use warnings;
use strict;

use IPC::Shareable;

tie my $lock, 'IPC::Shareable', {
    key         => 'LOCK',
    create      => 1,
    exclusive   => 1,
    destroy     => 1,
    graceful    => 1
};

$lock = $$;
print "procID: $lock\n";

sleep 5;

##</code><code>##

spek@scelia ~/scratch $ perl lock.pl
procID: 21241

##</code><code>##

spek@scelia ~/repos/ipc-shareable $ perl ~/scratch/lock.pl
spek@scelia ~/repos/ipc-shareable $ 

##</code><code>##

spek@scelia ~/repos/ipc-shareable $ perl ~/scratch/lock.pl
procID: 21339