client.c

linux环境下udp协议的客户端代码,向服务器端发送请求,显示服务器回应请求的时间

#include<stdio.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<arpa/inet.h>
#include<sys/fcntl.h>
#include<netdb.h>
#include<unistd.h>
#include<stdlib.h>
#include<string.h>
#include <time.h>
#define MAXLINE 128
int main(int argc,char **argv)
{
	//struct sockaddr_in local;
	struct sockaddr_in server;
	int clientSocket;
	char *Time;
	char ReceiveTime[128];
	int port=9257;
	int addr_len;
	time_t t=time(NULL);
	//strftime(Time,sizeof(Time),"%Y/%m/%d %X %A %z", localtime(&t));
	Time = ctime(&t);
	printf("%s\n",Time); 
	if((clientSocket=socket(AF_INET,SOCK_DGRAM,0))<0){
		perror("socket wrong");
		exit(EXIT_FAILURE);
	}
	memset((char*)&server,0,sizeof(server));
	server.sin_family=AF_INET;
	server.sin_port=htons((u_short)port);
	server.sin_addr.s_addr=inet_addr(argv[1]);
	addr_len=sizeof(server);
	//bind(clientSocket,(struct sockaddr *)&local,sizeof(local));
	if(sendto(clientSocket,Time,strlen(Time)+1,0,(struct sockaddr *)&server,addr_len)==-1){
		perror("send errror");
		exit(EXIT_FAILURE);
	}//向服务器提出请求
	if(recvfrom(clientSocket,ReceiveTime,sizeof(ReceiveTime),0,(struct sockaddr*)&server,&addr_len)==-1){
		perror("no receive");
		exit(EXIT_FAILURE);
	}//接受服务器的返回时间
	printf("FROM SERVER:%s\n",ReceiveTime);
	close(clientSocket);  
return 0;
     
}