Idle Users

[Bob Rasmussen]

On Thu, 17 Jun 2004, Fairlight wrote:

> Simon--er, no...it was Bob Rasmussen--said:
> >
> > I can address the issue of preventing the problem from occurring. If you
> > run Anzio Lite or AnzioWin (our products) as your telnet client, you can
> > "disable quit" in Edit:Advanced options. This disables both the "X" box
> > and the File:Quiet menu item. The user would then quit by exiting from
> > their session at the Unix level.
>
> Why not just handle the WM event gracefully?
>
> I just tested something with Perl/Tk.  If I bind to <Destroy> on the
> top-level window, when I click on the 'X' icon, I -do- get a destroy event.
> ...
> So if the facilities are there as they must be in C for pTk to accomodate
> this behaviour, why would anyone take half-measures?  Just politely close
> out the session in the ssh or telnet protocols before exiting.  Seems
> simple enough, and frankly seems like the correct way of doing it.

Handling the WM event is exactly what I am doing. And closing the telnet
or SSH session gracefully is ALSO what I am doing. The problem comes when
the host's application does not shut down in response. I *think* this is
due to the "hangup" signal (SIGHUP), which is generated by the telnetd or
sshd, is trapped or ignored at some level. Then what? Because of this
possibility, I give users and administrators the option of disabling quit.

I have brainstormed on how I might improve on this situation. Both telnet
and ssh allow the sending of several arbitrary signals to the server.
Maybe I could offer an option where, on WM_QUIT, Anzio would send a hangup
signal to the server. If the server trapped out the hangup, everything
would stay running. If the hangup was handled normally, the server would
close its end of the connection, and Anzio would exit gracefully.

Reactions?

Regards,
....Bob Rasmussen,   President,   Rasmussen Software, Inc.

personal e-mail: ras at anzio.com
 company e-mail: rsi at anzio.com
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