vgroup_id	IN:	Vgroup identifier returned by Vattach
	tag_array	OUT:	Array of tags
	ref_array	OUT:	Array of reference numbers
	num_of_pairs	IN:	Number of tag/reference number pairs

	Purpose	Retrieves the tag/reference number pairs of the HDF objects belonging to a vgroup.
	Return value	Returns the number of tag/reference number pairs obtained from a vgroup if successful and FAIL (or -1) otherwise.
	Description	Vgettagrefs retrieves at most num_of_pairs number of tag/reference number pairs belonging to the vgroup, vgroup_id, and stores them in the buffers tag_array and ref_array.
		The input parameter num_of_pairs specifies the maximum number of tag/reference number pairs to be returned. The size of the arrays, tag_array and ref_array, must be at least num_of_pairs.

	FORTRAN	integer function vfgttrs(vgroup_id, tag_array, ref_array, num_of_pairs)
		integer vgroup_id, num_of_pairs
		integer tag_array(*), ref_array(*)