TCP/UDP网络通信

#include<winsock2.h>
#include<stdio.h>
#include<time.h>
#include<string.h>
#include<iostream>
using namespace std;
#pragma comment(lib,"ws2_32.lib")
#define SERVER_PORT 8081 
int main()
{
    WSADATA wsa;
    WSAStartup(WINSOCK_VERSION,&wsa);//初始化WS2_32.DLL
    SOCKET serversoc;
    SOCKET clientsoc;
    SOCKADDR_IN serveraddr;
    SOCKADDR_IN clientaddr;

    int client_len = sizeof(clientaddr);
    int server_len = sizeof(serveraddr);
    char *Send_data;
    int Send_len;
    char Recv_buf[64];
    char Send_buf[64];
    int result;
    time_t nowtime;
    //命名协议，IP，端口
    serveraddr.sin_family = AF_INET;
    serveraddr.sin_port = htons(SERVER_PORT);
    serveraddr.sin_addr.s_addr = INADDR_ANY;
    //创建socket
    socket = socket(AF_INET,SOCK_DGRAM,0);
    //绑定socket
    socket=bind(serversoc, (SOCKADDR *)&serveraddr, server_len);
    (result==SOCKET_ERROR)
    {
        ("bind socket failed!\n");
        (serversoc);
        -1;
    }
    printf("Server is running.....\n");
    clientsoc = socket(AF_INET,SOCK_DGRAM,0);
    while(1)
        {   
            //接收数据
            result = recvfrom(serversoc,Recv_buf,64,0,(SOCKADDR *)&clientaddr,&client_len);

            if(result >= 0)
            {
                Recv_buf[result]= 0;
                printf("recieve message:  %s \n",Recv_buf);
                            //发送数据
                            //nowtime=time(0);
                            //Send_data=ctime(&nowtime);
                printf("please input your message: ");
                cin >> Send_buf;
                Send_len=strlen(Send_buf);
                result = sendto(clientsoc,Send_buf,Send_len,0,(SOCKADDR *)&clientaddr,sizeof(clientaddr));
                printf("message has send:  %s \n", Send_buf);
            }
    }
    closesocket(serversoc);
    WSACleanup();
    return 0;
}

#include<winsock2.h>
#include<stdio.h>
#include<string.h>
#include<iostream>
using namespace std;
#pragma comment(lib,"ws2_32.lib")
# define BUFFER_SIZE 1024 //缓冲区大小
# define SERVER_PORT 8081
# define SERVER_IP "127.0.0.1"
int main()
{
    SOCKET sock_Client; //客户端用于通信的Socket
    WSADATA WSAData;//这个结构被用来存储被WSAStartup函数调用后返回的 Windows Sockets数据。它包含Winsock.dll执行的数据。

    char receBuf[BUFFER_SIZE]; //发送数据的缓冲区
    char sendBuf[BUFFER_SIZE]; //接受数据的缓冲区

    //向操作系统说明，我们要用哪个库文件，让该库文件与当前的应用程序绑定，从而就可以调用该版本的socket的各种函数
    //进行相应的socket库绑定
    if (WSAStartup(MAKEWORD(2, 2), &WSAData) != 0)
    {
        printf("init failed!");
        return -1;
    } 
    
    //初始化              (IPV4/v6 ，流式/数据报，UDP/TCP)
    sock_Client = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);//创建客户端用于通信的Socket
    SOCKADDR_IN addr_server; //服务器的地址数据结构
    addr_server.sin_family = AF_INET;
    addr_server.sin_port = htons(SERVER_PORT);//端口号
    addr_server.sin_addr.S_un.S_addr = inet_addr(SERVER_IP); //server IP地址
    SOCKADDR_IN sock;
    int len = sizeof(sock);
    while (true)
    {
        cout << "please input your message:";
        cin >> sendBuf;
        sendto(sock_Client, sendBuf, strlen(sendBuf), 0, (SOCKADDR*)&addr_server, sizeof(SOCKADDR));
        printf("now waiting for reply: \n");
        while(1)
        {
            //接收
            //int last = recv(sock_Client, receBuf, strlen(receBuf), 0); // (调用recv和recvfrom都可以)
            int last = recvfrom(sock_Client, receBuf, 10240, 0, (SOCKADDR*)&sock, &len);
            if (last>0)
            {
                receBuf[last] = '\0'; //给字符数组加一个'\0'，表示结束了。不然输出有乱码
                printf("recieve from server:%s\n", receBuf);
                break;
            }
        }
    }
    closesocket(sock_Client);
    WSACleanup();
    return 0;
}