Category: <b>DOS kernel</b>
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<pre><b>INT 21 - DOS 2+ - IOCTL - WRITE TO BLOCK DEVICE CONTROL CHANNEL</b>

	AX = 4405h
	BL = drive number (00h = default, 01h = A:, etc)
	CX = number of bytes to write
	DS:DX -&gt; data to write
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:	format of data is driver-specific
	this function was not supported by Digital Research's DOS Plus
SeeAlso: AX=4403h"DOS",AX=4404h"DOS",INT 2F/AX=122Bh
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