Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!brutus.cs.uiuc.edu!apple!apple.com!chewy
From: chewy@apple.com (Paul Snively)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Need info on multitasking capabilities on the mac
Message-ID: <5338@internal.Apple.COM>
Date: 21 Nov 89 20:22:08 GMT
Sender: usenet@Apple.COM
Organization: Apple Computer, Inc.
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In article <9035@hoptoad.uucp> tim@hoptoad.uucp (Tim Maroney) writes:
> Protected memory is
> not a requirement for asynchronous (or time-sliced or pre-emptive)
> multitasking.  It's very nice to have with *any* kind of multitasking,
> or even with single-tasking systems with a division between OS and user
> task, but it's by no means necessary.  It's just a good thing for
> system reliability, particularly on development systems where code in
> progress is very likely to sometimes step all over the OS or other
> tasks.  Unfortunately, Apple doesn't think it's important, despite
> near-unanimity in the developer community to the contrary.
> -- 
> Tim Maroney, Mac Software Consultant, sun!hoptoad!tim, tim@toad.com

I'm curious, Tim, as to precisely when any entity called Apple revealed to 
you that it doesn't think that protected memory is important.

I'd wager large sums of money that what you REALLY mean is 
"MultiFinder/MacOS doesn't support protected memory, therefore whoever is 
ultimately responsible for the engineers who wrote MultiFinder/MacOS must 
not think that protected memory is important."

My personal opinion is that there was no good way to implement protected 
memory for the MacOS on the few machines that we have that are even 
guaranteed to have a PMMU chip, and that while we were able to hack 
multitasking comparatively well, we would have created far more problems 
with trying to implement protected memory on top of the current OS.

It seems like a lot of what's being asked for will have to wait for a 
brand-spanking new OS.  That wouldn't be a bad thing (also in my opinion) 
but neither can I make any promises.  Sorry.

__________________________________________________________________________
Just because I work for Apple Computer, Inc. doesn't mean that they 
believe what I believe or vice-versa.
__________________________________________________________________________
C++ -- The language in which only friends can access your private members.
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