#include <gtk/gtk.h>

int
main (int argc, char **argv)
{
  const char *display_name;
  GdkDisplay *display;
  GtkWidget *win, *but;
  gboolean has_display;

  g_log_set_always_fatal (G_LOG_LEVEL_WARNING | G_LOG_LEVEL_CRITICAL);

  gdk_set_allowed_backends ("x11");
  display_name = g_getenv ("DISPLAY");
  g_unsetenv ("DISPLAY");
  has_display = gtk_init_check ();
  g_assert (!has_display);

  display = gdk_display_open (display_name);

  if (!display)
    return 0;

  gdk_display_manager_set_default_display (gdk_display_manager_get (), display);

  win = gtk_window_new ();

  but = gtk_button_new_with_label ("Try to Exit");
  g_signal_connect_swapped (but, "clicked",
                            G_CALLBACK (gtk_window_destroy), win);
  gtk_window_set_child (GTK_WINDOW (win), but);

  gtk_widget_show (win);

  gtk_test_widget_wait_for_draw (win);

  gdk_display_close (display);

  return 0;
}