Filelock

gistfile1.aw

<?php
$file = dirname( __FILE__ ).'/lock.txt';
$lock = file_exists($file);
if($lock) $lock = file_get_contents($file);
if($lock && $lock != 'unlocked' && ((time() - $lock) < 120))
  die('Het scriptje is al bezig! Wacht '.(120 - (time() - $lock)).'s.');
else file_put_contents($file, time());

echo 'ZWARE OPERATIE';

file_put_contents('lock.txt', 'unlocked');