def info(self):
        """Retrieve info about the attribute.

        Args::

          no argument

        Returns::

          4-element tuple with the following components:
            -attribute name
            -attribute data type (one of HC.xxx constants)
            -attribute order (number of values)
            -attribute size in bytes

        C library equivalent : Vattrinfo
                                                           """

        # Make sure the attribute exists.
        if self._index is None:
            raise HDF4Error("non existent attribute")

        status, name, type, order, size = \
                _C.Vattrinfo(self._v_inst._id, self._index)
        _checkErr('info', status, "execution error")
        return name, type, order, size