Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!umich!samsung!think!mintaka!bloom-beacon!eru!luth!sunic!tut!kaarne!mn87537
From: mn87537@kaarne.tut.fi (Nordberg Marko Johan Kalervo)
Newsgroups: comp.sys.amiga
Subject: Re: More Mac BS
Message-ID: <12308@etana.tut.fi>
Date: 8 Apr 90 20:48:08 GMT
References: <86162309190@andrews.edu>
Sender: News@tut.fi
Reply-To: mn87537@kaarne.tut.fi (Nordberg Marko Johan Kalervo)
Organization: Tampere University of Technology, Finland
Lines: 22

In article <86162309190@andrews.edu> andrew@andrews.edu (Andrew Gillham) writes:
>
>Well, since everyone else is talking about Macs, I thought I ask a 
>question.  A friend of mine told me that one problem with making the mac
>system software multi-tasking, is that most mac software runs in supervisor
>mode. (or is written using privileged instructions?)
>Does anyone know if this is true?  And what effect would this really have?

This is true. There is an article in november issue of Byte which tells
how virtual memory is implemented in Mac os v7.0 and problems with it.

>Alright, now for something about the Amiga..
>When people pop 68010's in their Amiga's and the movesr.xx  instruction
>breaks, that's because the Amiga OS runs in user mode?  

Amiga OS runs in supervisor mode and other programs should run in user mode.
User mode programs running in 68010, 68020 etc. will cause problems if they
use movesr.xx instruction.

_______________________________________________________________
! Marko Nordberg, Atomik. 6A19, 33720 TRE  !  "Puhun omiani"  !
! mn87537@tut.fi, (931) 185 757            !         -MN-     !