Path: utzoo!attcan!uunet!samsung!usc!apple!apple.com!chewy
From: chewy@apple.com (Paul Snively)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Tail patches
Message-ID: <5249@internal.Apple.COM>
Date: 17 Nov 89 17:06:37 GMT
Sender: usenet@Apple.COM
Organization: Apple Computer, Inc.
Lines: 50
References:<1459@sequent.cs.qmc.ac.uk> <36250@apple.Apple.COM> <5056@internal.Apple.COM> <1989Nov7.212837.5146@oracle.com> <26596@santra.UUCP> <5148@internal.Apple.COM> <26693@santra.UUCP> <5212@internal.Apple.COM> <1989Nov16.043300.8959@eng.umd.edu>

In article <1989Nov16.043300.8959@eng.umd.edu> russotto@eng.umd.edu 
(Matthew T. Russotto) writes:
> In article <5212@internal.Apple.COM> chewy@apple.com (Paul Snively) 
writes:
> >
> >And I'd be interested in any examples of "something that we have 
decided to
> > break," let alone something that we have decided to break and then not 
fix.
> Resource Header Application Bytes.  Resource References.  The 'abort 
event'.
> 'Launch'  (well, you haven't broken it yet, but you keep promising to do 
so).
> 'Chain'.  JMP 10(ROMBASE) to restart....
> (and, of course, tail patching-- it did used to work)

* Resource Header Application Bytes
   What on earth are those?

* Resource References
   Macintosh Developers were asked whether this would affect them adversely;
   to the best of my knowledge, no one ever used them, so they were disposed
   of (actually, the trap numbers were assigned to new routines).  How many 
   Macintosh applications broke as a result?

* The "Abort Event."
   Again, what on earth is this?  It's nowhere in Inside Macintosh or the Tech 
   Notes.

* Launch and Chain
   The semantics of Launch will indeed change, but for the better (right now 
   there's no prima facie way to know whether the _Launch trap will return or 
   not; it depends upon whether you're running under MultiFinder or not).  In 
   this case, I'd say we broke it when we released MultiFinder, and now we're 
   fixing it.

* JMP 10(ROMBASE) to restart
   That was never supported; it just happened to work.  Now, of course, we 
   have a Shutdown Manager that actually does the right things.

* Tail Patching (it used to work)
   Wrong.  There was NEVER a time in Macintosh history when tail patching did 
   not break the software.

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Just because I work for Apple Computer, Inc. doesn't mean that they 
believe what I believe or vice-versa.
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