From: jpdelprat AT teaser DOT fr (JP)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: How to determine the physical address from a DPMI descriptor
Date: Sun, 23 Aug 1998 18:10:52 GMT
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Eli Zaretskii <eliz AT is DOT elta DOT co DOT il> wrote:

>
>On Tue, 18 Aug 1998, JP wrote:
>
>> My need is to create and lock a 2Mo continuous buffer (under Windows
>> 95), and determine its physical address to give it to a video capture card.
>
>I think section 18.7 of the FAQ should get you started.
>
>> With DPMI functions (under Windows 95), I allocate my buffer then 
>> lock it, but despite the call to dpmi_lock_linear_region, the buffer
>> is still mixed and partially swapped out.
>
>Did you remember to make your segment to have a size that's a multiple of 
>4KB?

Thanks for the advice. I hadn't noticed this point. Fortunately, my
buffer is exactly 2M. So it should be ok. 

I have found another solution : I allocate and lock an xms buffer
before Windows starts. This buffer is continuous and cannot be used by
Windows. The drawback is that my system now has less memory. I would
prefer to allocate my buffer when I run my program, but I could find
any way.

Thanks very much, 
  JP
Jeepy (Jean-Pierre Delprat)
jpdelprat AT teaser DOT fr
www.teaser.fr/~jpdelprat (JPTUI home page)