NAME
    Write -- send output to parallel port

FUNCTION
    This command causes a stream of characters to be written to the
    parallel output register. The number of characters is specified in
    io_Length, unless -1 is used, in which case output is sent until
    a zero byte occurs in the data. This is independent of, and may be
    used simultaneously with setting the EOFMODE in io_ParFlags and using
    the PTermArray to terminate the read or write.

IO REQUEST
    io_Message      mn_ReplyPort initialized
    io_Device       set by opendevice
    io_Unit         set by opendevice
    io_Command      CMD_WRITE (03)
    io_Flags        If IOF_QUICK is set, driver will attempt Quick IO
    io_Length       number of characters to transmit, or if set
                    to -1 send until zero byte encountered
    io_Data         pointer to block of data to transmit

RESULTS
    io_Error -- If the Write succeded, then io_Error will be null.
         If the Write failed, then io_Error will contain an error code.

SEE ALSO
    parallel.device/pdcmd_setparams