Need help installing libjpeg.so.8

I am trying to host a dedicated server on a machine running Debian 12. I believe I have moved the server.cfg and server_linux.sh files into the proper directories. As a side note: I did have to edit the server_linux.sh file as the binary seems to have changed names from "xonotic-linux64-dedicated" to "xonotic-dedicated" without the script being updated. Anyway, when I run the server script I receive an error that libjpeg.so.8 is missing. Running ldd on xonotic-dedicated confirms this. I have tried installing older versions of libjpeg and creating a simlink but then I receive an error that LIBJPEG_8.0 is missing. I haven't had any luck installing the library from a snapshot either. To those of you running a dedicated server, how do you normally deal with this issue?

I'm guessing you've compiled `xonotic-dedicated` on a machine that has libjpeg.so.8 and copied it to a debian machine which uses libjpeg.so.62.  These libjpeg versions aren't ABI compatible so your binary would need to be linked to the version on the target machine (easiest way is often just to compile on the target machine).

The binary named `xonotic-linux64-dedicated` is the official binary and isn't dynamically linked to libjpeg so it doesn't have this problem.  `xonotic-dedicated` is created by the `make server`  command and will be dynamically linked to whatever libjpeg version is found in the build environment.

I recommend leaving all the files in the Xonotic/ directory, then you can use the rsync updater.
Relevant docs:
https://gitlab.com/xonotic/xonotic/-/wikis/Compiling
https://gitlab.com/xonotic/xonotic/-/wikis/Autobuilds

Edit: the official binaries include their own libjpeg (statically linked) which is because distros can't agree on whether to use libjpeg.so.8 or libjpeg.so.62 so that's the only way to support them all.

Thanks for the response. I believe the problem was that I installed the game via snap, which I guess compiled different binaries that use libjpeg.so.8 instead of 62. I ended up just deleting everything and downloading from the official source, which I really should've done in the first place.

Now the server script can run but exits with a "session lock /home/usr/.xonotic/lock could not be acquired. Please run with -sessionid and an unique session name." It seems like this is supposed to prevent multiple instances of the game from running? I don't actually have that file and it doesn't seem like there are instances of the game running when I run ps aux. Adding the -sessionid flag after the script throws the same error.

Edit: I've noticed that if I run the script at superuser then I get a different error message, later in the script. This one says "You have started a dedicated server but have not created
any server.cfg in your config directory." I would assume that I don't need to run the script as superuser, but I'm not sure why this gets rid of the 'session lock' problem. I've tried rebooting my machine as well but that hasn't helped.

If you've given xonotic a read-only home directory (or userdir) it would fail to create the session lock and other files in `~/.xonotic/`. Running it as root would get around that but best practise is to run it under a normal account with a writeable home directory. Configs and other custom files go in `~/.xonotic/data/` by default.

It does require you to create `~/.xonotic/data/server.cfg` to configure the server a bit, at a minimum you should set `hostname "something other than the default"` in there.

Snap is pretty much ubuntu-specific and ubuntu uses libjpeg.so.8.  The flatpak on flathub.org works on any distro, it uses a different location for files and needs this command to run the dedicated server.

That's good to know, I may try flathub if this method keeps failing me. That makes sense why running as root would fix that one problem, as I think I created these files as root when unzipping. The only questions that I have now is why the script isn't seeing the server.cfg file. I've had it in the right place (~/.xonotic/data/server.cfg) the whole time and modified the hostname and a few other configs.