I'm trying to get a global hotkey working in Linux using Mono. I found the signatures of XGrabKey and XUngrabKey, but I can't seem to get them working. Whenever I try to invoke XGrabKey, the application crashes with a SIGSEGV.

This is what I have so far:

using System;
using Gtk;
using System.Runtime.InteropServices;

namespace GTKTest
{
    class MainClass
    {
        const int GrabModeAsync = 1;

        public static void Main(string[] args)
        {
            Application.Init();

            MainWindow win = new MainWindow();
            win.Show();

            // Crashes here
            XGrabKey(
             win.Display.Handle,
             (int)Gdk.Key.A,
             (uint)KeyMasks.ShiftMask,
             win.Handle,
             true,
             GrabModeAsync,
             GrabModeAsync);

            Application.Run();

            XUngrabKey(
             win.Display.Handle,
             (int)Gdk.Key.A,
             (uint)KeyMasks.ShiftMask,
             win.Handle);
        }


        [DllImport("libX11")]
        internal static extern int XGrabKey(
         IntPtr display,
         int keycode,
         uint modifiers,
         IntPtr grab_window,
         bool owner_events,
         int pointer_mode,
         int keyboard_mode);

        [DllImport("libX11")]
        internal static extern int XUngrabKey(
         IntPtr display,
         int keycode,
         uint modifiers,
         IntPtr grab_window);
    }

    public enum KeyMasks
    {
        ShiftMask = (1 << 0),
        LockMask = (1 << 1),
        ControlMask = (1 << 2),
        Mod1Mask = (1 << 3),
        Mod2Mask = (1 << 4),
        Mod3Mask = (1 << 5),
        Mod4Mask = (1 << 6),
        Mod5Mask = (1 << 7)
    }
}

Does anyone have a working example of XGrabKey?

Thanks!