用C語言編寫一個server.c的伺服器端程式，用於接收客戶端的連線，連線成功後，每2秒鐘通過建立的連線向客戶端傳送當前的時間

#include <stdio.h>
#include <stdlib.h>  
#include <string.h>  
#include <unistd.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include <netinet/in.h>  
#include <arpa/inet.h>
#include <sys/socket.h>
#include <time.h>

#define SERV_PORT 8888
#define BACKLOG 20
#define BUF_SIZE 256

int main(int argc, char *argv[])
{
	int ret;
	time_t tt;
	struct tm *ttm;
	char buf[BUF_SIZE];
	pid_t pid;
	int sockfd;
	int clientfd;
	struct sockaddr_in host_addr;
	struct sockaddr_in client_addr;
	int length = sizeof client_addr;
	sockfd = socket(AF_INET,SOCK_STREAM, 0);
	if(sockfd == -1)
	{
		printf("create socket failed.\n");
		return 0;
	}
	bzero(&host_addr, sizeof(host_addr));
	host_addr.sin_family=AF_INET;  
	host_addr.sin_port=htons(SERV_PORT);  
	host_addr.sin_addr.s_addr= INADDR_ANY;
	ret = bind(sockfd, (struct sockaddr *)&host_addr, sizeof host_addr);
	if(ret == -1)
	{
		printf("bind failed.\n");
		return 1;
	}else 
	{
		printf("bind success.\n");
	}	

	ret = listen(sockfd, BACKLOG);
	if(ret == -1)
	{
		printf("listen failed.\n");
		return 1;
	}else
	{
		printf("listen success.\n");
	}

	while(1)
	{
		clientfd = accept(sockfd, (struct sockaddr *)&client_addr, &length);
		if(clientfd == -1)
		{
			printf("accept faild.\n");
			return 1;
		}else {
			printf("accept success.clientfd is %d.\n", clientfd);
		}
		pid = fork();
		if(pid == 0) 
		{
			while(1)
			{
				bzero(buf, sizeof buf);
				tt = time(NULL);
				ttm = localtime(&tt);
				strcpy(buf, asctime(ttm));
				printf("begin send to client\n");
				send(clientfd, buf, strlen(buf), 0);
				sleep(2);
			}
			close(clientfd);
		}else if(pid > 0)
		{
			close(clientfd);
		}

	}

	return 0;
}
 

客戶端用Java來實現

package com.study;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.Socket;

public class Client {
	public static void main(String[] args) throws Exception {
		Socket socket = new Socket("10.180.0.181", 8888);
		StringBuffer sb = new StringBuffer();
		BufferedReader is = new BufferedReader(new InputStreamReader(
				socket.getInputStream()));
		char[] b = new char[1024];
		int len;
		while ((len = is.read(b)) > 0) {
			sb.append(b);
			System.out.println(new String(b, 0, len));
		}
	}
}
 

<pre name="code" class="html"><span style="font-family: Arial, Helvetica, sans-serif; background-color: rgb(255, 255, 255);">客戶端用C語言實現</span>

#include <stdio.h>
#include <stdlib.h>  
#include <string.h>  
#include <unistd.h>  
#include <sys/types.h>  
#include <sys/socket.h>  
#include <netinet/in.h>  
#include <sys/socket.h>
#include <time.h>

#define SERV_PORT 8888
#define BACKLOG 20
#define BUF_SIZE 256

int main(int argc, char *argv[])
{
	int ret;
	char buf[BUF_SIZE];
	int sockfd;						//定義socket描述符
	struct sockaddr_in serv_addr;	//伺服器IP地址和埠資訊
	if(argc != 2)
	{
		printf("命令列輸入有誤.\n");
		return 1;
	}

	//建立套接字
	sockfd = socket(AF_INET, SOCK_STREAM, 0);	//TCP/IP協議,資料流套接字
	if(sockfd == -1)
	{
		printf("呼叫socket函式失敗.\n");
		return 2;
	}

	//建立連線
	bzero(&serv_addr, sizeof serv_addr);
	serv_addr.sin_family = AF_INET;					//TCP/IP協議
	serv_addr.sin_port = htons(SERV_PORT);			//設定埠
	serv_addr.sin_addr.s_addr = INADDR_ANY;		//使用迴環地址127.0.0.1
	inet_aton(argv[1], (struct sockaddr *)&serv_addr.sin_addr.s_addr);
	ret = connect(sockfd, (struct sockaddr *)&serv_addr, sizeof serv_addr);	//繫結套接字
	if(ret == -1) {
		printf("呼叫connect函式失敗.\n");
		return 3;
	}else
	{
		printf("connect success.\n");
	}

	while(1)
	{
		bzero(buf, sizeof buf);
		recv(sockfd, buf, sizeof(buf), 0);
		printf("接收到:%s", buf);
		sleep(1);
	}
	
	return 0;
}
 

執行./client 10.180.0.181

客戶端結果為: