reopening the session management discussion...

[Brian J. Tarricone]

On Tue, 2 Sep 2008 09:08:50 +0100 Olivier Fourdan wrote:

> On Mon, Sep 1, 2008 at 11:16 PM, Brian J. Tarricone
> <bjt23 at cornell.edu> wrote:
> > On Mon, 1 Sep 2008 22:11:31 +0100 Olivier Fourdan wrote:
> >
> >> On Wed, Aug 27, 2008 at 12:27 PM, Brian J. Tarricone
> >> > * App can never "accidentally" fall out of the session due to a
> >> > crash (I guess I'm the biggest offender here). App will always be
> >> > started when the DE starts unless the user disables it.
> >>
> >> Inmplementing SmRestartImmediately in xfce4-session would solve the
> >> problem without loosing the flexibility of session management.
> >
> > Well, who wants to do that?  Benny doesn't seem to be around, and I
> > feel like there must have been a reason why he didn't implement it
> > in the first place.
> 
> I reallty see no reason other than no time or interest.

I looked through the xfce4-session source for maybe a code comment
explaining the omission, but I didn't see anything.  I also thought
Benny had talked about it on the ML at some point, but a search of the
archives didn't yield anything (perhaps I just suck).

> BTW, I totally
> agree, xfce4-session needs work, so we either make it evolve or remove
> it entirely. I do not think we can keep unmaintained code around
> anyway.

Yeah, it's a problem, certainly.  Maybe I'll take a look at it after
I'm less unhappy with xfdesktop.  And I'll look at that parallel
startup patch.

> > And note that implementing this will break your second issue below
> > without even more work -- if we implement SmRestartImmediately, or
> > even SmRestartAlways, we need to also implement new UI to let the
> > user remove things from the session, since otherwise there's no way
> > to kill/replace components without editing the session file
> > manually.
> 
> Not really, there are ways to do this cleanly, like change the restart
> hint depending on how the app exited (for example,
> SmRestartImmediately by default, SmRestartIfRunning when killed with
> TERM. This is how it works with other WM for example, as ICCCM" allows
> to replace a running WM (feature implemented in xfwm 4.6).
> 
> What we want is to restore apps that dies unexpectidly, not force the
> user on xfdesktop/xfwm4/xfce4-panel.

Right, of course.  But still, the user has to go to a shell and do
'killall -TERM xfdesktop' or whatever.  Not quite as friendly as
clicking few buttons in the autostarted apps dialog.  And sure, we can
GUIify it either way, but the autostarted apps dialog exists and works
already.

> >> In other words, I do not think that using a separate mechanism to
> >> start some of the components is the good solution, unless we have
> >> some sort of standard (ie, ppl can replace xfwm4 with compiz,
> >> xfdesktop with nautilus, etc. in a way that is not xfce specific)
> >
> > Well we currently don't have a great way of letting people do this
> > anyway -- at least not a way that doesn't require a 'magic'
> > sequence of steps that you have to know to get it to work (e.g.,
> > killall xfdesktop, run nautilus, make sure apps that you want in
> > your session are running, then log out and save your session).  At
> > least using the autostart method is fairly straightforward (open
> > autostart editor, de-select or remove the app you don't want, and
> > add the app you do want), and I would imagine people might be able
> > to figure it out for themselves even.
> >
> > The session manager approach also makes it very hard for us to
> > change the default session if the user has changed a custom
> > session.  We couldn't use SM support for xfce4-settings-helper
> > because there's no way for a 4.4 user with a custom session to
> > upgrade to 4.6 and magically get xfce4-settings-helper in their
> > session (so we used autostart instead).
> >
> > I still just don't see how SM is better for us than autostart right
> > now, especially given xfce4-session's limitations.
> 
> But you have toi think of the whole picture, not just xfce. Think of
> people using xfwm4 with gnome for exampme, if xfwm4 does not register
> to the session, it will never be restored. Session management is the
> standard way of saving/restoring apps between sessions.

Sigh, yeah, that's true, though there seems to be some amount of
sentiment in the community at large that X11 SM should be replaced.  Of
course, no one's come up with even a proposal for a replacement, let
alone a sample implementation, so SM is, as you say, the standard.

It's my hope that I'll have some time to play with xfce4-session before
beta2, but... no promises.

	-b