Linux X11 - Global Keyboard Hook

Question

Is it possible (or how) to create a mechanism (in Linux X11, C++) that works like a global hook in windows (SetWindowsHookEx())?

I would like to be able to catch the key

Answer 1

no idea if this helps, but I just found this in some code:

    void XFakeKeypress(Display *display, int keysym)
    { 
       XKeyEvent event;                     
       Window current_focus_window;         
       int current_focus_revert;

       XGetInputFocus(/* display = */ display, /* focus_return = */ 
          ¤t_focus_window, /* revert_to_return = */ ¤t_focus_revert);

       event.type = /* (const) */ KeyPress;
       event.display = display;
       event.window = current_focus_window;
       event.root = DefaultRootWindow(/* display = */ display);
       event.subwindow = /* (const) */ None;
       event.time = 1000 * time(/* tloc = */ NULL);
       event.x = 0;
       event.y = 0;
       event.x_root = 0;
       event.y_root = 0;
       event.state = /* (const) */ ShiftMask;   
       event.keycode = XKeysymToKeycode(/* display = */ display, 
          /* keysym = */ keysym);
       event.same_screen = /* (const) */ True;  

       XSendEvent(/* display = */ display, /* w = (const) */ InputFocus,
          /* propagate = (const) */ True, /* event_mask = (const) */ 
          KeyPressMask, /* event_send = */ (XEvent *)(&event));

       event.type = /* (const) */ KeyRelease;   
       event.time = 1000 * time(/* tloc = */ NULL);

       XSendEvent(/* display = */ display, /* w = (const) */ InputFocus,
          /* propagate = (const) */ True, /* event_mask = (const) */ 
          KeyReleaseMask, /* event_send = */ (XEvent *)(&event));
    }