From mboxrd@z Thu Jan  1 00:00:00 1970
To: Fans of the OS Plan 9 from Bell Labs <9fans@cse.psu.edu>
From: "Brian L. Stuart" <blstuart@bellsouth.net>
Subject: Re: [9fans] First-timer help 
In-reply-to: Your message of Tue, 19 Jul 2005 11:31:53 +0530 .
	<20050719113153.6a05a689@localhost.localdomain> 
Date: Tue, 19 Jul 2005 20:43:09 -0500
Message-Id: <20050720014352.EUDB8378.ibm70aec.bellsouth.net@p1.stuart.org>
Topicbox-Message-UUID: 6c4f5f0c-ead0-11e9-9d60-3106f5b1d025

In message <20050719113153.6a05a689@localhost.localdomain>, "Martin C. Atkins" 
writes:
>On Mon, 18 Jul 2005 12:45:32 +0200 lucio@proxima.alt.za wrote:
>"Plan 9 way" of dealing with this be to run a multiplexer process
>pre-login, that multiplexes access to /dev/draw(etc) across several
>virtual consoles, and puts a login process in each one? Could that be
>done with the current mechanisms? I guess it would have worked with 8

I've avoided chiming in on this one because the whole thing
seemed a very non-Plan 9 thing and because I've never worked
that way or needed that behavior.  But this suggestion has
piqued my interest.

>>From the user's perspective I'm picturing something along the
lines of a new menu entry in rio that is, say, Suspend.  When
that is selected, the current set of windows all "go away"
(really hidden but no longer accessible from the menu) and
are replaced by a dialog that lets you select a suspended
session or to start a new one.  Both options would require
a password.  As other's have mentioned, this password doesn't
provide any real security.  It's just there to make it hard
for your daughter to save her latest artistic masterpiece
on top of your latest coding masterpiece.

As to implementation, I'm thinking that on boot the multiplexer
starts up running as the machine owner.  As has also been
mentioned, it has a capability to change /dev/user which
it does each time it brings up a new or suspended session.
On creating a new session, it creates a new child process
running as the new user and serves the usual /dev stuff to
the child process.  The only change to rio would be the new
menu entry that would result in a note to the multiplexer
or a message to some other file it serves.  The behavior
could either be controlled by a command line switch or
rio could look for the multiplexer process and do the right
thing when it's found.

I know from experience how dangerous it can be to throw
out ideas as I think them up.  But it's up the flagpole
now.  Anybody interested in saluting or is this one that
would be better off burried?

BLS