PHP Externe Dateigröße auslesen

<?php
function urlfilesize($url,$thereturn) {
if (substr($url,0,4)=='http') {
$x = array_change_key_case(get_headers($url, 1),CASE_LOWER);
$x = $x['content-length'];
            }
else { $x = @filesize($url); }
if (!$thereturn) { return $x ; }
elseif($thereturn == 'mb') { return round($x / (1024*1024),2) ; }
elseif($thereturn == 'kb') { return round($x / (1024),2) ; }
}

?>

The example :
<?php
echo urlfilesize('http://www.tayo.fr/remote-irc-tutoriel.php','mb')

?>

<?php
function getSizeFile($url) {

    if (substr($url,0,4)=='http') {

        $x = array_change_key_case(get_headers($url, 1),CASE_LOWER);

        if ( strcasecmp($x[0], 'HTTP/1.1 200 OK') != 0 ) {

        	$x = $x['content-length'][1];

        } else {

            $x = $x['content-length'];

        }

    } else { $x = @filesize($url); }

    return $x;

}

echo getSizeFile("http://kernel.org/pub/linux/kernel/v2.6/linux-2.6.28.8.tar.bz2");

?>