INT 2F - DESQview v2.26+ External Device InterfaceA series of calls made by the DESQview multitasker on various "interesting" events, which may be intercepted by programs which wish to keep track of the current system state.	 See also Callout. - DRIVER CUSTOM SUBFUNCTION
	AX = DE01h
	BX = driver ID
	other registers as needed by driver
Notes:	XDIsee External Device Interface drivers should pass this call through to previous handler if ID
	  does not match
	DESQview never calls this function