From: sar AT maties DOT sun DOT ac DOT za
Newsgroups: comp.os.msdos.djgpp
Subject: Re: NASM - How to access vid ram inside DJ
Date: Mon, 16 Jun 1997 15:56:16 -0700
Organization: University of Potchefstroom
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Message-ID: <33A5C490.101F@maties.sun.ac.za>
References: <33A083D9 DOT 11AC AT pukopn1 DOT puk DOT ac DOT za> <01bc79c6$2ee9efe0$fd8033cf AT pentium>
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Gil Myers wrote:
> 
> acebear AT pukopn1 DOT puk DOT ac DOT za wrote in article
> <33A083D9 DOT 11AC AT pukopn1 DOT puk DOT ac DOT za>...
> > How would you write a NASM generated COFF .o that will make it possible
> > to directly access VGA memory (320x200) under DJGPP directly from an
> > external, NASM coded asm prog without the usual slew of segment
> > violation errors?

>> Workaround one is to  turn off protection.  This is described in the FAQ,
> and the
> actual functions to do so are in the file SYS/NEARPTR.H.  This is very
> dangerous.

Why is it dangerous? I checked the FAQ & docs you refer to, they also
discourage it, but it looks like THE fastest method. Since memory
protection is there to prevent different programs in the same physical
memory of stepping on each other, and DJGPP always runs as the only
program in its memory space, what is the problem?

Sorry, I am a newbie and I am just interested.

Fanx for the reply to my post!

Rylan