public function offset($offset = false, $seek = SEEK_SET)
    {
        if ($offset === false) {
            if (is_resource($this->handle)) {
                return ftell($this->handle);
            }
        } elseif ($this->open() === true) {
            return fseek($this->handle, $offset, $seek) === 0;
        }

        return false;
    }