g_assert(!g->register_time_event);
g->register_time_event = avahi_time_event_queue_add(g->server->time_event_queue, &g->register_time, entry_group_register_time_event_callback, g);
g_assert(!g->register_time_event);
g->register_time_event = avahi_time_event_queue_add(g->server->time_event_queue, &g->register_time, entry_group_register_time_event_callback, g);