public function readInt16()
    {

        // Change the integer type we are looking up
        switch ($this->number_type) {
            case self::NUMBER_TYPE_BIGENDIAN:
                $type = 'nint';
                break;

            case self::NUMBER_TYPE_LITTLEENDIAN:
                $type = 'vint';
                break;

            default:
                $type = 'Sint';
        }

        $int = unpack($type, $this->read(2));

        return $int['int'];
    }