From: DJ Delorie <dj AT delorie DOT com>
Newsgroups: comp.os.msdos.djgpp,rec.games.programmer
Subject: Re: New to djgpp... help:)
Followup-To: comp.os.msdos.djgpp
Date: 27 Dec 1997 20:57:07 -0500
Organization: DJ Delorie/DJGPP Support
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References: <34A571B3 DOT E839946A AT stayfree DOT co DOT uk>
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Nat Saiger <lunchbox AT stayfree DOT co DOT uk> writes:
> Are programs compiled under DJGPP automatically in protected mode, or do
> you have to put your program INTO protected mode?

It's automatic.

> Do you have to be in a DOS shell in windows to use protected mode?

No, but you need a DPMI host.  DJGPP has one if you need it, called
cwsdpmi (in Simtel's v2misc directory)

> If all DOS memory is protected, how do you access the video memory?

DJGPP creates a selector that references DOS memory, plus provides
some functions for accessing it.  The FAQ includes other methods.

> Do I have to learn AT&T syntax for assembly, or is there a converter
> from 80x86 to AT&T?

You can use NASM to write assembler for DJGPP.  It supports Intel's
syntax.  For inline assembler, you need to learn AT&T *and* the special
syntax gcc uses.