$ /tmp/doomseeker/doomseeker
[19:42:14] Starting Doomseeker. Hello World! :)
[19:42:14] Setting up data directories.
[19:42:14] Cache directory: /home/wub/.cache/doomseeker
[19:42:14] Config directory: /home/wub/.config/doomseeker
[19:42:14] Data directory: /home/wub/.local/share/doomseeker
[19:42:14] Attempting to load plugins from directory: /home/wub/.local/share/doomseeker/engines
[19:42:14] Attempting to load plugins from directory: /tmp/doomseeker/engines
[19:42:14] Loaded plugin: "Chocolate Doom"!
[19:42:14] Loaded plugin: "Odamex"!
[19:42:14] Loaded plugin: "Sonic Robo Blast 2"!
[19:42:14] Loaded plugin: "Turok 2 Remaster"!
[19:42:14] Loaded plugin: "Zandronum"!
[19:42:14] Listening to Zandronum's LAN servers broadcasts on port 15101.
[19:42:14] Initializing configuration file.
[19:42:14] Setting INI file: /home/wub/.config/doomseeker/doomseeker.ini
[19:42:14] Loading translations definitions
[19:42:14] Reading localizations definitions file: translations.def
[19:42:14] Initializing IP2C database.
[19:42:14] Initializing passwords configuration file.
[19:42:14] Initializing configuration for plugins.
[19:42:14] Initializing IRC configuration file.
[19:42:14] Setting IRC INI file: /home/wub/.config/doomseeker/doomseeker-irc.ini
[19:42:14] Starting refreshing thread.
[19:42:14] Preparing GUI.
[19:42:15] Please wait. IP2C database is being read. This may take some time.
[19:42:15] Parsing IP2C database: /home/wub/.local/share/doomseeker/IpToCountry.dat
[19:42:15] Init finished.
================================
[19:42:15] Total refresh initialized!
[19:42:15] IP2C database read in 187 ms. Entries read: 158337
[19:42:15] IP2C parsing thread has finished.
[19:42:15] IP2C parsing finished.
[19:42:18] Finished refreshing. Servers on the list: 514 (+1 custom, +0 LAN). Players: 94.

Quote from intox8907
Oh, god! I'm very sorry. I didn't want anyone to spend hours trying to just compile it! I should have made clear the steps...

#!/bin/sh
qemu-system-x86_64 -m 4096 -drive if=virtio,file=openbsd.img,format=raw \
  -cdrom cd64.iso -enable-kvm -smp 4 \
  -nic user,model=virtio

Quote from intox8907
I also received the suggestion of starting up the UDP transaction and then monitoring it via tcpdump, but I haven't done something like this before, so I will need to read a bit first.

Quote from WubTheCaptain
This was done, see doomseeker.pcap attachment. You can open it with Wireshark.

Quote from WubTheCaptain
Also fyi that OpenBSD ships with zlib 1.2.3 in base system, which is older.

$ doas tcpdump -s 65535 -i vio0
tcpdump: listening on vio0, link-type EN10MB

^C
0 packets received by filter
0 packets dropped by kernel

doas tcpdump -s 65535 -w /tmp/doomseeker.pcap

1. UDP packets are sent to DNS servers and received to resolve master.zandronum.com and doomseeker.drdteam.org hostnames to IPs.
   
2. Doomseeker starts HTTP and HTTPS handshakes with doomseeker.drdteam.org to check for IP2C update.
   
3. TCP connection to doomseeker.drdteam.org gets reset as the request is completed.

Quote from intox8907
Confirmed that using latest checkout of Doomseeker 1.2~beta and using the FORCE_QT4 CMake option also fixes the problem. There is one bit though:

```
/home/me/doom/doomseeker/src/core/localizationinfo.cpp:75:23: error: calling
      'split' with incomplete return type 'QStringList'

Quote from intox8907
I checked out the 1.1-p1 tag from the Mercurial repository, installed Qt4 and used the FORCE_QT4 CMake option. Doomseeker compile successfully and now registers successfully with the master servers, so it is probably a Qt5 problem.

Quote from Pol M
header.length > 65536

Quote from WubTheCaptain
Looks like that might be a workaround, although we really should be fixing this issue by fixing 0003531.

Quote from Wub

Also, not in favor of "magic values".

Quote from Zalewa

Is the problem this ticket refers to fixed now?

Quote from WubTheCaptain
I will open a seperate ticket about this hack to remember to remove it later