src/nohup.sh

   1 #!/bin/sh
   2 # nohup -- run a command immume to hangups, with output to a non-tty
   3 # Copyright (C) 1991, 1997, 1999 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 Foundation,
  17 # Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  18
  19 # Written by David MacKenzie <djm@gnu.ai.mit.edu>.
  20
  21 usage="Usage: $0 COMMAND [ARG]...
  22   or:  $0 OPTION"
  23
  24 usage_try="
  25 Try \`$0 --help' for more information."
  26
  27 usage_help="Run COMMAND, ignoring hangup signals.
  28
  29   --help      display this help and exit
  30   --version   output version information and exit
  31
  32 Report bugs to <sh-utils-bugs@gnu.org>."
  33
  34 if [ $# -eq 0 ]; then
  35   echo >&2 "$usage"
  36   echo >&2 "$usage_try"
  37   exit 1
  38 fi
  39
  40 case $# in
  41   1 )
  42     case "z${1}" in
  43       z--help )
  44          echo "$usage"; echo "$usage_help"; exit 0 ;;
  45       z--version )
  46          echo "nohup (@GNU_PACKAGE@) @VERSION@"; exit 0 ;;
  47       * ) ;;
  48     esac
  49     ;;
  50   * ) ;;
  51 esac
  52
  53 # Make sure we get GNU nice, if possible; also allow
  54 # it to be somewhere else in PATH if not installed yet.
  55 # But do not modify PATH itself.
  56 IFS="${IFS=      }"; save_ifs="$IFS"; IFS=":"
  57 nicepath="@bindir@:$PATH"
  58 niceprog="nice"
  59 for nicedir in $nicepath; do
  60   test -z "$nicedir" && nicedir="."
  61   if test -x "$nicedir/nice"; then
  62     niceprog="$nicedir/nice"
  63     break
  64   fi
  65 done
  66 IFS="$save_ifs"
  67
  68 trap "" 1
  69 oldmask=`umask`; umask 077
  70 # Only redirect the output if the user didn't already do it.
  71 if [ -t 1 ]; then
  72   # If we cannot write to the current directory, use the home directory.
  73   if cat /dev/null >> nohup.out; then
  74     echo "nohup: appending output to \`nohup.out'" 2>&1
  75     umask $oldmask
  76     exec "$niceprog" -5 -- "$@" >> nohup.out 2>&1
  77   else
  78     cat /dev/null >> $HOME/nohup.out
  79     echo "nohup: appending output to \`$HOME/nohup.out'" 2>&1
  80     umask $oldmask
  81     exec "$niceprog" -5 -- "$@" >> $HOME/nohup.out 2>&1
  82   fi
  83 else
  84   umask $oldmask
  85   exec "$niceprog" -5 -- "$@"
  86 fi