XInitThreads

[ctrueden]

The ImageJ Launcher calls XInitThreads on Linux when not in headless mode, so that 3D graphics libraries like Vulkan work as needed:

#ifdef __linux__
  void (*xinit_threads_reference)();
  ...
  // This call is neccessary on Linux to avoid X11 errors when using
  // various 3D graphics APIs like Vulkan or OpenGL.
  if (!headless) {
    void *libX11Handle = dlopen("libX11.so", RTLD_LAZY);
    if(libX11Handle != NULL) {
      debug("Running XInitThreads\n");
      xinit_threads_reference = dlsym(libX11Handle, "XInitThreads");

      if(xinit_threads_reference != NULL) {
        xinit_threads_reference();
      } else {
        error("Could not find XInitThreads in X11 library: %s\n", dlerror());
      }
    } else {
      error("Could not find X11 library, not running XInitThreads.\n");
    }
  }
#endif

Should Jaunch also do this? Maybe an optional directive? It would be a directive that does not switch the result from LAUNCH to CANCEL.

[imagesc-bot]

This issue has been mentioned on Image.sc Forum. There might be relevant details there:

https://forum.image.sc/t/jaunch-a-new-java-launcher-test-fiji-with-java-21/92058/1

[kephale]

Is there a reason not to run XInitThreads?

[ctrueden]

@kephale Not that I know of. But I know next to nothing about XInitThreads. Why is this even necessary in the first place? What impact does it have to run or not run it? I have no idea.

[kephale]

Yeah, all I know is that you get race conditions if you don't run it. sciview is still being haunted by whatever race conditions are happening on Linux, which can't be just XInitThreads...

[skalarproduktraum]

#44 brings this one step closer 👍