function nextRaw()
    {
        if ($this->type == self::SOURCE_FILE) {
            $record = stream_get_line($this->source, File_MARC::MAX_RECORD_LENGTH, File_MARC::END_OF_RECORD);

            // Remove illegal stuff that sometimes occurs between records
            $record = preg_replace('/^[\\x0a\\x0d\\x00]+/', "", $record);

        } elseif ($this->type == self::SOURCE_STRING) {
            $record = array_shift($this->source);
        }

        // Exit if we are at the end of the file
        if (!$record) {
            return false;
        }

        // Append the end of record we lost during stream_get_line() or explode()
        $record .= File_MARC::END_OF_RECORD;
        return $record;
    }