INT 15 - DESQview v2.23+ - "DOSUSER" - GET HANDLE OF TASK CURRENTLY USING DOS
AX = DE1Fh
Return: BX = segment of task handle or 0000h if no tasks are using DOS
Note:   this API call may be made from within a hardware interrupt handler

See also: 15DE13

15DE1F - DESQview v2.23+ - "DOSUSER" - GET HANDLE OF TASK CURRENTLY USING DOS