网络编程

代码：

/*************************************************************************************
 *
 *  file name:  1.c
 *  author   : 	[email protected]
 *  date     :  2024/06/04
 *  function : 	多播通信
 *  note	 ：  none
 *  CopyRight (c)   2024    [email protected]   All Right Reserved
 *
 ************************************************************************************/

#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/udp.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <sys/types.h>       

int udp_socket;
char w_buf[52]={0};
// 运行客户端可执行文件   ./xxx  服务器端口  服务器地址
 /**
  * @name:		sendm
  * @brief  	向目标主机发送消息
  * @param  	
  				@void *arg
  * @retval 	void *
  * @date 		2024/06/04
  * @note   	none
  */
void *sendm(void *arg)
{	
	//2.向目标主机发送消息,需要设置目标端口和目标地址
	char buf[128];

	struct sockaddr_in  dest_addr;
	dest_addr.sin_family 		= AF_INET; 						//协议族，是固定的
	dest_addr.sin_port   		= htons(60000);			//服务器端口，必须转换为网络字节序
	dest_addr.sin_addr.s_addr   = inet_addr("226.66.66.66");			//服务器地址 "192.168.64.xxx"  
	
	while(1)
	{
		scanf("%s",buf);
		sendto(udp_socket,buf,strlen(buf),0, (struct sockaddr *)&dest_addr, sizeof(dest_addr));
	}
	return 0;
}


 /**
  * @name:		gettime
  * @brief  	获取系统时间
  * @param  	
  				@void *arg
  * @retval 	void *
  * @date 		2024/06/04
  * @note   	none
  */
void *gettime(void *arg)
{
	int sec,min,hour,day,week,mon,year;
	// while(1)
	// {
	//利用循环获取系统时间并将它存入变量
		time_t time_sum = time(NULL);
		struct tm *CurTime = localtime(&time_sum);
		sec  = CurTime->tm_sec;
		min  = CurTime->tm_min ;
		hour = CurTime->tm_hour ;
		day  = CurTime->tm_mday ;
		week = CurTime->tm_wday ;
		mon  = CurTime-> tm_mon +1;
		year = CurTime-> tm_year +1900;
	//将变量里的整数用spritf函数全部转换成字符串
	sprintf(w_buf,"%d年%d月%d日,星期%d %d:%d:%d",year,mon,day,week,hour,min,sec);

}
 /**
  * @name:		recvm
  * @brief  	向目标主机发送消息
  * @param  	
  				@void *arg
  * @retval 	void *
  * @date 		2024/06/04
  * @note   	none
  */
void *recvm(void *arg)
{
	//2.向目标主机发送消息,需要设置目标端口和目标地址
	//char buf[128];

	struct sockaddr_in  host_addr;
	host_addr.sin_family 		= AF_INET; 						//协议族，是固定的
	host_addr.sin_port   		= htons(60000);			//服务器端口，必须转换为网络字节序
	host_addr.sin_addr.s_addr   = htonl(INADDR_ANY);
    struct ip_mreqn ip_m;
    ip_m.imr_multiaddr.s_addr= inet_addr("226.66.66.66");
    ip_m.imr_address.s_addr= inet_addr("192.168.64.100");  
    ip_m.imr_ifindex= 0;  
    setsockopt(udp_socket,IPPROTO_IP,IP_ADD_MEMBERSHIP,&ip_m, sizeof(ip_m));

	bind(udp_socket,(struct sockaddr *)&host_addr, sizeof(host_addr));

	//3.发送客户端的上线时间
	
	//3.调用recvfrom等待接收数据，并且接收客户端的网络信息
	char buf[256] = {0};
	struct sockaddr_in  client;
	socklen_t client_len = sizeof(client);
    int flag =1;
    setsockopt(udp_socket,SOL_SOCKET,SO_BROADCAST,&flag,  sizeof(ip_m));
    
	while(1)
	{
		recvfrom(udp_socket,buf,sizeof(buf), 0 ,(struct sockaddr *)&client,&client_len); //默认会阻塞
		gettime();
        printf("client ip is [%s],time is [%s]:%s\n",inet_ntoa(client.sin_addr),w_buf,buf);
		bzero(buf,sizeof(buf));
	}
	
	return 0;
}


int main(int argc,char *argv[])
{
	//1.创建UDP套接字             
	udp_socket = socket(AF_INET, SOCK_DGRAM, 0);
	if (udp_socket == -1)
	{
		fprintf(stderr, "udp socket error,errno:%d,%s\n",errno,strerror(errno));
		exit(1);
	}
	pthread_t thread;
	pthread_t thread1;
    // pthread_t thread2;
	pthread_create(&thread, NULL, sendm, NULL);
	pthread_create(&thread1, NULL, recvm, NULL);
    // pthread_create(&thread2, NULL, gettime, NULL);

	while(1);
	return 0;
}

结果：