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  Interrupt:   21h     Function:   44h     Subfunction:   03h
 
  Title:       IOCTL: Write Control Data to Character Device Driver
 
  Description:
 
     Transfers control data from an application to a character device
     driver. The length and contents of the data are specific to each
     device driver and do not follow any standard format. This function
     does not necessarily result in any output to the physical device.
 
     Input                              Output
 
     AH = 44h                           If function successful
     AL = 03h                             Carry flag: clear
     BX = Handle                          AX = Bytes transferred
     CX = Number of bytes to write
     DS:DX = segment:offset of data     If function unsuccessful
                                          Carry flag: set
                                          AX = Error code (01h, 05h, 06h,
                                               or 0Dh)
                                          See: ◄Error codes►
                                    -♦-