Message-ID: <3287ECA7.4EF7@gbrmpa.gov.au>
Date: Tue, 12 Nov 1996 11:19:03 +0800
From: Leath Muller <leathm AT gbrmpa DOT gov DOT au>
Reply-To: leathm AT gbrmpa DOT gov DOT au
Organization: Great Barrier Reef Marine Park Authority
MIME-Version: 1.0
To: Ely Wilson <fletch AT netdoor DOT com>
CC: djgpp AT delorie DOT com
Subject: Re: DJGPP pointers
References: <Pine DOT GSO DOT 3 DOT 94 DOT 961111132053 DOT 20921A-100000 AT netdoor DOT com>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

> So, is a pointer a selector AND an offset, or just a 32bit offset into a
> 4G selector...in which case, how the heck am I supposed to make use of
> pointers which use a 16bit base and 16bit offset...i suppose I could calc
> the effective addx, huh?  Anyhow, which is it?  Sel AND offset or jyust an
> offset?  Thank you for replying, but I'm still not totally clear on this.

Don't confuse yourself with segments, offsets, etc. Your in protected
mode
now - no 16 bit segments if you don't want them. No 16 bit offsets at
all,
all offsets are 32 bit (I think... :) You shouldn't have to really worry
about segments or selectors at all if you don't want to...

If you clarify _what_ you want to know this for, people may be able to
help you a bit better. If your video api is accessing real mode memory
and/or using VBE 1.2, you would have to access the video memory in
a different way than if your coding for the VBE 2.0 standard with a
linear
frame buffer. If your coding for a LFB, you can just have a single int
(or char * or whatever) pointer to a memory location. 1 32 bit value.
End of story... :)

Leathal.