Date: Sun, 19 Oct 1997 16:54:04 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Georg Kolling <Georg DOT Kolling AT t-online DOT de>
cc: djgpp AT delorie DOT com
Subject: Re: Physical address from array ? Not a clue!
In-Reply-To: <m0xLvQb-0003LdC@fwd03.btx.dtag.de>
Message-ID: <Pine.SUN.3.91.971019165335.27221I-100000@is>
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On Thu, 16 Oct 1997, Georg Kolling wrote:

> Eli Zaretskii schrieb:
> > I imagine that if you allocate a DOS buffer, you can use its address as 
> > the physical address, since DOS memory is usually mapped 1-to-1.
> 
> Usually it is, but not in a multitasking OS!

If you are thinking about Windows, then you still can treat the first
1MB as mapped 1:1.  Windows traps all DMA requests and transparently
changes the addresses there so DOS programs that were written assuming
they get physical addresses, still work.