int setopt(int level, int optname, const void* optval, socklen_t optlen);
virtual int close();
virtual std::shared_ptr<message_t> read_message() = 0;
int setopt(int level, int optname, const void* optval, socklen_t optlen);
virtual int close();
virtual std::shared_ptr<message_t> read_message() = 0;