#! /bin/sh # interlock - wrap program invocation in lock to allow # parallel builds to work. # Written by Tom Tromey <tromey@cygnus.com>, Aug 10 1996 # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2, or (at your option) # any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. # Usage: # interlock lock-dir-name program args-to-program... dirname="$1" program="$2" shift shift while (mkdir $dirname > /dev/null 2>&1 && exit 1 || exit 0); do # Wait a bit. sleep 1 done # Race condition here: if interrupted after the loop but before this # trap, the lock can be left around. trap "rmdir $dirname > /dev/null 2>&1" 1 2 3 15 # We have the lock, so run the program. $program ${1+"$@"} ret=$? # Release the lock. rmdir $dirname > /dev/null 2>&1 exit $ret