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Mail Archives: djgpp/1998/08/18/15:30:34

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: Tue, 18 Aug 1998 19:26:20 GMT
Organization: Guest of France-Teaser
Lines: 41
Message-ID: <35d9d505.4345933@news.teaser.fr>
References: <Pine DOT SUN DOT 3 DOT 91 DOT 980818160339 DOT 12510c-100000 AT is>
NNTP-Posting-Host: ppp2816-ft.teaser.fr
NNTP-Posting-Date: 18 Aug 1998 19:17:47 GMT
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Eli Zaretskii <eliz AT is DOT elta DOT co DOT il> wrote:

>
>On Sun, 16 Aug 1998, JP wrote:
>
>> I've allocated a large array, locked it and set a descriptor to this
>> array. I would like to know the physical address of this array. Can it
>> be determined from the descriptor ?
>
>In general, you can't.  You can only find the logical address, not the 
>physical one.
>
>Please explain why do you need the physical address, then it would be 
>possible to advise about any available solutions.
> 

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. 

Determining the physical address shouldn't be a problem since 
there are solutions to explore the entire physical memory, but I can
find any solution to create a continuous buffer.


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.

I've tried everything I could think of. I've even tried to allocate
and lock an XMS buffer in my autoexec.bat (before Windows 95 loads),
but Windows 95 refuses to start then.

Thanks very much for your answer,
  JP


Jeepy (Jean-Pierre Delprat)
jpdelprat AT teaser DOT fr
www.teaser.fr/~jpdelprat (JPTUI home page)

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