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From: Charles Sandmann <sandmann AT clio DOT rice DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: V2 Math Libraries and Emulation
Date: Sun, 26 Nov 1995 21:27:27 CST
Organization: Rice University, Houston, Texas
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> With all these math libraries (LIBEMU, LIBM, LIBWEMU) and emulators 
> (EMU387.DXE, WMEMU387.DXE) which one(s) are you supposed to use and do 
> you use them.  By default I know that LIBC includes loading of 
> EMU387.DXE, so why the libraries??

If you want a standalone V2 image which can be run on a system without
packaging EMU387.DXE, you can link with -lemu and the code which is in
EMU387.DXE will be imbedded in your image.

WMEMU is an alternate emulator which more closely mimics a real coprocessor,
but is larger in size and GPL.  This means you must distribute the source if
you distribute WMEMU387.DXE, and you cannot link with -l wmemu without all
the GPL restrictions.  Yet another non-documented tidbit; you must use 
WMEMU if you want to debug FPU applications on a non-FPU system.  This is
because WMEMU knows a little bit about "far" while EMU387 doesn't.

So, each image has it's pros and cons, so the developer gets to decide
which he wants to use and when.  BTW, the DXE setup was first required 
so we could work around using the GPLed WMEMU with non-GPLed commercial images.

> Any help would be greatly appreciated.  If this is a FAQ, then forgive 
> my ingorance, but I did quickly (underline quickly) look through the FAQ.

No, I doubt we have documented this at all.  Better archive this for the V2
DOCS...