ri_id	IN:	Raster image identifier returned by GRcreate or GRselect
	interlace_mode	IN:	Interlace mode

	Purpose	Specifies the interlace mode to be used in the next palette read operation(s).
	Return value	Returns SUCCEED (or 0) if successful and FAIL (or -1) otherwise.
	Description	GRreqlutil requests that the subsequent read operations on the palette attached to the image identified by the parameter ri_id, use the interlace mode interlace_mode.
		The parameter interlace_mode specifies the interlace mode in which the data will be stored in memory when being read. Valid values of the parameter interlace_mode are MFGR_INTERLACE_PIXEL (or 0), MFGR_INTERLACE_LINE (or 1) and MFGR_INTERLACE_COMPONENT (or 2).

	FORTRAN	integer function mgrltil(ri_id, interlace_mode)
		integer ri_id, interlace_mode