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Listening on a Socket

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After the socket is bound to an IP address and port on the system, the server must then listen on that IP address and port for incoming connection requests.

To listen on a socket

Call the listen function, passing as parameters the created socket and a value for the backlog, maximum length of the queue of pending connections to accept. In this example, the backlog parameter was set to SOMAXCONN. This value is a special constant that instructs the Winsock provider for this socket to allow a maximum reasonable number of pending connections in the queue. Check the return value for general errors.

if ( listen( ListenSocket, SOMAXCONN ) == SOCKET_ERROR ) {
    printf( "Listen failed with error: %ld\n", WSAGetLastError() );
    closesocket(ListenSocket);
    WSACleanup();
    return 1;
}

Next Step: Accepting a Connection

Getting Started With Winsock

Winsock Server Application

Binding a Socket