Stop (GUI) server in Linux ?

[pcar75]

Bonjour,
On my dual boot PC, I can shutdown Jamulus server in Windows 10. However I can't do that in Linux, because I believe it installs itself as a service. Is there a nicer (GUI) way of shuting down Jamulus server, instead of running a script or terminal with killall -I "jamulus" ?

Context : dual Boot PC : Windows 10 / Ubuntu Studio 22.04.1 LTS (Plasma KDE).
On Windows
Jamulus server (3.9.1) with GUI
Menu > Window > Exit (Ctrl+Q) : OK terminates process & threads
X Button : OK terminates process & threads
On Ubuntu Studio 22.04.1 LTS
Jamulus server (3.9.1) with GUI and Icon in system tray bar
Menu > Window > Exit (Ctrl+Q) : Hides GUI only
X (Close) Button : Hides GUI only
Sys tray Exit (Icon menu buttons = Exit, Show, Hide...) : Hides GUI if it was visible ( ~ Exit ICON menu).

EDIT : added precision : Ubuntu Studio 22.04.1 LTS and Qt is 5.15.3 as mentioned below (rdica).

[rdica]

I installed the deb on my Ubuntu Studio 22.04 DAW and I dont see a systemd service file. Their are two GUI shortcuts, one starts the client, one starts the server with jamulus -s. There's no service to stop once you've stopped the GUI server.

Interestingly enough, and I think it may be a bug, but I cannot stop the GUI server client. It seems to ignore exit. I had to killall jamulus from CLI.

[rdica]

[pljones]

Thanks for confirming.

[rdica]

Fired up an instance of Xubuntu (XFCE4) 22.04, installed 3.9.1 deb, ran the server from menu and also from CLI, and in both cases the server exited correctly.

[pljones]

Thanks for trying that, too. Good to hear. That does narrow things down.

[rdica]

Spun up a Kubuntu 22.04 instance (not Ubuntu Studio) and saw the same behavior shown in Ubuntu Studio.

[pljones]

So far, no one else has commented running Linux but not running Ubuntu Studio 22.04 LTS. I can't think what Ubuntu Studio would have done but it would be good to hear other experiences. Could others with this issue please comment.

[pcar75]

So, to my understanding , the problem seems to be related to KDE vs Qt vs applications' setup and use of these ... (not Ubuntu).
An initial web search points to somewhat similar problems (centered around KDE). I will continue to search the web for more / better info.

Meanwhile, more details ...
@rdica Can you confirm the same specs ?

uname -a
Linux user-kubuntu-pc 5.15.0-60-generic #66-Ubuntu SMP Fri Jan 20 14:29:49 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux

lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 22.04.1 LTS
Release: 22.04
Codename: jammy

In destop's System Settings > About this System
Operating System: Kubuntu 22.04
KDE Plasma Version: 5.24.4
KDE Frameworks Version: 5.92.0
Qt Version: 5.15.3
Kernel Version: 5.15.0-60-generic (64-bit)
Graphics Platform: X11
(...)

N.b.: I installed Ubuntu Studio 22.04 LTS packaging over Kubuntu 22.04 LTS.
I did follow a specific install referenced in a video on Ubuntu Studio* page, that can allow a low-latency kernel and can "grub-boot" it. However, having seen no major difference between generic and low-latency for jamulus sessions , I normally boot to generic kernel.

*Mauro Gaspari video tutorial with
https://frontpagelinux.com/tutorials/easily-install-jack-audio-with-ubuntu-studio-installer/
(except nothing special for Carla as I did not plan on using it)

• Enable realtime process priority

and
Select packages to install :

• linux-lowlatency
• ubuntustudio-lowlatency-settings
• ubuntustudio-performance-tweaks

[rdica]

The kernel versions have no bearing. On the non-Ubuntu Studio installs I used the default generic kernel AND the lowlatency kernel.

I suspect KDE/kwin as pkg'd by Ubuntu, still thinking how I can isolate and further test/troubleshoot...

[rdica]

I spun up the Fedora 37 KDE spin, installed build deps, and compiled 3.9.1 from src.
QT 5.15.8
gcc 12.2.1
KDE 22.12.2

Same behaviour!
Fedora seems to default to Wayland, I saw one message in the terminal I started Jamulus from, and it was caused by clicking
"Show Jamulus server" from tray icon.

Had to ctrl+c in the terminal to terminate the process.

[rdica]

I forgot to note, my installation of Ubuntu Studio 22.04 uses Xorg, not Wayland.

[pcar75]

I posted this questions in Ask Ubuntu, to further search for a solution.
https://askubuntu.com/questions/1455310/cannot-terminate-jamulus-server-under-kde

[pcar75]

From a few observations ...

• rdica's trace : "CServerDlg: bSystemTrayIconAvailable=1"

• pljones : "The event received line means that Qt is telling Jamulus the user has asked to close the app. Jamulus says "OK go ahead". Again, it's down to Qt to actually end the application.

• There is an application called "Discover" that also has an icon in the system tray. When I menu-cliked it to Exit, a pop-up appeared to verify that I really wanted to Exit this program. This has never happened with the Jamulus server system tray icon's Exit.

Is it possible to test a version that does not install it's "icon/etc." in the system tray ? Just to see if this could rule out a now different behavior between KDE and Qt. Sorry, but I'm not Linux-savy enough to install and test it on my system without breaking something.

[pljones]

src/serverdlg.cpp around line 35, change

bSystemTrayIconAvailable = SystemTrayIcon.isSystemTrayAvailable();

to

bSystemTrayIconAvailable = false; //SystemTrayIcon.isSystemTrayAvailable();

then rebuild with make distclean; qmake && make and run with ./Jamulus -s

[rdica]

I recompiled using the above, lo and behold, exiting actually worked. There was no tray icon, which was expected.
ctrl-q and alt-F4 both worked as well as exiting via the GUI.

[pcar75]

@rdica Thanks for testing my hypothesis :-)

@pljones I think I should make this into a bug report. Do you agree ?

[pljones]

It's not a bug in Jamulus. You can log a feature request to make it possible to turn off iconise to system tray. :)

(Me, I'd rather the feature was totally removed, but I'm like that.)

[rdica]

I filed an issue from this discussion.

[pcar75]

@rdica Thanks ! To me, I would rather classify it as a bug or at least undesirable behavior of the system tray icon ...
Issue = Current KDE prevents Server GUI from exiting #3016
Closing this one.