Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!apple!tecot
From: tecot@Apple.COM (Ed Tecot)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Re: Legal Tail Patches
Message-ID: <26341@apple.Apple.COM>
Date: 24 Feb 89 23:16:00 GMT
References: <1285@ccnysci.UUCP> <10050076@accuvax.nwu.edu> <19886@santra.UUCP>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 18

In article <19886@santra.UUCP> jmunkki@kampi.hut.fi.UUCP (Juri Munkki) writes:
>To illustrate:
>Before patching				After patching
>_______________				______________
>Program calls a trap			Program calls a trap
>Trap dispatcher calls routine		Trap dispatcher calls routine
>Come-from patch does something 		Come-from patch does something
>Come-from patch calls ROM		Come-from patch calls new patch.
>					New patch calls ROM...
>
>Apple: Please implement this in the next system release...

The major problem with this is that it will make the trap dispatcher
significantly slower.  Considering that it is the most executed code in
Macintosh, it would probably translate into a significant performance
degradation.  So I ask, is it worth it?

						_emt