Xfce process structure

[Brian J. Tarricone]

On Mon, 07 Jan 2008 01:56:20 +0100 Christian Kastner wrote:
 
> 1) Could the behavior now shown by xfwm4, xfdesktop et al be extended
> to other xfce components as well, or is there a good reason for the
> current behavior?

It's not a matter of extending the behavior.  For example,
xfce-mcs-manager isn't started by the session manager as a part of the
session.  It's started by the first application that needs it.  The MCS
manager daemonises itself, which has the effect of reparenting itself
it init.

> 2) Non-xfce processes (eg firefox) detach as well, but I've seen ps
> output from other (non-desktop) WMs where this is not the case. Is
> this detaching the usual case for DEs, or could this possibly be
> changed too?

It depends on how it's launched.  In order to ensure that apps launched
from xfdesktop or xfce4-panel don't die if xfdesktop or the panel dies,
they're given their own session, which (I think) starts them in their
own process group, which (again, I think) reparents to init.

I don't really think we can "fix" this for you.  However, all of these
applications should quit when the X server goes down.  Can't
libpam-mount wait until after X quits before trying to unmount your
homedir?  That seems to be the more logical course of action, as you
could say that technically your login session doesn't actually
terminate until X does.

Even then, though, there might be a race condition to see who notices X
quitting first: all of the X apps, or libpam-mount.  What you *really*
want is something like ConsoleKit to trigger the unmount, but I don't
know if that's possible currently.

Another option, assuming you're using Linux, is to modify libpam-mount
to do a 'lazy' unmount, equivalent to the '-l' parameter to 'umount'.
That way the unmount should effectively get "scheduled" to happen once
all files on the volume are closed.

	-brian