lxsession-logout allows multiple instances in the same lxsession

[Eliah Kagan]

Binary package hint: lxsession

lxsession-logout allows multiple instances in the same lxsession, while instead, it should probably only be possible to run it once at a time. (Within the same lxsession, I mean. A global prohibition on multiple instances of lxsession-logout would be a bad thing, since there could be multiple concurrent lxsessions running on the same system, either for the same user, or for different users.)

To reproduce this bug, click twice or more, in rapid succession, on the logout button in the LXPanel (in LXDE, as provided by lubuntu-desktop). The desirable behavior would be for the effect to be the same as clicking this button once. However, instead, multiple lxsession-logout instances are loaded. Dismissing one (by clicking Cancel) leaves the others. This behavior is undesirable because there is unlikely to be any useful application for stacking up lxsession-logout menus, and doing so by accident reduces productivity and could be confusing to novices.

Another way that a user could be confused by multiple lxsession-logout instances is if the user tries to logout, but due to his/her computer running slowly, the lxsession-logout menu doesn't come up immediately, so the user clicks it again. That's how I discovered this bug. Lag in drawing the menu is likely to occur only when there are other resource-consumptive processes running, which is also a situation where a user is especially likely to think twice about logging out (and thus especially likely to click Cancel and then suffer the additional lxsession-logout menu).

Oddly, when I double-click on the logout button in my LXPanel, three instances of lxsession-logout get loaded (rather than merely two, as I had expected). I do not know why this is.

I am reporting this bug on a Maverick i386 system with lxsession package version 0.4.4-3. I have also reproduced it on a Maverick amd64 system (same lxsession package version) and a Natty i386 system with lxsession package version 0.4.5-0ubuntu1.

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: lxsession 0.4.4-3
ProcVersionSignature: Ubuntu 2.6.35-24.42-generic 2.6.35.8
Uname: Linux 2.6.35-24-generic i686
NonfreeKernelModules: vmblock vsock vmci vmxnet vmhgfs
Architecture: i386
Date: Wed Dec 29 09:42:02 2010
ExecutablePath: /usr/bin/lxsession-logout
InstallationMedia: Lubuntu 10.10 "Maverick Meerkat" - i386 (20101010)
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: lxsession
XsessionErrors: (polkit-gnome-authentication-agent-1:1491): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Lyn Perrine (walterorlin)]

I get this same behavior in vivid. What is even wierder is if you press the super key and F2 to switch to another workspace you can then continue your bunsiess like lxsession logout doesn't even matter.

[Martin Thornton (thornton-ma)]

I've (hopefully) already fixed this upstream. See http://sourceforge.net/p/lxde/patches/456/

[Lyn Perrine (walterorlin)]

I confirm this was fixed upstram in the released version of lxsession 0.5.2.