Socket: Comment envoyer et recevoir des octets?

//SENDLINE
void Socket::SendLine(std::string s) {
  s += '\n';
  send(s_,s.c_str(),s.length(),0);
}

//RECEIVELINE
std::string Socket::ReceiveLine() {
  std::string ret;
 //Infinite loop  
 while (1) {
    char r;

	//switch(variable)
    switch(recv(s_, &r, 1, 0)) //Descriptor that identifies a connected 
		//socket, a pointer to the buffer to receive incomming data (r adress), 
		//length in bytes of the buffer pointed,a set of flag that influence the 
		//behavior of this function. 
{   
      case 0: //If recv retiurn 0 the connection is close
			  // not connected anymore;
              // ... but last line sent
              // might not end in \n,
              // so return ret anyway.
        return ret;
      case -1://Error managment
        return "";
//      if (errno == EAGAIN) {
//        return ret;
//      } else {
//      // not connected anymore
//      return "";
//      }
    }

//SENDBYTES
void Socket::SendBytes(std::vector< char > p) {
  send(s_,p,p.size(),0);
}


std::vector< char > Socket::ReceiveLine() {
  std::vector< char > ret;
 //Infinite loop  
 while (1) {
    char r;

	//switch(variable)
    switch(recv(s_, &r, 1, 0)) //Descriptor that identifies a connected 
		//socket, a pointer to the buffer to receive incomming data (r adress), 
		//length in bytes of the buffer pointed,a set of flag that influence the 
		//behavior of this function. 
{   
      case 0: //If recv retiurn 0 the connection is close
			  // not connected anymore;
              // ... but last line sent
              // might not end in \n,
              // so return ret anyway.
        return ret;
      case -1://Error managment
        return std::vector< char >NULL;
//      if (errno == EAGAIN) {
//        return ret;
//      } else {
//      // not connected anymore
//      return "";
//      }
    }

std::vector< char > Socket::ReceiveLine() {