  27 usage="Usage: $0 [OPTION]... [FILE]...
  28 Like 'less', but operate on the uncompressed contents of any compressed FILEs.
  29
  30 Options are the same as for 'less'.
  31
  32 Report bugs to <bug-gzip@gnu.org>."
  33
  34 case $1 in
  35 --help)      printf '%s\n' "$usage"   || exit 1; exit;;
  36 --version)   printf '%s\n' "$version" || exit 1; exit;;
  37 esac
  38
  39 if test "${LESSMETACHARS+set}" != set; then
  40   # Work around a bug in less 394 and earlier;
  41   # it mishandles the metacharacters '$%=~'.
  42   space=' '
  43   tab=' '
  44   newline='
  45 '
  46   LESSMETACHARS="$space$tab$newline'"';*?"()<>[|&^`#\$%=~'
  47   export LESSMETACHARS
  48 fi
  49
  50 less_version=`less -V 2>/dev/null`
  51 case $less_version in
  52 less' '45[1-9]* | \
  53 less' '4[6-9][0-9]* | \
  54 less' '[5-9][0-9][0-9]* | \
  55 less' '[1-9][0-9][0-9][0-9]*)
  56    check_exit_status='|';;
  57 *) check_exit_status='';;
  58 esac
  59 case $less_version in
  60 less' '429* | \
  61 less' '4[3-9][0-9]* | \
  62 less' '[5-9][0-9][0-9]* | \
  63 less' '[1-9][0-9][0-9][0-9]*)
  64    use_input_pipe_on_stdin='-';;
  65 *) use_input_pipe_on_stdin='';;
  66 esac
  67 case $less_version in
  68 less' '623* | \
  69 less' '62[4-9]* | \
  70 less' '6[3-9][0-9]* | \
  71 less' '[7-9][0-9][0-9]* | \
  72 less' '[1-9][0-9][0-9][0-9]*)
  73    show_preproc_error='--show-preproc-error';;
  74 *) show_preproc_error='';;
  75 esac
  76
  77 LESSOPEN="|$check_exit_status${use_input_pipe_on_stdin}'gzip' -cdfq -- %s"
  78 export LESSOPEN
  79
  80 exec less $show_preproc_error "$@"