Date: Wed, 31 Dec 1997 09:49:52 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Nat Saiger <lunchbox AT stayfree DOT co DOT uk>
cc: djgpp AT delorie DOT com
Subject: Re: What is __djgpp_conventional_base ??
In-Reply-To: <34A97AB5.14FD6E93@stayfree.co.uk>
Message-ID: <Pine.SUN.3.91.971231094932.3217J-100000@is>
MIME-Version: 1.0
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On Tue, 30 Dec 1997, Nat Saiger wrote:

>     and it didn't work, so I downloaded a tutorial on video memory under
> djgpp, and it used the line
> 
>         unsigned char *videoptr = (unsigned char *)0xA0000 +
> __djgpp_conventional_base;
> 
>     What is __djgpp_conventional_base? There is no mention of it in
> Rhide's syntax help and the document didn't explain it.

This is explained in the DJGPP FAQ list, section 18.5, and in the
DJGPP library reference under __djgpp_nearptr_enable.  (The FAQ is
available as v2/faq210b.zip from the same place you get DJGPP.)

>     Also, which is the FASTEST way to access the video memory, enabling
> near pointers or emulating far pointers?? (or is there a better way)

On most systems, near pointers and far pointers yield the same speed.
The FAQ lists several alternatives of accessing conventional memory in
section 18.4.