dim_id	IN:	Dimension identifier returned by SDgetdimid
	comp_mode	IN:	Compatibility mode to be set

	Purpose	Determines whether a dimension will have the old and new representations or the new representation only.
	Return value	Returns SUCCEED (or 0) if successful and FAIL (or -1) otherwise.
	Description	SDsetdimval_comp sets the compatibility mode specified by the comp_mode parameter for the dimension identified by the dim_id parameter. The two possible compatibility modes are: "backward-compatible" mode, which implies that the old and new dimension representations are written to the file, and "backward-incompatible" mode, which implies that only the new dimension representation is written to the file.
		Unlimited dimensions are always backward-compatible, therefore SDsetdimval_comp takes no action on unlimited dimensions.
		As of HDF version 4.1r1, the default mode is backward-incompatible. Subsequent calls to SDsetdimval_comp will override the settings established in previous calls to the routine.
		The comp_mode parameter can be set to SD_DIMVAL_BW_COMP (or 1), which specifies backward-compatible mode, or SD_DIMVAL_BW_INCOMP (or 0), which specifies backward-incompatible mode.

	FORTRAN	integer function sfsdmvc(dim_id, comp_mode)
		integer dim_id, comp_mode