Xref: utzoo comp.sys.amiga:23816 comp.sys.amiga.tech:2077
Path: utzoo!attcan!uunet!ncrlnk!ncrcae!ece-csc!mcnc!rutgers!bpa!cbmvax!ditto
From: ditto@cbmvax.UUCP (Michael "Ford" Ditto)
Newsgroups: comp.sys.amiga,comp.sys.amiga.tech
Subject: Re: Next Amiga system
Summary: Unix under Exec?   Exec under Unix?   Hmm... let me count the ways
Keywords: real-time unix
Message-ID: <4964@cbmvax.UUCP>
Date: 8 Oct 88 03:38:16 GMT
References: <3678.AA3678@heimat> <2756@sugar.uu.net>
Reply-To: ditto@cbmvax.UUCP (Michael "Ford" Ditto)
Organization: Commodore Technology, West Chester, PA
Lines: 43

In article <2756@sugar.uu.net> peter@sugar.uu.net (Peter da Silva) writes:
>Give the man a cigar. Yes, this is what I want to do. To be precise, I want
>to run UNIX *under* AmigaDOS. I want a real-time UNIX.

Running Unix under AmigaDOS would certainly not make it real-time Unix; it
would be less real-time than if it were running directly on the machine.
If a real-time Unix did exist for the Amiga, then it would make more sense
to run Exec under Unix than the other way around.

>							 This technology has
>been demonstrated (BSD under Mach, for example) and I believe that everything
>UNIX needs is provided by AmigaDOS.

	... except reliability.  It could work, but it would give me
the willies.  All that nice memory protection gone to waste as soon as
you run a buggy AmigaDOS program.  (Oops!  Guru meditation!?  Now I
have to sit through another fsck!)

Another possibility is to run Exec under Unix in a virtual machine...
sounds awful, but that's what the Ms.Dos folks do with VP/IX and such.
Real-time would be almost out of the question if this were done under
"standard" Unix.

Yet another possibility is to run them almost side-by-side -- have Unix at
the core, but Exec tasks could be Unix processes.  The Exec tasks could all
run in the same context (like the current Exec) or in separate memory spaces
with a big chunk of MEMF_PUBLIC shared memory.  If enough of the graphics
library & intuition were in the Unix kernel, they could achieve real-time
response.  And the best part ... if you run a buggy program, the worst
that would happen is you might crash *one* of your virtual Amigas.  (So
you just go type "!!" on Unix and your in business again :-).

And there are at least half a dozen other interesting ways to combine Unix
and Amiga software...  the above is just idle speculation.  I agree with
Peter da Silva that something really exciting could and should be done
in this area, but I suppose we have to start with the essentials.
-- 
					-=] Ford [=-

"The number of Unix installations	(In Real Life:  Mike Ditto)
has grown to 10, with more expected."	ford@kenobi.cts.com
- The Unix Programmer's Manual,		...!sdcsvax!crash!elgar!ford
  2nd Edition, June, 1972.		ditto@cbmvax.commodore.com