Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!dartvax!eleazar.dartmouth.edu!earleh
From: earleh@eleazar.dartmouth.edu (Earle R. Horton)
Newsgroups: comp.sys.mac.programmer
Subject: Re: DDPWrite Problem found
Message-ID: <14249@dartvax.Dartmouth.EDU>
Date: 6 Jul 89 17:16:36 GMT
References: <5920@hubcap.clemson.edu> <7869@hoptoad.uucp>
Sender: news@dartvax.Dartmouth.EDU
Reply-To: earleh@eleazar.dartmouth.edu (Earle R. Horton)
Organization: Thayer School of Engineering
Lines: 28

In article <7869@hoptoad.uucp> tim@hoptoad.UUCP (Tim Maroney) writes:
>In article <5920@hubcap.clemson.edu> mikeoro@hubcap.clemson.edu (Michael
>K O'Rourke) writes:
>>Thanks to those who responded to my earlier problem with a DDPWrite call
>>causing an error code of -95. It turned out I was trying to access data in 
>>a nil pointer earlier in the program and this ended up writing to some 
>>nasty area of memory, which caused the DDPWrite error.  
>
>Gosh, I wonder why we nasty ol' developers keep begging Apple for a
>memory protected OS.  It must be that we're just jerks -- after all, we
>disagree with stated Apple policy and plans, and only a real asshole
>would do that.  There couldn't possibly be a good reason we consider
>memory protection important, could there?

     After having spent the better part of a day chasing down a bug in
my program which caused it to repeatedly fill up the Finder's code
space with garbage, I couldn't agree with Tim more.

     There is, however, a fairly simple test for Handle nihilism.  Run
your code on a 68000 machine, stuff something odd in the longword at
location zero, and wait for System Error 2.  If your code runs on more
advanced processors only, put something there which will generate a
Bus Error.  Technote 7 suggests the value 'NIL!' will work for both.

Earle R. Horton

"People forget how fast you did a job, but they remember how well you
did it."  Salada Tag Lines