internal Subscription AddSubscription(string channel, int streamId) { VerifyActive(); long correlationId = _driverProxy.AddSubscription(channel, streamId); Subscription subscription = new Subscription(this, channel, streamId, correlationId, _ctx.AvailableImageHandler(), _ctx.unavailableImageHandler()); _activeSubscriptions.Add(subscription); AwaitResponse(correlationId, channel); return(subscription); }