public function ls($remote_dir)
    {
        $dir = "ssh2.sftp://".$this->sftp.$remote_dir;
        $handle = opendir($dir);
        $files = Array();
        while (false !== ($file = readdir($handle))) {
            if (substr($file, 0, 1) != '.'){
                $files[] = $file;
            }
        }

        closedir($handle);

        return $files;

    }