Int 15 Fn 2001 U - DOS 3+ Print.com - Set Critical Region Flag [c] AX = 2001h ES:BX -> byte which is to be incremented while in a DOS call Desc: specify a user flag which PRINT should set to let an interested application know it is in a critical region Note: also supported by PC Network v1.00 RECEIVER.COM See Also: AX=2000h