Format of TKERNEL response buffer:
Offset	Size	Description	)
 00h  4 BYTEs	signature "IABH"
 04h	WORD	success indicator
		0001h failed (INT 2F hooked by another program)
		unchanged if successful
 06h	WORD	segment of ???
 08h	WORD	segment of ??? memory block to free if nonzero
 0Ah	WORD	segment of ??? memory block to free if nonzero