[comp.os.minix] Virtual consoles

dal@syntel.mn.org (Dale Schumacher) (10/11/89)

In article <3631@ast.cs.vu.nl> ast@cs.vu.nl (Andy Tanenbaum) writes:
> Personally, I think a far better and more elgant solution would be
> virtual screens. You simulate N terminals on one. When you hit
> ALT-n, the contents of the screen and replaced by that of terminal ,
> and the keyboard is attached to terminal n. In effect, you are
> timesharing the one screen into n windows. Again, the trick is
> localize everything so that there are no tentacles all over the
> place. It won't be easy. 

I mentioned this some 6-9 months ago, but nobody seemed to care at the
time.  I _HAVE_ implemented a virtual console scheme on the ST version
of Minix.  The interface is very simple, just CTRL+ALT+HOME to switch
to the next virtual console.  The number of consoles is compiled into
the kernel, and each needs it's own screen image, but it works great.
I didn't have much trouble controlling the "tentacle" problem.  In fact,
after discussing the design with Tony Andrews one evening, I wrote the
code and had it working the next day.

\\   /  Dale Schumacher                         399 Beacon Ave.
 \\ /   (alias: Dalnefre')                      St. Paul, MN  55104-3527
  ><    ...umn-cs!midgard.mn.org!syntel!dal     United States of America
 / \\   "What is wanted is not the will to believe, but the will to find out,
/   \\  which is the exact opposite." -Bertrand Russell

ast@cs.vu.nl (Andy Tanenbaum) (10/12/89)

In article <091089A6393@syntel.mn.org> dal@syntel.mn.org (Dale Schumacher) writes:
> I _HAVE_ implemented a virtual console scheme on the ST version
>of Minix.  The interface is very simple, just CTRL+ALT+HOME to switch
>to the next virtual console.  The number of consoles is compiled into
>the kernel, and each needs it's own screen image, but it works great.
>I didn't have much trouble controlling the "tentacle" problem.

If it is indeed relatively simple to do, I am all for it.  I think the
appropriate course of action is to wait for 1.4b (please be patient), and
then see how hard it is to modify that version to add virtual screens.
Since multiple user's are already supported, my naive assumption is that
multiple screens will not be hard.  Input should be trivial.  There are
already multiple input queues for multiple real terminals, so when a
character arrives from the keyboard, the only change is adding a variable
telling the tty driver which "line" it came from, not just assuming line 0.

It is my hope that MINIX-PC and MINIX-ST will begin converging again at
or after 1.4b.  Things like multiple screens are really pretty device
independent.

Andy Tanenbaum (ast@cs.vu.nl)

mwjester@wsucsa.uucp (10/12/89)

In article <091089A6393@syntel.mn.org>, dal@syntel.mn.org (Dale Schumacher) writes:
> 
> ....  I _HAVE_ implemented a virtual console scheme on the ST version
> of Minix.  The interface is very simple, just CTRL+ALT+HOME to switch
> to the next virtual console.  The number of consoles is compiled into
> the kernel, and each needs it's own screen image, but it works great.
> I didn't have much trouble controlling the "tentacle" problem.  In fact,
> after discussing the design with Tony Andrews one evening, I wrote the
> code and had it working the next day.

Dale, could you post this????  Please?

Max Jester
Dept of Computer Science  (Impoverished grad student)
Wichita State U.

# include <disclaimer.std>

7103_300@uwovax.uwo.ca (10/13/89)

It seems to me that rather than building virtual consoles into the
kernel, a nicer solution is to put in the tools that are needed to
make virtual consoles (or windowing systems, or whatever), namely
pseudo-tty's and SIGWINCH, and let the console/window manager run
as a user process.
--
Eric Smith
ersmith@uwovax.uwo.ca
ersmith@uwovax.bitnet