src/nohup.sh

   1 #!/bin/sh
   2 # nohup -- run a command immume to hangups, with output to a non-tty
   3 # Copyright (C) 1991 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 2, or (at your option)
   8 # 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, write to the Free Software
  17 # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 # Written by David MacKenzie <djm@gnu.ai.mit.edu>.
  20
  21 # Make sure we get GNU nice, if possible; also allow
  22 # it to be somewhere else in PATH if not installed yet.
  23 PATH=@bindir@:$PATH
  24
  25 usage="Usage: $0 COMMAND [ARG]...
  26   or:  $0 OPTION"
  27
  28 usage_try="
  29 Try \`$0 --help' for more information."
  30
  31 usage_help="Run COMMAND, ignoring hangup signals.
  32
  33   --help      display this help and exit
  34   --version   output version information and exit"
  35
  36 if [ $# -eq 0 ]; then
  37   echo >&2 "$usage"
  38   echo >&2 "$usage_try"
  39   exit 1
  40 fi
  41
  42 case $# in
  43   1 )
  44     case "z${1}" in
  45       z--help )
  46          echo "$usage"; echo "$usage_help"; exit 0 ;;
  47       z--version )
  48          echo "nohup - @PKG_VERSION@"; exit 0 ;;
  49       * ) ;;
  50     esac
  51     ;;
  52   * ) ;;
  53 esac
  54
  55 trap "" 1
  56 oldmask=`umask`; umask 077
  57 # Only redirect the output if the user didn't already do it.
  58 if [ -t 1 ]; then
  59   # If we cannot write to the current directory, use the home directory.
  60   if cat /dev/null >> nohup.out; then
  61     echo "nohup: appending output to \`nohup.out'" 2>&1
  62     umask $oldmask
  63     exec nice -5 -- "$@" >> nohup.out 2>&1
  64   else
  65     cat /dev/null >> $HOME/nohup.out
  66     echo "nohup: appending output to \`$HOME/nohup.out'" 2>&1
  67     umask $oldmask
  68     exec nice -5 -- "$@" >> $HOME/nohup.out 2>&1
  69   fi
  70 else
  71   umask $oldmask
  72   exec nice -5 -- "$@"
  73 fi