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From: sandmann AT clio DOT rice DOT edu (Charles Sandmann)
Message-Id: <10112210608.AA18063@clio.rice.edu>
Subject: Re: RFC - Dynamic loading (partial prototype)
To: djgpp-workers AT delorie DOT com
Date: Fri, 21 Dec 2001 00:08:00 -0600 (CST)
In-Reply-To: <10112200510.AA19496@clio.rice.edu> from "Charles Sandmann" at Dec 19, 2001 11:10:36 PM
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I've got handling of imports working - I was able to look at the
symbol details to tell the difference between absolute and relatives.
So I've got a DXE which uses malloc and printf's to the screen.  It 
can also play with errno (memory) from the dxe.  The extra fixup code
currently adds about 80 bytes to dxeload (which noone would ever
notice).  I created a new global _dxe_fixup pointer where the caller
can set the appropriate offsets for imports.

I didn't mess with multiple export symbols (yet) since I decided 
handling imports and supporting multiple exports easier were 
really two different features (you should be able to handle imports
with a single routine interface like today).

If your "main" program modules are compiled -g then when you step
into the DXE code any references (like malloc or errno) in the 
main code code do show up symbolically.  No line numbers or
internal symbols.

It's just a prototype right now, but it gives an idea of what I
was thinking about and how it might be useful for dll'ing some
chunks of the libc.