Function 4405h (68-5)    IOCTL: Write to Block Device

Write a control string to a block device.

On entry:      AH         44h
AL         05h
BL         Drive number (0=default, 1=A, etc.)
CX         Number of bytes to write
DS:DX      Data or buffer

Returns:       AX         Number of bytes written
Error code   If CF is set

Error codes:   1          Device doesn't support control strings
5          Drive is invalid

                                                                          

This subfunction writes CX bytes of data to the block device's control
channel from either DS:DX or from memory pointed to by DS:DX.  How
data is written is defined by the device driver.  Data can be written
only if the device can process control strings.

See also: 44h
See also: 4404h

4405h (68-5) IOCTL: Write to Block Device