gistfile1.cpp

  void HandleRpcs() {
    new CallData(&service_, cq_.get());
    void* tag;
    bool ok;
    while (true) {
      switch (cq_->AsyncNext(&tag, &ok, gpr_inf_past) {
      case TIMEOUT:
        doSomethingElseForALittleWhile();
        continue;
      case SHUTDOWN:
        return;
      case GOT_EVENT:
        GPR_ASSERT(ok);
        static_cast<CallData*>(tag)->Proceed();
        break;
      }
    }
  }