[rescue] newest rescue

Toby Thain toby at telegraphics.com.au
Wed Feb 3 16:54:56 CST 2016

On 2016-02-03 3:27 PM, Romain Dolbeau wrote:
> 2016-02-03 21:09 GMT+01:00 Toby Thain <toby at telegraphics.com.au>:
>> Or memory protection.
> Well, the original 68000 (at the heart of Lisa, Macintosh, Macintosh 512,
> Macintosh Plus, Macintosh SE and so on) didn't really support an MMU or
> memory protection.

I'm not talking about the first generation Macs. And of course A/UX had 
it while Classic MacOS did not.

I have a vague memory that memory protection was _promised_ (but never 
delivered of course) for System 7. Naturally it would have been quite a 
challenging feature to add to the classic system, or perhaps infeasible 
which is why it was quietly dropped.

 > And the original Macintosh only had 128 KiB of memory,
> running multiple programs needing protection from each other wasn't exactly
> high priority on something that was basically a cheap, entry-level Lisa.
> The entry-level Macs were much, much cheaper than the cheapest Sun of the
> same era.

Yet Macs were very common in demanding production applications. Even if 
you had the budget for workstations, on the whole they couldn't run the 
software we were running on Macs - Illustrator, Photoshop, Quark XPress, 
Freehand, etc, in those days.

Before OS X you could choose between "non-Mac Unix, but none of the 
applications you want" or "Mac and applications, but an anachronistic, 
unsafe OS."


> Sun switched to the 68010, like everyone else in the Unix business, to get
> MMU support.
> Cordially,

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