vdata_id	IN:	Vdata access identifier returned by VSattach
	n_records	OUT:	Number of records in the vdata

	Purpose	Retrieves the number of records in a vdata.
	Return value	Returns SUCCEED (or 0) if successful and FAIL (or -1) otherwise.
	Description	VSQuerycount retrieves the number of records in the vdata identified by vdata_id in the parameter n_records.

	FORTRAN	integer function vsqfnelt(vdata_id, n_records)
		integer vdata_id, n_records