PHP 远程下载文件不完整

<code>if(! function_exists('remote_file')) {
    
    function remote_file($url = '', $filename = '') {
        //set_time_limit(0);
        if(! $url) {
            return false;
        }
        if(!file_exists('../static/porn/') && !mkdir('../static/porn/', 0777, true)) {
            return false;
        }
        
        $ext = strrchr($url, ".");
        
        if(! $filename) {
            $filename = time() . $ext;
        }
        
        ob_start();
        readdir($url);
        $content = ob_get_contents();
        ob_end_clean();
        $size = strlen($content);
        $fp2 = @fopen('../static/porn/'.$filename, 'a');
        fwrite($fp2, $content);
        fclose($fp2);
        return config_item('static_site')."porn/{$filename}";
    }
}</code>

<code>if(! function_exists('remote_file')) {
    
    function remote_file($url = '', $filename = '') {
        //set_time_limit(0);
        if(! $url) {
            return false;
        }
        if(!file_exists('../static/porn/') && !mkdir('../static/porn/', 0777, true)) {
            return false;
        }
        
        $ext = strrchr($url, ".");
        
        if(! $filename) {
            $filename = time() . $ext;
        }
        
        ob_start();
        readdir($url);
        $content = ob_get_contents();
        ob_end_clean();
        $size = strlen($content);
        $fp2 = @fopen('../static/porn/'.$filename, 'a');
        fwrite($fp2, $content);
        fclose($fp2);
        return config_item('static_site')."porn/{$filename}";
    }
}</code>