Date: Tue, 17 Apr 2001 23:15:40 +0300
From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
Sender: halo1 AT zahav DOT net DOT il
To: "M. Adam Davis" <adavis AT group10 DOT net>
Message-Id: <9743-Tue17Apr2001231540+0300-eliz@is.elta.co.il>
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CC: djgpp AT delorie DOT com
In-reply-to: <3y_C6.7$Gz.1200@nntp0.chicago.il.ameritech.net>
	(adavis AT group10 DOT net)
Subject: Re: 16-bit small dos apps w/o dpmi?
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> From: "M. Adam Davis" <adavis AT group10 DOT net>
> Newsgroups: comp.os.msdos.djgpp
> NNTP-Posting-Date: Tue, 17 Apr 2001 11:53:19 CDT
> 
> Ideally I could make a plain vanilla 16-bit dos application that would run
> on any dos system down to a 386 without any memory managers whatsoever.

You could rewrite your program in assembly and build it with djasm,
which can create 16-bit real-mode programs.

> At minimum how do I go about eliminating the need for the seperate dpmi
> (either by changing the compile options, or embedding the dpmi into my exe).

This is possible with CWSDPMI, see the docs which comes with
csdpmi5b.zip.

> Secondly, even hello world creates an exe which is nearly 200K in size after
> removing debugging information.

Perhaps a C++ program; a minimal C program should be about 31KB, see
section 8.14 of the DJGPP FAQ for details.

> While I realize that the compiler won't
> create the 20 byte com program one could make to do the same thing, I wonder
> what is making my program so large?

The FAQ explains that.

> Are there size optimizations in GCC that I'm unaware of?

Yes.