Daytime service UDP 클라이언트<윈도우기반>

               #include<stdio.h>

#include<stdlib.h>

#include<string.h>

#include<winsock2.h>

#include<time.h>

 

#pragma comment(lib,"ws2_32.lib")

 

#define BUFSIZE 30

 

void ErrorHandling(char *message);

 

int main(int argc, char **argv)

{

            WSADATA wsaData;

            SOCKET hSocket;

            char message[BUFSIZE];

            int strLen,addrSize,i;

 

            SOCKADDR_IN servAddr;

            SOCKADDR_IN fromAddr;

 

            time_t timer = time(NULL);

            struct tm* t = localtime(&timer);

 

            if(WSAStartup(MAKEWORD(2,2),&wsaData)!=0)

                      ErrorHandling("WSAStartup() error!");

                                     hSocket=socket(PF_INET,SOCK_DGRAM,0);

            if(hSocket ==INVALID_SOCKET)

                      ErrorHandling("socket() error");

 

 

            memset(&servAddr, 0, sizeof(servAddr));

            servAddr.sin_family=AF_INET;

            servAddr.sin_addr.s_addr=inet_addr("127.0.0.1");

            servAddr.sin_port=htons(4000);

 

 

            if(connect(hSocket, (struct sockaddr*)&servAddr, sizeof(servAddr))==SOCKET_ERROR)

                       ErrorHandling("connect() error!");

 

 

 

           while(1)

                            {                  

                     fputs("Daytime 서버에 접속하시겠습니까(y/n) : ", stdout);

                     fgets(message, BUFSIZE, stdin); fflush(stdin);

 

                                                  if(!strcmp(message,"y\n"))

                                                            {

                                                                 sendto(hSocket,message,sizeof(message),0,(SOCKADDR*)&servAddr,sizeof(servAddr));

                            addrSize = sizeof(fromAddr);

                            strLen = recvfrom(hSocket,message,BUFSIZE,0,(SOCKADDR*)&fromAddr,&addrSize);

                            recvfrom(hSocket,(char *)t,sizeof(struct tm),0,(SOCKADDR*)&fromAddr,&addrSize);                 

                              message[strLen]=0;

                            printf("서버로부터 전송된 메시지 : ");

                            printf("%4d년%4d월%4d일%4d시%4d분\n",t->tm_year+1900,t->tm_mon+1,t->tm_mday,t->tm_hour,t->tm_min);

 

                                                            }

 

                     else if (!strcmp(message,"n\n")) break;

 

                     else continue;

 

                                                 }

 

            closesocket(hSocket);

            WSACleanup();

            return 0;

}

 

void ErrorHandling(char *message)

 

{

 

            fputs(message, stderr);

            fputc('\n', stderr);

            exit(1);

 

}