I’m making a chat program with clients and servers using MFC and Winsock. The client socket is being managed by putting it in std::vector. There was a problem with the service when the client socket was accept.

I would like to receive the information of the client that is stored in the socket (vector) and print it out on the ListBox

Is there a way to extract and print out specific information in the vector? Also, I would like to print out the contents of the recv without using a repetitive sentence, what should I do?

It’s the server code

static UINT ServerFunc(LPVOID pVoid)
{
    CServerDlg *dlg = (CServerDlg *)AfxGetApp()->m_pMainWnd;

    CString slniPath;
    slniPath.Format(_T("./NetworkPath.ini"));
    TCHAR ServerPort[MAX_PATH];
    int ServerPort_Num;
    GetPrivateProfileString(_T("ServerInfo"), _T("Port"), _T(""), ServerPort, MAX_PATH, slniPath);
    ServerPort_Num = _ttoi(ServerPort);

    TCHAR ClientCount[MAX_PATH];
    int ClientCount_Num;
    GetPrivateProfileString(_T("ServerInfo"), _T("ClientCount"), _T(""), ClientCount, MAX_PATH, slniPath);
    ClientCount_Num = _ttoi(ClientCount);
    

    WSADATA wsaData;
    int retval = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (retval != 0)
    {
        AfxMessageBox("WSAStartup() Error\n");
        return 0;
    }

    //--SOCKET--
    dlg->server_sock = socket(AF_INET, SOCK_STREAM, 0); 
    if (dlg->server_sock == SOCKET_ERROR) 
    {
        AfxMessageBox("socket() Error\n");
        return 0;
    }
    dlg->server_addr = { 0 };
    dlg->server_addr.sin_family = AF_INET;
    dlg->server_addr.sin_port = htons(ServerPort_Num);
    dlg->server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    //bind
    retval = bind(dlg->server_sock, (SOCKADDR*)&dlg->server_addr, sizeof(SOCKADDR));

    if (retval == SOCKET_ERROR) 
    {
        AfxMessageBox("bind() Error\n");
        return 0;
    }
    listen(dlg->server_sock, ClientCount_Num); 

    AfxMessageBox("Server Start\n");

    //accept 
    while (1)
    {
#if 1
        dlg->client_addr = { 0 };
        dlg->client_addr.sin_family = AF_INET;
        dlg->client_addr.sin_port = htons(ServerPort_Num);
        dlg->client_addr.sin_addr.s_addr = htonl(INADDR_ANY);

        int size = sizeof(SOCKADDR_IN);
#endif
        dlg->client_sock = accept(dlg->server_sock, (SOCKADDR*)&dlg->client_addr, &size);
        if (dlg->client_sock == SOCKET_ERROR) 
        {
            AfxMessageBox("accept() Error");
            continue;
        }
        client_list.push_back(dlg->client_sock);

        CString ConnectInfo_str;
        CString ConnectInfo_str2;
        
        ConnectInfo_str.Format("IP : %s\n", inet_ntoa(dlg->client_addr.sin_addr)); 
        ConnectInfo_str2.Format("IP : %s Join \n", inet_ntoa(dlg->client_addr.sin_addr));
        dlg->m_ListClient.AddString(ConnectInfo_str);
        dlg->m_ListChat.AddString(ConnectInfo_str2);

        dlg->pThreadTcpServer_Data = AfxBeginThread(ServerRecvSendFunc, (void *)dlg->client_sock);
    }
    closesocket(dlg->server_sock);
    WSACleanup;

    return 0;

}

It’s the service code

#if 1
#define BUFSIZE 128
static UINT ServerRecvSendFunc(void *p)
{
    CServerDlg *dlg = (CServerDlg *)AfxGetApp()->m_pMainWnd;
    SOCKET socket = (SOCKET)p;


    char readbuffer[BUFSIZE + 1];
    BYTE readbuffer__[BUFSIZE + 1];
    int recvsize;

    BYTE SendBuffer_TEST[BUFSIZE + 1];

    while (1)
    {
        recvsize = recv(socket, readbuffer, BUFSIZE, 0);

        if (recvsize <= 0)
        {
            break;
        }
        readbuffer[recvsize] = '\0';

        CString strTemp;
        CString strMsg;

        char temp[60];
        memset(readbuffer__, 0x00, sizeof(readbuffer__));
        memcpy(&readbuffer__, &readbuffer[0], BUFSIZE);
        for (int i = 0; i < recvsize; i++)
        {
            strTemp.Format(_T("%c"),readbuffer[i]);
            strMsg += strTemp;
        }
        dlg->m_ListChat.AddString(strMsg);
        strMsg = "";
        strTemp = "";
#if 1
        //log
#endif
        //log
#if 1
        for (int i = 0; i < client_list.size(); i++)
        {
            if (client_list[i] == socket)
            {
                int sendsize = send(client_list[i], readbuffer, strlen(readbuffer), 0);
            }
        }
#endif
    }
#if 1
    
    CString DisConnectInfo_str;
    CString DisConnectInfo_str2;
    
    
    std::vector<SOCKET>::iterator iter = client_list.begin();
    for (int i = 0; i < client_list.size(); i++)
    {
        if (client_list[i] == socket) 
        {
            client_list.erase(iter); 
            break;
        }
        iter++;
    }
#endif  
    if (socket == NULL)
    {
    }
    closesocket(socket);
}
#endif