#include 
#include 
#include 
#include 
using namespace std;    #define PORT 8888
int main()
{
        WSADATA wsaData;
    int Ret = WSAStartup(MAKEWORD(2,2),&wsaData);
        printf("Client........!\n");
    if(Ret != 0)
    {
                printf("winsock.\n");
                WSACleanup();
    }
    else{
                
        //        printf("winsock\n");
        }
    
    std::string strIP;
        std::cout << "輸入IP: " << std::flush;
    std::cin >> strIP;
    
        SOCKET socketc=::socket(AF_INET,SOCK_DGRAM,IPPROTO_IP);
        sockaddr_in addr;
        addr.sin_addr.S_un.S_addr = inet_addr(strIP.c_str());
        //addr.sin_addr.S_un.S_addr=inet_addr(IP);
        
        addr.sin_family=AF_INET;
        addr.sin_port=ntohs(PORT);
        
        if(socketc==INVALID_SOCKET)
        {
                printf("socket Error!");
        }            int len=sizeof(sockaddr);
                    while (1)//client
        {
                char buf[200]="\0";
                char rbuf[300]="\0";
            printf("\n:");
                scanf("%s",&buf);
                sendto(socketc,buf,strlen(buf) 1,0,(SOCKADDR*)&addr,len);//.....
        
                recvfrom(socketc,rbuf,sizeof(rbuf),0,(SOCKADDR*)&addr,&len);
                if(strcmp(rbuf,"exit")==0)
                {
                        break;
                }
                printf("%s",rbuf);
                
        }
        
        closesocket(socketc);
        WSACleanup();
        printf("end\n");
        return 0;
}    

#include  
#include 
#include 
using namespace std;    #define PORT 8888
int main() //server
{
        WSADATA wsaData;    int Ret = WSAStartup(MAKEWORD(2,2),&wsaData);
        printf("Server.........!\n");    if(Ret != 0)    {
                printf("winsock.\n");
                WSACleanup();    }    else{
                
        //        printf("winsock\n");
        }
        
        if ( LOBYTE( wsaData.wVersion ) != 2 ||        HIBYTE( wsaData.wVersion ) != 2 )
        {
                WSACleanup( );
                return 1; 
        }            SOCKET socket=::socket(AF_INET,SOCK_DGRAM,IPPROTO_IP);
        sockaddr_in addr;
        addr.sin_addr.S_un.S_addr=INADDR_ANY;
        addr.sin_family=AF_INET;
        addr.sin_port=ntohs(PORT);
        
        
        
        if(socket==INVALID_SOCKET)
        {
                printf("socket Error!");
        }
        int rs=        bind(socket,(sockaddr*)&addr,sizeof(addr));
        
        if (rs!=0)
        {
                printf("bind failed!");
                return 1;
        }
        char buf[200]="\0";
        char temp[200]="\0";
        sockaddr_in addrcl;
        int len=sizeof(sockaddr);
        
        while(1){
                
                recvfrom(socket,buf,sizeof(buf),0,(sockaddr*)&addrcl,&len);
                
                sprintf(temp,"%s:%s",inet_ntoa(addrcl.sin_addr),buf);        sendto(socket,temp,strlen(temp) 1,0,(sockaddr*)&addrcl,sizeof(addr));
                if(strcmp(buf,"srvexit")==0)
                {
                        break;
                }
                printf("%s",buf);
                printf("\n");
        }
        closesocket(socket);
        
        WSACleanup();
        printf("exit\n");
        return 0;
}