【tcp-ip学习总结】基础UDP实现的简单通信功能小程序

环境：VS2013

#include<Winsock2.h>#include<stdio.h>#include<stdlib.h>#pragma comment(lib,"ws2_32.lib")#define DEFAULT_PORT 8888#define BUFFER_LENGTH 1024void main(){    int iPort = DEFAULT_PORT;    WSADATA wsaData;//协议栈    SOCKET sSocket;//服务端的socket    int iLen;//客户端地址长度    int iSend;//发送数据的长度    int iRecv;//接受数据的缓冲区长度    char sendBuf[] = "Hello! I am server";//服务端要发送的字符串    char recvBuf[BUFFER_LENGTH];//服务器端接受数据的缓冲区    struct sockaddr_in ser, cli; //本地地址和客户地址    printf("-----------------\n");    printf("Server waiting\n");    printf("-----------------\n");    //加载协议栈    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)    {        printf("Failed to load Winsock.\n");        return;    }    //创建服务器端的socket套接口    sSocket = socket(AF_INET, SOCK_DGRAM, 0);    if (sSocket == INVALID_SOCKET)    {        printf("socket(Failed:%d\n)", WSAGetLastError);        return;    }    //初始化服务器端的地址与端口号    ser.sin_family = AF_INET;    ser.sin_port = htons(8888);//服务器端监听的端口号    ser.sin_addr.s_addr = htonl(INADDR_ANY);//服务端的端口地址    //将服务器端socket和服务器的端ip地址和端口号绑定，    if (bind(sSocket, (LPSOCKADDR)&ser, sizeof(ser)) == SOCKET_ERROR)    {        printf("bind() Failed:%d\n", WSAGetLastError());        return;    }    iLen = sizeof(cli);    memset(recvBuf, 0, sizeof(recvBuf));//将接收缓冲区内容全部初始化为0    while (1)    {    //从服务器端套接口中接收数据，并把客户端的地址情况保存到cli上面        iRecv = recvfrom(sSocket, recvBuf, BUFFER_LENGTH, 0,(SOCKADDR*)&cli,&iLen);        if (iRecv == SOCKET_ERROR)        {            printf("recvfrom()Faild;%d\n", WSAGetLastError());            break;        }         else if (iRecv == 0)        {            break;        }        else        {            printf("recvfrom():%s\n", recvBuf);            printf("accepted client ip[%s], port[%d]\n", inet_ntoa(cli.sin_addr), ntohs(cli.sin_port));        }    //向客户端发送数据        iSend = sendto(sSocket, sendBuf, sizeof(sendBuf), 0, (SOCKADDR*)&cli, sizeof(cli));        if (iSend == SOCKET_ERROR)        {            printf("sendto() Faild:%d\n", WSAGetLastError());            printf("----------\n");            break;        }        else if (iSend == 0)            break;        else        {            printf("sendto() succeeded\n");            printf("-=---------\n");        }    }    closesocket(sSocket);//关闭套接口    WSACleanup();//清空协议栈}

client.c

#include<Winsock2.h>#include<stdio.h>#pragma comment(lib,"ws2_32.lib")void main(){    WSADATA wsaData;//协议栈    SOCKET sClient;//客户端套接口    struct sockaddr_in ser;//客户端地址    int iPort = 8888;    int iLen;//客户端地址长度    int iSend;    int iRecv;    char sendBuf[1024];//发送数据缓冲区    char recvBuf[1024];//接收数据缓冲区    memset(recvBuf, 0, sizeof(recvBuf));//把接收数据缓冲区初始化为0    //加载协议栈    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)    {        printf("Failed to load Winsock\n");        return;    }    //初始化客户端地址情况    ser.sin_family =  AF_INET;    ser.sin_port = htons(8888);    ser.sin_addr.s_addr = inet_addr("127.0.0.1");    //创建客户端套接口    sClient = socket(AF_INET, SOCK_DGRAM, 0);    if (sClient == INVALID_SOCKET)    {        printf("socket() Faild %d\n", WSAGetLastError());        return;    }    iLen = sizeof(ser);    while (1) {        printf_s("请输入要发送的消息:");        gets_s(sendBuf, 1024);        //开始发送数据        iSend = sendto(sClient, sendBuf, sizeof(sendBuf), 0, (struct sockaddr*)&ser, iLen);        if (iSend == SOCKET_ERROR)        {            printf("sendto()faild %d", WSAGetLastError());            return;        }        else if (iSend = 0)        {            return;        }        else {            printf("sendto() succeeded\n");        }        //接收数据        iRecv = recvfrom(sClient, recvBuf, sizeof(recvBuf), 0, (struct sockaddr*)&ser, &iLen);        if (iRecv == SOCKET_ERROR)        {            printf("recvfrom() faild %d\n", WSAGetLastError());            return;        }        else if (iRecv == 0)            return;        else {            printf("recvfrom() %s", recvBuf);            printf("-----------------\n");        }    }    closesocket(sClient);//关闭套接口    WSACleanup();//清空协议栈}