text: #ifndef CROW_PROTOCOL_H
  #define CROW_PROTOCOL_H
  
  #include <crow/packet.h>
  
  namespace crow
  {
      class protocol
      {
        public:
          virtual void incoming(crow::packet *pack) = 0;
          virtual void undelivered(crow::packet *pack) = 0;
      };
  }
  
  #endif