Date: Thu, 22 Apr 1999 12:12:44 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: yjtseng <yjtseng AT micron DOT com>
cc: djgpp AT delorie DOT com, salvador AT inti DOT gov DOT ar, nate AT cartsys DOT com
Subject: Re: What if?
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On Wed, 21 Apr 1999, yjtseng wrote:

> Question: Can I now use __dpmi_physical_address_mapping( physical_base_addr,
> SIZE) to get a linear_base_addr2  for the allocated memory so that it cam be
> used to  access the same physical memory? Should linear_base_addr2 be the
> same as linear_base_addr1?

I think the mapping of the linear address to the physical one can only
change if the DPMI host or the underlying OS swaps some pages out or
in.  Otherwise, I think the mapping should stay put.

Note that the base address associated with _my_ds() can also change;
see the discussion of the nearptr technique in the FAQ.