class PriceObserver : public ttsdk::IPriceEventHandler
{
  public:
        PriceObserver() {}

      virtual void OnPriceUpdate(const uint64_t subId, 
              const ttsdk::InstrumentPtr& instrument, const ttsdk::PriceSnap& snap)
      {
              std::cout << “Price snapshot received.” << std::endl;
      }

      virtual void OnError(const uint64_t subId, const ttsdk::InstrumentPtr& instrument, 
              const ttsdk::SubscriptionError code, const char* error)
      {
              std::cout << "Error [" << error  << "] occurred for instrument:" 
                      << instrument->GetAlias() << " subId=" << subId 
                      << " code=" << (int)code << std::endl;
      }

      virtual void OnDisconnect(const uint64_t subId, 
              const ttsdk::InstrumentPtr& instrument, const ttsdk::PriceEventType type)
      {
              std::cout << "Prices disconnected for subscription for instrument:" 
                      << instrument->GetAlias() << " subid=" << subId << std::endl;
      }

      virtual void OnUnsubscribed(const uint64_t subId) 
      {
              std::cout << "Price observer for subId=" << subId 
                      << " has been successfully unsubscribed. " << std::endl;
      }        
};

void foo()
{
        // …

        PriceObserver prcObserver;

        ttsdk::Instrument::ResponseCode respCode;
        ttsdk::MarketId market = ttsdk::MarketId::CME;
        std::string product = “GE”;
        ttsdk::ProductType productType = ttsdk::ProductType::Future;
        std::string alias = "GE Sep28";
        ttsdk::InstrumentPtr instrument = ttsdk::GetInstrument(market, product.c_str(),
                  productType, alias.c_str(), respCode);
        if (!instrument)
        {
          std::cout << "Unable to find instrument with alias = “ << alias << std::endl;
        }
        else
        {
          uint64_t subId = 0;
          subId = ttsdk::SubscribePrices(instrument, 10, true, true, false, &prcObserver);
          std::cout << "Subscription id=" << subId << std::endl; 
        }

          // ...
}