Int D4 Fn 16  - Pc-mos/386 V5.01 - Set/clear Irq Reservation               [O]

   AH = 16h
   AL = function (00h clear, 01h set reservation)
   CX = IRQ number

Return: AX = status
       (0000h successful, 0001h currently reserved by another task)

See Also: AH=07h,INT 14/AH=11h"PC-MOS"