Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!pasteur!ucbvax!CORY.BERKELEY.EDU!dillon
From: dillon@CORY.BERKELEY.EDU (Matt Dillon)
Newsgroups: comp.sys.amiga
Subject: Re: LVOs and SetFunction
Message-ID: <8803060000.AA29981@cory.Berkeley.EDU>
Date: 6 Mar 88 00:00:47 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 23


>First off, where do the LVOs come from? Is there some file (I hope) with them
>defined?  Where does one get this file? 

	LVOs are defined IN the link library...  They are actual symbols
used as offsets.  I suppose you can recover them by decoding the link
library.  Otherwise, if you don't have access to a list you need to
write a program that simply prints their values out.

>Second.  I want to start do some mucking with SetFunction.  I understand the
>principals of how to use it, but I'm not a real assembly-jock.  Does anyone
>have a nice example(entire program) that just does one simple stupid SetFunction.
>?
>If it is mostly in C, I'd be even happier.  
>Thanks.
>

	SetFunction is extremely easy in itself.  However, you must 
conform with the same calling conventions as the original functions,
including preserving the proper registers and getting arguments from
the proper registers.  Thus, SetFunction'd code is usually written in
assembly.  So it depends on the function you are replacing/intercepting.

				-Matt