transfer file to page

file.transfer.php

<?

$expire=180;
$showname = "testfile.tgz"; 
$file = '/var/www/snippet/index.html';
$length = filesize($file);

/* the file type is accroding to the mime type, not concern on file name */
header('Content-Description: File Transfer');
header('Content-Type: text/html'); 
header('Content-Disposition: attachment; filename='.$showname);
header('Content-Transfer-Encoding: binary');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: ' . $length);

ob_clean();
flush();
readfile($file);
exit;