NAME
        PRD_WRITEPREFS - write the current driver prefs from a buffer (V44)

   FUNCTION
        This is a non standard write command that writes the driver
        preferences.

   IO REQUEST
        io_Message      mn_ReplyPort set if quick I/O is not possible
        io_Command      PRD_WRITEPREFS
        io_Flags        IOB_QUICK set if quick I/O is possible
        io_Length       the length of the buffer
        io_Data         a buffer
        io_Actual       the number of bytes copied to the driver prefs.

        The printer driver checks the buffer before copying it to its
        preferences. So you don't have to worry about changing the printer
        driver between prd_readprefs and prd_writeprefs.