用于Windows的套接字程序

Question

我正在为Windows编写套接字程序并尝试在客户端和服务器之间创建通信。我正在使用select（）api。但它是错误的错误：从不成功中恢复任何人都可以帮助我吗？

while(1)
{
    //memset(buffer, 0, sizeof(buffer));

    //blocks only for specified time
    status = select(0, &ReadSet, NULL, NULL, &tv);

    if (status == -1) 
    {
        extern int errno;
        cerr << "ERROR: Select unsuccessful: Error" << WSAGetLastError() << endl;
        cout << "ERRNO: " << _errno << endl;
    } 
    else if (status == 0) 
    {
        cout<<"Timeout occurred!  No data after 500ms" << endl; 
    } 
    else
    {
        if (FD_ISSET(clientSocket, &ReadSet)) 
        {
            // Receieve74.    
            numrcv = recv(clientSocket, buffer, MAXBUFLEN, NO_FLAGS_SET);  
            if (numrcv == SOCKET_ERROR)
            {
               cerr << "ERROR: recvfrom unsuccessful" << endl;
            }
            // Print out receieved socket data92.   
            cout << "Message rcvd from client" << buffer<< endl;
        }
    }