如题。我想实现Client端和Server端同时具有收发的功能，于是我想到了双线程。
目前正在调试Client端。
如下：
WSAStartup
ZeroMemory
getaddrinfo
freeaddrinfo
_beginthreadex
在创建的新的线程里面，调用send函数。
发现发送不过去。
而如果将_beginthreadex开启的新的线程里面的函数，放在main函数中，则可以正常进行。
很困惑这个问题，是不是在新的线程里面要重新进行初始化——连接   等操作？
代码如下，为了方便调试，把接收的注释掉了。

#define WIN32_LEAN_AND_MEAN
#define _CRT_SECURE_NO_WARNINGS

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include <process.h>


// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")


#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "8888"


unsigned int __stdcall Send(void* ConnectSocket)
{
    char input[DEFAULT_BUFLEN];
    gets(input);
    printf("%s", input);
    while (*input != EOF)
    {
        send((int)ConnectSocket, input, (int)strlen(input), 0);
    }
    closesocket((int)ConnectSocket);
    WSACleanup();
    return 1;

    int iResult;
    iResult = shutdown((int)ConnectSocket, SD_SEND);
    if (iResult == SOCKET_ERROR) {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket((int)ConnectSocket);
        WSACleanup();
        return 1;
    }
}



int __cdecl main(int argc, char **argv)
{
    WSADATA wsaData;
    SOCKET ConnectSocket = INVALID_SOCKET;                    //~0==-1,因为Socket 类型被定义为unsigned
    //printf("%d", ~0);                        //-1
    struct addrinfo *result = NULL,
        *ptr = NULL,
        hints;
    char sendbuf[DEFAULT_BUFLEN];                    //发送的文字
    char recvbuf[DEFAULT_BUFLEN];
    int iResult;
    int recvbuflen = DEFAULT_BUFLEN;

    // Validate the parameters
    if (argc != 2) {
        printf("usage: %s server-name\n", argv[0]);
        return 1;
    }

    // Initialize Winsock
    iResult = WSAStartup(MAKEWORD(2, 2), &wsaData);
    if (iResult != 0) {
        printf("WSAStartup failed with error: %d\n", iResult);
        return 1;
    }

    ZeroMemory(&hints, sizeof(hints));
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;

    // Resolve the server address and port
    iResult = getaddrinfo(argv[1], DEFAULT_PORT, &hints, &result);
    if (iResult != 0) {
        printf("getaddrinfo failed with error: %d\n", iResult);
        WSACleanup();
        return 1;
    }

    // Attempt to connect to an address until one succeeds
    for (ptr = result; ptr != NULL; ptr = ptr->ai_next) {

        // Create a SOCKET for connecting to server
        ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype,ptr->ai_protocol);
        if (ConnectSocket == INVALID_SOCKET) {
            printf("socket failed with error: %ld\n", WSAGetLastError());
            WSACleanup();
            return 1;
        }

        // Connect to server.
        iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
        printf("Waiting...\n");
        while (iResult == SOCKET_ERROR) 
        {
            iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
        }
        printf("Connect!\n");
        break;
    }

    freeaddrinfo(result);


    // Send an initial buffer
    _beginthreadex(NULL, 0, Send, NULL, 0, NULL);                  //创建一个线程

    //do {

    //    iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
    //    if (iResult > 0){
    //        printf("Bytes received: %d\n", iResult);
    //        recvbuf[iResult] = '\0';
    //        printf("Receive:\n%s\n", recvbuf);
    //    }
    //        

    //} while (true);

    // cleanup
    /*closesocket(ConnectSocket);
    WSACleanup();*/
    while (true)
    {
        ;
    }
    system("pause");
    return 0;
}

最后，为了防止主函数结束，我用了死循环。
我的联系方式：littlesevenmo@vip.
不胜感激。