Category: <b>disk I/O enhancements</b>
<p>
<pre><b>INT 21 - CD-ROM device driver - IOCTL OUTPUT</b>

	AX = 4403h
	BX = file handle referencing character device for CD-ROM driver
	CX = number of bytes to write
	DS:DX -&gt; control block (see <a href=../../it/24/15.html>#01524</a>)
Return: CF clear if successful
	    AX = number of bytes actually written
	CF set on error
	    AX = error code (01h,05h,06h,0Dh) (see <a href=../../it/80/16.html>#01680</a> at AH=59h/BX=0000h)
Notes:	some device drivers support several subunits (that is more than one
	  drive) but it is not possible to distinguish between them with this
	  function; use INT 2F/AX=1510h or INT 2F/AX=0802h instead
	under Windows95, the "mscd$$$$" device cannot be opened so you cannot
	  obtain the handle required by this function: use INT 2F/AX=1510h
	  or INT 2F/AX=0802h instead
SeeAlso: AX=4402h"CD-ROM",INT 2F/AX=0802h,INT 2F/AX=1510h

</pre>