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Mail Archives: djgpp/1995/05/14/01:15:23

Date: Sat, 13 May 95 23:59:29 -0400
From: Wonkoo Kim <wkim+@pitt.edu>
To: rbabcock AT cfa DOT harvard DOT edu, djgpp users <djgpp AT sun DOT soe DOT clarkson DOT edu>
Reply-To: Wonkoo Kim <wkim+@pitt.edu>
Subject: Re: Dumb Newbie Question Re:Low Memory Accesss

> Date: Sat, 13 May 95 22:34:42 -0400
> From: peprbv AT cfa0 DOT harvard DOT edu
> Reply-To: rbabcock AT cfa DOT harvard DOT edu
> Subject: Re: Dumb Newbie Question Re:Low Memory Accesss
> 
> > Don't worry about pointer types like 'near' or 'far' or 'huge' etc. 
> > when you use djgpp.  Memory space is 32-bit linear with djgpp, and
> > you can write programs without headache of memory segment.
> 
> But, under dpmi, the linear memory space doesn't include the first MB of
> memory.  So if you want access to video memory, you have to use library
> function calls, sys/farptr.h, assembly language or similar.  This makes your
> life a little more difficult if you are porting from DOS to djgpp, but it's
> not bad if all your screen output gets routed through a small number of
> routines.

Yes, right.  Thanks for the additional comment.

The above answer was for a "newbie" who would not touch the first MB RAM 
(like video RAM) by himself.  Otherwise, he/she may not be a newbie. :-)

//--------------------------------------------------------------------
// Wonkoo Kim
// wkim+@pitt.edu

- Raw text -


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