[comp.sys.mac.misc] Mac OS versus A/UX, Who runs under who?

Garance_Drosehn@mts.rpi.edu (Garance Drosehn) (11/04/90)

In article <3818@idunno.Princeton.EDU> 
           bskendig@set.Princeton.EDU (Brian Kendig) writes:
>            Besides, Apple's tactics against IBM
> (that a GUI on a PC is an add-on, where it's built into the Apple) can
> be used against it here -- if you want A/UX you have to buy it and run
> it on top of the Mac operating system, whereas the NeXT is built
> around Unix to begin with  ...(etc)...

Without bothering with the religious war over which computer a certain 
individual that most of us do not know should buy, I don't think the above 
is quite right.  Please correct me if I'm wrong, but...

I thought that A/UX, when it's running, is the operating system in control 
of the machine.  The Mac OS, if it is running with A/UX, runs as a process 
under A/UX.  As such, it would not be correct to say that A/UX is running 
on top of the Mac OS.  True?  False?  True on somedays but False on others?

Garance_Drosehn@mts.rpi.edu
ITS Systems Programmer
Rensselaer Polytechnic Institute; Troy, NY.  USA

c60a-cz@danube.Berkeley.EDU (Donald Burr) (11/04/90)

In article <{'!^2|*@rpi.edu> Garance_Drosehn@mts.rpi.edu (Garance Drosehn) writes:
>Without bothering with the religious war over which computer a certain 
>individual that most of us do not know should buy, I don't think the above 
>is quite right.  Please correct me if I'm wrong, but...
>
>I thought that A/UX, when it's running, is the operating system in control 
>of the machine.  The Mac OS, if it is running with A/UX, runs as a process 
>under A/UX.  As such, it would not be correct to say that A/UX is running 
>on top of the Mac OS.  True?  False?  True on somedays but False on others?

A/UX is a totally seperate OS from the Mac OS.  When you launch A/UX from

the Mac finder, it does a warm-boot into the A/UX operating system -- total
new kernal, new OS, etc.  The A/UX has its own Finder, which is both A/UX
and Mac compatible.  Really nicely integrated, Apple did a good job on this
one.
______________________________________________________________________________
Donald Burr, c60a-cz@danube.Berkeley.edu  | "I have a seperate mail-address
University of California, Berkeley        | for flames and other such nega-
Majoring in Computer Science              | tive msgs; it's called /dev/null."

andyp@treehouse.UUCP (Andy Peterman) (11/05/90)

In article <{'!^2|*@rpi.edu> Garance_Drosehn@mts.rpi.edu (Garance Drosehn) writes:
>I thought that A/UX, when it's running, is the operating system in control 
>of the machine.  The Mac OS, if it is running with A/UX, runs as a process 
>under A/UX.  As such, it would not be correct to say that A/UX is running 
>on top of the Mac OS.  True?  False?  True on somedays but False on others?

True all of the time.  When the A/UX kernel starts up, it is completely
in charge of the machine.  It then starts up the MacOS as a process
along with MultiFinder and an 8 meg virtual memory space.  The MacOS then
brings up Finder as its shell.  As such, anything running under the
MacOS is treated as just another process.  In fact, you can totally bomb
a program and A/UX keeps running, a VERY nice feature.  After the
program bombs, you can sometimes recover within the MacOS, or "restart",
which simply kills the MacOS process and logs you out, all without
affecting any other A/UX process, except for stealing a lot of processor
time.

-- 
Andy Peterman                       |   Opinions expressed
treehouse!andyp@gvgpsa.gvg.tek.com  | are definitely those of
(916) 273-4569                      |      my employer!

lantz@Apple.COM (Bob Lantz) (11/05/90)

Garance_Drosehn@mts.rpi.edu (Garance Drosehn) writes:

>I thought that A/UX, when it's running, is the operating system in control 
>of the machine.  The Mac OS, if it is running with A/UX, runs as a process 
>under A/UX.  As such, it would not be correct to say that A/UX is running 
>on top of the Mac OS.  True?  False?  True on somedays but False on others?

Right! The Macintosh environment runs on top of A/UX.

>Garance_Drosehn@mts.rpi.edu
>ITS Systems Programmer
>Rensselaer Polytechnic Institute; Troy, NY.  USA

Bob Lantz
A/UX Team

dce@smsc.sony.com (David Elliott) (11/05/90)

In article <627@treehouse.UUCP> andyp@treehouse.UUCP (Andy Peterman) writes:
>a program and A/UX keeps running, a VERY nice feature.  After the
>program bombs, you can sometimes recover within the MacOS, or "restart",
>which simply kills the MacOS process and logs you out, all without
>affecting any other A/UX process, except for stealing a lot of processor
>time.

Wait.  I don't think you mean "logs you out", at least not in the Unix
sense of the term.  I mean, if a bombed MacOS program actually logged
me out of my A/UX session, it would be only slightly better than
having the whole system go down.

Of course, if your login session starts MacOS and no other processes,
it would log you out, but I'm not sure that that would utilize the
advantages of A/UX.

rmtodd@servalan.uucp (Richard Todd) (11/05/90)

dce@smsc.sony.com (David Elliott) writes:
>In article <627@treehouse.UUCP> andyp@treehouse.UUCP (Andy Peterman) writes:
>>program bombs, you can sometimes recover within the MacOS, or "restart",
>>which simply kills the MacOS process and logs you out, all without

>Wait.  I don't think you mean "logs you out", at least not in the Unix
>sense of the term.  I mean, if a bombed MacOS program actually logged
>me out of my A/UX session, it would be only slightly better than
>having the whole system go down.

  Well, it depends on exactly how you logged in on the console.  The login
window allows you a choice of "login sessions".  If you choose the "console
emulator" choice, you get basically a generic glass tty emulation on the
console and your choice of login shell running on /dev/console.  If you
chose the 32-bit or 24-bit MacOS session type, it effectively acts as if
your login shell was /mac/bin/mac32 (or /mac/bin/mac24) and starts up
the appropriate MacOS emulator.  Now, you can be in MacOS without having
chosen the 32 or 24-bit session from the login window; one can login to
the Mac in "console emulator" mode and run mac32 or mac24 from your shell
prompt.
  Now, if you had actually logged into the MacOS environment, then yes if 
MacOS goes down it logs you all the way out.  If you first get a shell 
running on the console and then start up MacOS, when it fails you just
get dumped out to your shell prompt on the console.  

>Of course, if your login session starts MacOS and no other processes,
>it would log you out, but I'm not sure that that would utilize the
>advantages of A/UX.
  You mean being able to use MacOS and A/UX programs simultaneously?  Yeah,
you can always do that.  Whenever mac32 or mac24 start up, they always start
up two MacOS programs under MultiFinder: Finder and CommandShell.  
CommandShell allows multiple text windows on the screen, each one talking to
a different pty with your favorite Unix shell running on it (sorta the poor
man's xterm :-).  
--
Richard Todd	rmtodd@uokmax.ecn.uoknor.edu  rmtodd@chinet.chi.il.us
	rmtodd@servalan.uucp
6 days until the season premiere of WISEGUY!

andyp@treehouse.UUCP (Andy Peterman) (11/05/90)

In article <1990Nov5.004631.20821@smsc.sony.com> dce@smsc.sony.com (David Elliott) writes:
>
>In article <627@treehouse.UUCP> andyp@treehouse.UUCP (Andy Peterman) writes:
>>which simply kills the MacOS process and logs you out, all without
>
>Wait.  I don't think you mean "logs you out", at least not in the Unix
>sense of the term.  I mean, if a bombed MacOS program actually logged
>me out of my A/UX session, it would be only slightly better than
>having the whole system go down.

It depends on how bad the bomb is.  If its just an application bomb
where under the normal MacOS you could ExitToShell and keep running,
then the same holds true under A/UX.  But if you completely bomb the
system where normally you would end up rebooting, then yes, you are
"logged out".  I believe this is due to the fact that when you log in,
you're actually logging in to the MacOS and the CommandShell is simply a
secondary shell.  If you bomb MacOS, not just some application, then
A/UX has no other choice than to kill it, which logs you out.  Any other
processes, such as anyone else logged in through the serial ports, will
continue normally.

-- 
Andy Peterman                       |   Opinions expressed
treehouse!andyp@gvgpsa.gvg.tek.com  | are definitely those of
(916) 273-4569                      |      my employer!

russotto@eng.umd.edu (Matthew T. Russotto) (11/05/90)

In article <1990Nov5.004631.20821@smsc.sony.com> dce@smsc.sony.com (David Elliott) writes:
>
>Wait.  I don't think you mean "logs you out", at least not in the Unix
>sense of the term.  I mean, if a bombed MacOS program actually logged
>me out of my A/UX session, it would be only slightly better than
>having the whole system go down.
>
>Of course, if your login session starts MacOS and no other processes,
>it would log you out, but I'm not sure that that would utilize the
>advantages of A/UX.

You are correct-- though the documentation says 'logs you out', as do the menu
items, if you start up MacOS from the console rather than from the Mac
Login program, it will return you to the console.  You can use the full power
of A/UX without going to the console, however, by using the 'CommandShell'
application (roughly equivalent to a SunTools shelltool, or xterm under X)
--
Matthew T. Russotto	russotto@eng.umd.edu	russotto@wam.umd.edu
Tax the rich, and feed the poor -- until there are, rich no more.