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c++socketsnetwork-programmingtcpwinsock

C++ winsock TCP listening


I have a software that decodes ADS-B messages (from planes) and sends results in hexadecimal to a port (47806).

I would like to listen to this port to show that data, so I wrote this :

WSADATA WSAData;
WSAStartup(MAKEWORD(2, 0), & WSAData);

SOCKET sock;
SOCKADDR_IN socket_in;
socket_in.sin_addr.s_addr = htonl(INADDR_ANY);
socket_in.sin_family = AF_INET;
socket_in.sin_port = htons(47806);
sock = socket(AF_INET, SOCK_STREAM, 0);
bind(sock, (SOCKADDR*)& socket_in, sizeof(socket_in));

listen(sock, 0);
int valid = 0;
while (TRUE) {
    int size_socket_in = sizeof(socket_in);
    valid = accept(sock, (SOCKADDR*)& socket_in, & size_socket_in);

    if (valid != INVALID_SOCKET) {
        std::cout << "OK";
    }
}

This code should display "OK" each time a message is received, but it doesn't. I can read data with a Telnet software, like PuTTY : PuTTY telnet on port 47806

I don't understand why my code doesn't work.


Solution

  • Here's the right code :

    WSADATA WSAData;
    WSAStartup(MAKEWORD(2, 0), & WSAData);
    
    SOCKET sock;
    SOCKADDR_IN socket_in;
    InetPton(AF_INET, "127.0.0.1", & socket_in.sin_addr.s_addr);
    socket_in.sin_family = AF_INET;
    socket_in.sin_port = htons(47806);
    sock = socket(AF_INET, SOCK_STREAM, 0);
    connect(sock, (SOCKADDR*)& socket_in, sizeof(socket_in));
    
    int valid = 0;
    char buffer[512] = "";
    while (TRUE) {
        valid = recv(sock, buffer, sizeof(buffer), 0);
    
        if (valid != INVALID_SOCKET) {
            std::cout << buffer;
        }
    }
    

    My program is a client and not a server. So I have to define an IP adress with InetPton, connect to the server with connect and receive the messages with recv.

    Thank you @Hasturkun and @RustyX for help and explanations.