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Function 4401h          Set Device Data

    Tells DOS how to use the device referenced by the specified
    handle. This function cannot change how DOS uses a file.

        Entry   AX = 4401h
                BX = Device handle
                DX = Device information

        Return  AX changed
                or
                AX = Error code, if CF is set
                     | 01h Invalid function
                     | 05h Access denied
                     | 06h Invalid handle
                     | 0Dh Invalid data

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    The information passed in the DX register is:

                Bit     Description
                0       1 = Console input device
                1       1 = Console output device
                2       1 = Null device
                3       1 = Clock device
                4       1 = Special device
                5       1 = Binary mode, 0 = ASCII mode
                6       0 = EOF returned if device is read
                7       Must be 1 to indicate a device
                8-15    Must be 0