static void Main(string[] args) { // create a dictionnary string errmsg = ""; KnownHubs = new List <string>(); Console.WriteLine("Waiting for hubs to signal themselves..."); // register the callback: HubDiscovered will be // invoked each time a hub signals its presence YAPI.RegisterHubDiscoveryCallback(HubDiscovered); // wait for 30 seconds, doing nothing. for (int i = 0; i < 30; i++) { YAPI.UpdateDeviceList(ref errmsg); YAPI.Sleep(1000, ref errmsg); } }