INT 15 - DESQview v2.50+ - "VIDEONOTIFY" - HAS DIRECT WINDOW BEEN ACTIVE?
        AX = DE2Fh
Return: BX = status
            0001h keyboard focus has been given to a direct window since the
                last call
            0000h if not
Notes:  DESQview 2.50-2.52 are distributed as part of DESQview/X v1.0x.
        Quarterdeck states that this call will not be available under future
          versions of DESQview Classic