From:	Mike McLean <libolt AT primenet DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Questions about 32-bit
Date:	5 Feb 1998 22:04:02 -0700
Organization:	Primenet Services for the Internet
Lines:	33
Message-ID:	<34DA9ABE.4665841@primenet.com>
References:	<6be2pa$m0i$1 AT herald DOT Mines DOT EDU>
MIME-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Jean-Luc Romano wrote:
> 
> Hello again, all,
> 
>    Say, I have a few questions about DJGPP in general.  From what
> I've heard DJGPP is a 32 bit compiler for MS-DOS.  How can that be,
> if MS-DOS is a 16 bit operating system?

DJGPP runs in 32 bit protected mode by use of a DPMI server such as
Win95, Linux Dosemu, and CWSDPMI for dos.  The DPMI server switches the
CPU into protected mode as far as I understand.  It handles all normal
dos calls the program makes.  It also allows your program to use virtual
memory on the hard drive when your RAM fills up.

>    Also, I've seen the use of small, medium, large, and huge memory
> models as well as the mention of near and far pointers in game
> tutorials for Borland and MicroSoft C/C++ compilers.  However, I've
> never seen any mention of them in any DJGPP/Allegro tutorial.
>    Why is that?
> Does this have anything to do with the fact that DJGPP is a 32-bit
> compiler?

Yes it does.  DJGPP is 32 bit and uses the flat memory model.  In other
words, it uses all available memory.  It doesn't require near and far
pointers.  You just allocate the memory.
 
>    Thanks.
> 
>    Jean-Luc Romano

I hope I am of help.

Mike.

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