web应用程序- PHP cURL下载不工作时，从浏览器调用

我想要一个php脚本，我可以从浏览器访问，该脚本将下载文件到我的远程服务器(不是我的计算机)。这是完整的代码，我从浏览器调用localhost/download.php，但它不起作用(在网络管理器中，我看到正在下载的东西，但在项目文件夹中我找不到它):

<?  
    function download($url, $referer, $name)
    {
        $path = $name.'.mp3';
        $fp = fopen($path, 'w');
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_FILE, $fp);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_HEADER, false);
        curl_setopt($ch, CURLOPT_HTTPHEADER, array(
                    'User-Agent: Mozilla/5.0 (X11; Ubuntu; Linux i686; rv:13.5) Gecko/20100101 Firefox/13.4.9'r'n',
                    "Referer: $referer" 
        ));
        $data = curl_exec($ch);
        curl_close($ch);
        fwrite($fp, $data);
        fclose($fp);
    }
    echo 'Please wait it is downloading...<br/>';
    /*$url = $_GET['url'];
    $referer = $_GET['referer'];
    $name = $_GET['name'];*/
    $url = "http://stream.get-tune.net/file/91259796/101538464/3652118538/ee58ddeb905ffa12/Palwan_Halmyradow_-_Sensiz_(get-tune.net).mp3";
    $referer = "http://get-tune.net/?a=music&q=palwan+halmyradow";
    $name = "Palwan Halmyradow - Sensiz";
    download($url, $referer, $name);
?>

但是当我从命令行调用下面的命令时，它可以工作:

php /var/www/idym/download.php

有什么问题吗?