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Visual C++

prtsc3.asm：源码内容

							;*
;*	COW : Character Oriented Windows
;*
;*	prtsc.asm : ^PrtSc stuff.
	include kernel.inc
	include inscr.inc		;* for inst
;----------------------------------------------------------------------------
externFP	<HandlerInt05Dead>
;----------------------------------------------------------------------------
sBegin	DATA
    assumes DS,DATA
externB	fGrabInt05
externW	OFF_pfnHdlrInt05
externW	SEG_pfnHdlrInt05
sEnd	DATA
;----------------------------------------------------------------------------
sBegin	INIT
    assumes CS,INIT
    assumes SS,DATA
    assumes DS,DATA
;----------------------------------------------------------------------------
;
; Reroute interrupt 05 (^PrtSc) if necessary.
;
;   entry:  ds:bx -> inst structure.
;
;   preserve BX!
segROM	equ	0F000h
    assumes CS,INIT
    assumes DS,DGROUP
    assumes SS,DGROUP
    assumes ES,NOTHING
cProc	ReroutePrtSc,<FAR,PUBLIC,ATOMIC>
cBegin	ReroutePrtSc
	cmp	fGrabInt05,0			; If latch is dropped, int05
	jne	dontgrab			;   is already rerouted okay.
	mov	ax,SEG_pfnHdlrInt05		; AX:DX -> the original
	mov	dx,OFF_pfnHdlrInt05		;   int05 vector.
	cmp	ax,segROM			; If the old int05 didn't
	jne	@F				;   point to ROM, use it.
	test	[bx].finstInst,finstGraphics	; If we're not going to gfx
	jz	@F				;   mode, use old int05.
	mov	ax,SEG kernelBase		; Gfx mode w/ ROM int05:
	mov	dx,kernelOffset HandlerInt05Dead ;   reroute to dead routine.
@@:
	push	ds
	mov	ds,ax				; DS:DX -> new int05 vector.
    assumes ds,NOTHING
	mov	ax,2505h
	int	21h
	pop	ds
    assumes ds,DGROUP
dontgrab:
cEnd	ReroutePrtSc
sEnd	INIT
;----------------------------------------------------------------------------
	END

						