INT 2F U - DOS 5.0+ SETUP                                                       
	AH = 49h
	AL = function
	    00h update format completion gauge
		BX = percentage complete, 0000h when done, FFFFh if aborted
		Return: AX = status
			    0000h continue formatting
			    else  installation program wants FORMAT to abort
	    10h get pointer to resident data
		AX = FFFFh if supported
		    ES:BX -> internal structure
	???
Return: ???