Add some basic file locking to prevent parallel invocations of the script: only one...

git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/simgrid/simgrid/trunk@6013 48e7efb5-ca39-0410-a469-dd3cf9ba447f

diff --git a/tools/sg_unit_extractor.pl b/tools/sg_unit_extractor.pl
index 4e233f1..37b7025 100755 (executable)
--- a/tools/sg_unit_extractor.pl
+++ b/tools/sg_unit_extractor.pl
@@ -1,6 +1,13 @@
 #! /usr/bin/perl
 
 use strict;
+use Fcntl ':flock';
+
+open SELF, "< $0" or die "Cannot open the lock file";
+if (!flock SELF, LOCK_EX | LOCK_NB) {
+    print STDERR "sg_unit_extractor already running. Cancelling...\n";
+    exit;
+}
 
 my $progname="sg_unit_extractor";
 # Get the args