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From: mnkonar@gorby.SRC.Honeywell.COM (Murat N. Konar)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Tail Patching and ROM replacement
Message-ID: <41304@srcsip.UUCP>
Date: 2 Dec 89 00:12:20 GMT
References: <17539@dartvax.Dartmouth.EDU>
Sender: news@src.honeywell.COM
Reply-To: mnkonar@gorby.UUCP (Murat N. Konar)
Distribution: na
Organization: Honeywell Systems & Research Center, Camden, MN
Lines: 31


Tail patching is for quiche-eaters who don't want to learn how 
the stack works and how to fix things in assembly.  Face it,
programming the Mac is a challange.  You have to go beyond
the compiler and really understand what's going on when you
are patching traps.  And get this: sometimes you can still
screw things up EVEN USING A HEAD PATCH! For example, there are 
times when all registers must be preserved (LoadResource 
comes to mind). 

If you want to learn more about what the compiler does
and how the stack works, go buy Scott Knaster's "How
to Write Macintosh Software."  It even has a discussion
of why tail patching is evil.

I'm sure there are rare cases when only a tail patch will 
work (can't think of any though), but I can't belive that all
the whiners out there can't do what they want to some other
way.  Just be smarter about it.

Sheesh.

P.S.  I don't think that ROM's should be made replacable so that 
someone can use a tail patch to make flushing noises when the 
toilet (trash) is flushed (emptied).


____________________________________________________________________
Have a day. :^|
Murat N. Konar        Honeywell Systems & Research Center, Camden, MN
mnkonar@SRC.honeywell.com (internet) {umn-cs,ems,bthpyd}!srcsip!mnkonar(UUCP)