Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!math.lsa.umich.edu!hyc
From: hyc@math.lsa.umich.edu (Howard Chu)
Newsgroups: comp.sys.atari.st
Subject: Re: Anyone know about MT C-shell?
Keywords: MT C-shell
Message-ID: <11028@stag.math.lsa.umich.edu>
Date: 19 Feb 90 06:11:48 GMT
References: <20967@ditka.UUCP>
Sender: news@math.lsa.umich.edu
Reply-To: hyc@math.lsa.umich.edu (Howard Chu)
Organization: University of Michigan Math Dept., Ann Arbor
Lines: 38
UUCP-Path: {mailrus,umix}!um-math!hyc

In article <20967@ditka.UUCP> rcb@ditka.UUCP (Roy Bixler) writes:
>So, I only know what the advertisement said about MT C-shell, which was
>that it is multi-user, multi-tasking, runs GEM programs and as an
>option, UUCP is available.  Sounds good (maybe too good).  Is it really
>multi-user, multi-tasking? I doubt this because someone told me that he
>didn't think the Motorola 68000 chip had memory protection mode and, in
>light of that, it would be impossible for a 68000 to run multi-user. 
>Also, does the MT C-shell come with any Unix utilities and, if so, which
>ones? What do people think of it? Is it just as good to get a public
>domain, multi-tasking kernal such as MX2?

My big gripe with MX2, besides the fact that it stopped working when I got
TOS 1.4 installed in my machine, was that it didn't propagate your environment
to the spawned processes. (My next gripe was that it's written in Modula-2
and it's far from apparent how to modify it to this poor C programmer/Unix
hacker...  }-)

Hm. Granted, a 68000 running at 8MHz pushes as many MIPS as a Vax 750,
do you *really* want to turn your machine into a multi-user host? (I've
never understood the BBS oprerator mentality, sorry.  Why the *hell*
would I want to turn loose a bunch of unfamiliar hackers on the  machine
I've slaved over for so long? Why would I want to donate a phone line or
two for other people to use, dedicate an expensive modem to their use, etc.?
I shelled out a lot of hard-earned cash for a machine for *me* to use, let
those hackers hack on their own machines...)

But, to try to answer the question, no, the 68000 doesn't support
memory protection. It's not *impossible* to run multi-user, just unwise,
unless you're very certain about the folks you allow to be users. And
that just covers the "malicious intent" side of things, you still have
to worry about runaway programs that accidentally romp thru memory and 
trash everything that everyone else was doing.

Rethink what you're trying to do. The ST is a *personal* computer. You
don't want to have other people using it, you're supposed to have it
all to yourself...
--
  -- Howard Chu @ University of Michigan