Re: Font Manager 601 & Teach Bug [Was System 602]

[nathan@cco.caltech.edu (Nathan Mates)]

In article <4gko7a$1d7@cello.gina.calstate.edu>,
LA County Outdoor Science School <lacoss@cello.gina.calstate.edu> wrote:
>nathan@cco.caltech.edu (Nathan Mates) writes:
>> Finder 6.0.1 - Memory trashing bug caused by unrelocated code. Fixed
>> in Rebuilder, published by Softdisk Publishing.

>I'd like to know more about this one.  What does the bug do? How is it 
>produced? What does Rebuilder do to fix it? If Rebuilder is necessary, 
>how do I get it and how much does it cost?

   I think this was a pretty rare bug. It was caused by a piece of the
Finder's code for adding an rBundle with a window (the one with the
small thermometer that goes across on programs with large rBundles,
like GSHK) that wasn't being relocated. It was doing something like

	sta	$DEAD		;No, I don't recall the exact addr offhand

   Where $DEAD may not have been within the Finder's code, and was
always $DEAD, no matter where that section of the code was located
in memory. For one particular memory configuration I had when I was
writing Rebuilder, that would crash the computer very quickly. Other
systems may be far less affected by it.

   This bug was discovered two and a half years ago, in my last few
days as a summer intern at Softdisk, so I didn't investigate it much
further. I believe it was reported to Apple (fat lot of good that
did). Rebuilder was Softdisk G-S #57 or so; you can give them a call
to see about ordering it.

   As long as you don't add rBundles to your system all the time, this
bug should not affect you. I think.

Nathan Mates

-- 
<*> Nathan Mates http://www.ugcs.caltech.edu/~nathan/      <*>
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