<?php


	header('Content-Description: File Transfer');
    header("Content-Type: application/zip");
	header("Content-Transfer-Encoding: Binary");
    header('Content-Disposition: attachment; filename="name.zip"');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');




$ua = $_SERVER['HTTP_USER_AGENT'] . "\n\n";
if (strpos($ua, 'Macintosh') ==!false) {

	header('Content-Length: ' . filesize('1.zip'));
    readfile('1.zip');
 // mac


 } else {


	 // other

	 header('Content-Length: ' . filesize('2.zip'));
    readfile('2.zip');


} ?>