I have a simple program strait out of the text book: 
#!/usr/bin/env perl
use strict;
use warnings;

open(FH, "+< rotator_lock")                or die "can't open: $!";
flock(FH, 2)                        or die "can't flock: $!";
# update file, then...
sleep(120);
close(FH)                           or die "can't close: $!";

[download]
However I am able to start multiple instances of this application without any errors or limitations. I was under impression that flock would prevent this app from running multiple instances. Can someone advise what I am doing wrong here? Thanks in advance

In reply to SOLVED [flock on Ubuntu 9.10] by poctob

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