reopening the session management discussion...

[Olivier Fourdan]

Hi,

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
>> > A while ago, I suggested that perhaps xfwm4, xfdesktop, xfce4-panel,
>> > etc. shouldn't use X11 session management to ensure startup, but
>> > just use the fd.o autostart mechanism instead.  I believe I was
>> > shot down at the time -- I think Olivier was opposed to the idea
>> > for some reason that I can't remember.
>> >
>> > However, I still see this as a good idea:
>> >
>> > Pros:
>> >
>> > * 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. 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.

> 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.

>
>> 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.

Cheers,
Olivier.