how to change program to broadcast?

[beginner123]

i created a client server program in mfc where the server shows all the ip addresses of the clients in a listbox. the client just clicks a button to connect to the server.
but now i want to change the code to broadcasting but i'm not sure how.

in the client i told it what ip address to connect to but with broadcasting i don't have to do that.

so can someone help me change the code to broadcasting?

server code:

void CSocketTestServerDlg::StartServer()
{
	SOCKADDR_IN serveraddr;
    int portno = 1818;
    memset(&serveraddr,0, sizeof(serveraddr));
    serveraddr.sin_family = AF_INET;
    serveraddr.sin_port = htons(portno);
    serveraddr.sin_addr.s_addr = INADDR_ANY;

    m_serversocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if(m_serversocket == -1)
    {
        AfxMessageBox("Socket Initialiation Error");
    }

    if(bind(m_serversocket, (SOCKADDR*)&serveraddr,sizeof(SOCKADDR_IN)) < 0) 
    {
         AfxMessageBox("ERROR binding in the server socket");
         exit(1);
    }

    if(listen(m_serversocket,0) < 0)
    {
         AfxMessageBox("ERROR listening in the server socket");
         exit(1);
    }	

    SetTimer(0x01, 100, NULL);
}

static void f(void *p)
{
    CSocketTestServerDlg *pDlg = reinterpret_cast<CSocketTestServerDlg*>(p);
    pDlg->ProcessClientRequest();
}

void CSocketTestServerDlg::ProcessClientRequest()
{
    SOCKADDR_IN clientaddr;
    struct hostent *hostentry;
    int len = sizeof(clientaddr);
    SOCKET clientsocket = accept(m_serversocket, (sockaddr*)&clientaddr, &len);
    
    if(len == -1)
    {
        AfxMessageBox("Error accpeting the client socket");
    }
    else
    {
        char *p = inet_ntoa(clientaddr.sin_addr);
        int portno = ntohs(clientaddr.sin_port);
        // int inet_pton(int af, const char *restrict src, void *restrict dst);
 

		CString str(p);
		CListBox listbox;
		listbox.AddString(str);

        CString strRecvData;
	c_MyListBox.AddString(CString(p));

        m_bRefershData = true;
		
        closesocket(clientsocket);
    }
}

client code:

void CSocketTestClientDlg::OnBnClickedOk() //connect button
{
   
    SOCKET s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
    if(s == -1)
    {
        AfxMessageBox("Socket Initialiation Error");
    }
    SOCKADDR_IN serveraddr;
    struct hostent *hostentry;

    
    bool bSent = false;
    std::string server = "10.13.32.132";
    int portno = 1818;
    
    hostentry = gethostbyname(server.c_str());
    char *pipaddr = inet_ntoa (*(struct in_addr *)*hostentry->h_addr_list);

     memset(&serveraddr,0, sizeof(serveraddr));
     serveraddr.sin_family = AF_INET;
     serveraddr.sin_port = htons(portno);
     serveraddr.sin_addr.s_addr = inet_addr(pipaddr);

    //serv_addr.sa_data = htons(portno);

    if (connect(s,(SOCKADDR*)&serveraddr,sizeof(SOCKADDR_IN)) < 0) 
    {
         CString msg = "ERROR connecting to the server: ";
		 msg += _com_error(HRESULT_FROM_WIN32(WSAGetLastError())).ErrorMessage();
		 AfxMessageBox(msg);
		 exit(1);
    }	
    
    UpdateData(TRUE);
    ::closesocket(s);
}

[beginner123]

can someone please help with this?

[MSEBS1967]

Broadcasting with TCP sockets is not possible.
You'll first have to change the communication to UDP sockets:
socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
-> socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);

The socket mechanisms are slightly different, e.g. you'll have no underlying confirmation of received packages.

For sending you may use then INADDR_BROADCAST as target:

targetaddress.sin_addr.S_un.S_addr = INADDR_BROADCAST; 
sendto(udp_targetsocket,(const char*)buffer,msgSize,0,(const sockaddr*)&targetaddress,(int)sizeof(targetaddress));