Category: <b>DESQview/TopView and Quarterdeck programs</b>
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<pre><b>INT 2F - DESQview v2.26+ External Device Interface - INSTALLATION CHECK</b>

	AX = DE00h
	BX = 4456h ("DV")
	CX = 5844h ("XD")
	DX = 4931h ("I1")
Return: AL = FFh if installed (even if other registers do not match)
	if BX,CX, and DX were as specified on entry,
	    BX = 4845h ("HE")
	    CX = 5245h ("RE")
	    DX = 4456h ("DV")
Range:	AH=C0h to AH=FFh, selected by scanning AH=DEh-FFh, then AH=C0h-DDh
Note:	the XDI handler should not issue any DOS or BIOS calls, nor should it
	  issue DESQview API calls other than those allowed from hardware ints
SeeAlso: AX=DE02h,INT 15/AX=5400h
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