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Table 2749

Format of XMS driver entry point:
Offset	Size	Description	)
 00h  5 BYTEs	jump to actual handler
		either short jump (EBh XXh) followed by three NOPs or
		  far jump (EAh XXXX:XXXX) to a program which has hooked itself
		  into the XMS driver chain
Note:	to hook into the XMS driver chain, a program should follow the chain of
	  far jumps until it reaches the short jump of the driver at the end
	  of the chain; this short jump is to be replaced with a far jump to
	  the new handler's entry point, which should contain a short jump
	  followed by three NOPs.  The new handler must return to the address
	  pointed at by the short jump which was overwritten.  Using this
	  method, the new handler becomes the first to see every XMS request.

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  Copyright 2000   by Ralf Brown     Updated Jul 2000