INT 21 - DOS 3.1+ network - GET REDIRECTION MODE                                
	AX = 5F00h
	BL = redirection type
	    03h printer
	    04h disk drive
Return: CF set on error
	    AX = error code (see #01680 at AH=59h/BX=0000h)
	CF clear if successful
	    BH = redirection state
		00h off
		01h on
Note:	calls INT 2F/AX=111Eh with AX on top of the stack
SeeAlso: AX=5F01h,INT 2F/AX=111Eh