From:	Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Stubs - definition
Date:	10 Dec 1999 10:30:51 -0800
Organization:	InterWorld Communications
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"sl" <junk AT bbs DOT darktech DOT org> writes:

> Hi,
> 
> 	I was wondering if anyone could explain to me what a file stub is ..
> I've been seeing this word used in the context of DJGPP and other problems
> quite frequently..

The GNU toolchain doesn't produce DOS EXE's by itself.  DJGPP uses the
Unix-born COFF file format.  Of course, DOS doesn't know how to
execute these.  So in order to create an EXE, DJGPP prepends a small
(2K) chunk of code (the stub) to the front.  This contains an EXE
header, and knows how to start DPMI, switch to protected mode, load a
COFF image, etc.  DOS therefore sees an EXE file, which it does know
how to handle, and we go merrily on our way.

-- 

Nate Eldredge
neldredge AT hmc DOT edu

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