Category: <b>MS Windows</b>
<br>Flags: callout or callback (usually hooked rather than called)<p>
<pre><b>INT 2F - MS Windows 3.1 - "BLOCKDEV" VIRTUAL HARD DISK DEVICE API</b>

	AX = 1607h
	BX = 0010h (VxD identifier of "BLOCKDEV")
	CX = function
	    0001h starting FastDisk compatibility tests
	    0002h ending FastDisk compatibility tests
	    0003h check if FastDisk installation allowed
		Return: CX = 0000h if allowed
Note:	this interface is called by the Windows FastDisk driver (such as
	  WDCTRL) when it thinks that the INT 13h handler immediately below
	  IO.SYS's INT 13h code is not in ROM; it should be supported by any
	  program which hooks itself underneath IO.SYS's INT 13h code with
	  INT 2F/AH=13h
SeeAlso: AX=1607h/BX=0014h,INT 2F/AH=13h
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