攻略一：听(2) - 操练

拿回一个很老的东西看，这个winsock header不行，下面也只是演示用的。改完再说。

#include <stdio.h>
#include <winsock2.h>

#ifndef __cplusplus
typedef struct sockaddr_in sockaddr_in;
#endif /* __cplusplus */

int main()
{
    WORD wVersionRequested;
    WSADATA wsaData;
    int wsaerr;

    // Using MAKEWORD macro, Winsock version request 2.2

    wVersionRequested = MAKEWORD(2, 2);
    wsaerr = WSAStartup(wVersionRequested, &wsaData);

    if (wsaerr != 0)
    {
        /* Tell the user that we could not find a usable */
        /* WinSock DLL.*/
        printf("The Winsock dll not found!\n");
        return 0;
    }
    else
    {
        printf("The Winsock dll found!\n");
        printf("The status: %s.\n", wsaData.szSystemStatus);
    }

    if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2 )
    {
        /* Tell the user that we could not find a usable */
        /* WinSock DLL.*/
        printf("The dll do not support the Winsock version %u.%u!\n",
                    LOBYTE(wsaData.wVersion),HIBYTE(wsaData.wVersion));
        
        /* Cleanup WSA after use                         */
        WSACleanup();
        return 0; 
    }
    else
    {
        printf("The dll supports the Winsock version %u.%u!\n",
                    LOBYTE(wsaData.wVersion),HIBYTE(wsaData.wVersion));
        printf("The highest version this dll can support: %u.%u\n",
                    LOBYTE(wsaData.wHighVersion), HIBYTE(wsaData.wHighVersion));
    }
    /* The next task... */
    //////////Create a socket////////////////////////

    //Create a SOCKET object called m_socket.
    
    SOCKET m_socket;
    
    // Call the socket function and return its value to the m_socket variable.
    // For this application, use the Internet address family, streaming sockets,
    // and the TCP/IP protocol.
    // using AF_INET family, TCP socket type and protocol of the AF_INET - IPv4
    
    m_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);

    // Check for errors to ensure that the socket is a valid socket.
    if (m_socket == INVALID_SOCKET)
    {
        printf("Error at socket(): %ld\n", WSAGetLastError());
        WSACleanup();
        return 0;
    }
    else
    {
        printf("socket() is OK!\n");
    }
    
    ////////////////bind()//////////////////////////////
    // Create a sockaddr_in object and set its values.
    
    sockaddr_in service;
    
    // AF_INET is the Internet address family.
    service.sin_family = AF_INET;
    
    // "127.0.0.1" is the local IP address to which the socket will be bound.
    service.sin_addr.s_addr = inet_addr("127.0.0.1");
    
    // 55555 is the port number to which the socket will be bound.
    service.sin_port = htons(55555);
    
    // Call the bind function, passing the created socket and the sockaddr_in
    // structure as parameters.
    // Check for general errors.

    if (bind(m_socket, (SOCKADDR*)&service, sizeof(service)) == SOCKET_ERROR)
    {
        printf("bind() failed: %ld.\n", WSAGetLastError());
        closesocket(m_socket);
        return 0;
    }
    else
    {
       printf("bind() is OK!\n");
    }

    return 0;
}