Capturing global key press events

I'd like to capture global key press events to enable a "Global Shortcuts" feature in my application.

I've looked at a few other projects that have such capabilities and they all seem to hook straight into xlib. Is there a more GTK way of doing it?

At the moment I'm using,
XKeysymToKeycode($DISPLAY,XStringToKeysym("some key in here"));

And then passing the resulting key code to XGrabKey,

Then I call XSync($DISPLAY,0); I dont know why, but if I dont, gtk segfaults. I then wait for events with XNextEvent($DISPLAY,&event); inside a pthread and when an event comes by, i call a signal callback surrounded with gdk_threads_enter and _leave.

Now all this worked nicely for a while, but somehow I've managed to break it :(

It doesnt seem to pick up the events from the keys I passed to XGrabKeys anymore. If I switch to AnyModifier, it picks things up, but obviously the keyboard becomes unusable for other applications then.

I believe XGrabKeys will alert me with a BadAccess error if i try to use a key that is already being grabbed by another x client, but I dont know how well this mechanism works.

Mod4Mask seems to refer to the Super Key, aka, "Windows Key". So in my example I have modifiers Shift+Super and keycode "key".

When it worked, I had Shift+Super+{z,x,c,v,b} setup. Now nothing works and for the best of me, I can't seem to understand what I've changed.

A little background information: My app is heavily threaded, there are about 12+ threads at any given time. They are all created with pthread_create, and use gdk_threads_enter/leave before touching anything gdk/gtk/glib related.

In main() I call g_thread_init( NULL ); and gdk_threads_init(); before gtk_init(argc,argv);

I've read in some places one should surround gtk_main() with gdk_threads_enter/leave, but this absolutely doesnt make any sense to me. If I try to do that, the app locks in gtk_main and doesnt startup.

My assumption is that gdk_threads_enter() "acts" like sem_wait() and gdk_threads_leave() acts like sem_post(), where gdk_threads_init() sets the value of the semaphore to 1.

With this assumption I've used gdk_threads_enter/leave throughout my app and it definitely works.

I'm guessing there is some sort of conflict between the key-press-event for the top level GtkWindow and my xlib key grabbing, but I don't know how to debug the situation further. Any ideas whats going on?


PS: GTK docs are much better than X11 docs :)

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