INT 17 - Alloy NTNX, MW386 - GET USER NUMBER AND CURRENT PRINTER                
	AH = 91h
	AL = mode
	    00h NTNX compatibility
		Return: CX = user number (00h = host)
			DX = currently selected printer number (00h-08h)
	    01h MW386
		Return: CX = user number
			DX = physical dev number of currently selected printer
	    02h MW386 v2+
		BX = logical device number
		    00h-03h = LPT1-LPT4
		    04h-07h = COM1-COM4
		Return: CX = user number
			DX = physical device number
Return: AL = status (see #00642)
SeeAlso: AH=8Ch