Message-ID:	<3E51709E.DE111E40@worldnet.att.net>
From:	Paul Cousoulis <paulcsouls AT worldnet DOT att DOT net>
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Newsgroups:	comp.os.msdos.djgpp
Subject:	Passing pointers to dpmi_int
Lines:	16
Date:	Mon, 17 Feb 2003 23:34:53 GMT
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

I'm trying to implement the Virtual DMA Service. In order to lock DMA
memory I need to pass the address of a structure to int 4b in es:di. The
physical address should be returned in dds_local, but I keep getting
zero even though the function seems to otherwise return successfully.
The code I'm using is:
>
>		dr.x.dx = 0;
>		dr.x.ax = 0x8103;
>		temp = (int)(&dds_local);
>		dr.x.es = (unsigned short)(temp>>16);
>		dr.x.di = (unsigned short)(temp & 0xffff);
>		if(__dpmi_int(0x4b,&dr)) printf("error\n");
>
Thanks
Paul

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