def find(self, vName):
        """Get the reference number of a vdata given its name.
        The vdata can then be opened (attached) by passing this
        reference number to the attach() method.

        Args::

          vName    Name of the vdata for which the reference number
                   is needed. vdatas names are not guaranteed to be
                   unique. When more than one vdata bear the same name,
                   find() will return the refnum of the first one founmd.

        Returns::

          vdata reference number. 0 is returned if the vdata does not exist.

        C library equivalent : VSfind
                                               """

        refNum = _C.VSfind(self._hdf_inst._id, vName)
        _checkErr("find", refNum, "cannot find vdata %s" % vName)
        return refNum