Linux网络编程-UDP单播服务客户端代码实现

1、服务端

只接收一个字符串

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
 
#define BUF_SIZE 88
#define PORT     55555
 
int main(int argc, char *argv[])
{
    //建立套接字
    int sock_fd = socket(AF_INET, SOCK_DGRAM, 0);           //IPV4,数据报套接字类型,不指定协议
 
    //说明本服务器地址
  /*  const struct sockaddr_in srvaddr = {
        .sin_family = AF_INET,                              //协议类型IPV4
        .sin_port = htons(PORT),                            //端口号-网络字节序
        .sin_addr.s_addr = htonl(INADDR_ANY)                //IP地址-任意地址
    };*/
  struct sockaddr_in srvaddr;
    srvaddr.sin_family = AF_INET;                              //协议类型IPV4
    srvaddr.sin_port = htons(PORT);                            //端口号-网络字节序
    srvaddr.sin_addr.s_addr = htonl(INADDR_ANY);               //IP地址-任意地址

 
    //绑定地址
    bind(sock_fd, (const struct sockaddr *)&srvaddr, sizeof(srvaddr));
 
    //接收数据
    char buf[BUF_SIZE] = { 0 };
    struct sockaddr_in cliaddr;
    socklen_t cliaddrlen = sizeof(cliaddr);
    while (1)
    {
        bzero(buf, BUF_SIZE);
        bzero(&cliaddr, cliaddrlen);
        recvfrom(sock_fd, buf, BUF_SIZE, 0, (struct sockaddr *)&cliaddr, &cliaddrlen);
        printf("udp server from [%s - %hu]:%s\n",inet_ntoa(cliaddr.sin_addr),cliaddr.sin_port,buf);
    }
 
    //关闭套接字
    close(sock_fd);
 
    return 0;
}

2、客户端

#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
 
#define BUF_SIZE 88
#define PROT     55555
#define ADDR     "192.168.111.213"
 
int main(int argc, char *argv[])
{
    //建立套接字
    int sock_fd = socket(AF_INET, SOCK_DGRAM, 0);           //IPV4,数据报套接字类型,不指定协议
 
    //声明将连接地址
 /*   const struct sockaddr_in  srvaddr = {
        .sin_family = AF_INET,                              //协议类型IPV4
        .sin_port = htons(PROT),                            //端口号-网络字节序
        .sin_addr.s_addr = inet_addr(ADDR)                  //IP地址-字符串转IP
    };*/
  //声明将连接地址
    struct sockaddr_in  srvaddr;
       srvaddr.sin_family = AF_INET;                              //协议类型IPV4
        srvaddr.sin_port = htons(PROT);                            //端口号-网络字节序
        srvaddr.sin_addr.s_addr = inet_addr(ADDR);                  //IP地址-字符串转IP
        
    //发送数据
    char buf[BUF_SIZE] = { 0 };
	int count = 0;
    while (1)
    {
        memset(buf,0, BUF_SIZE);
        sprintf(buf, "%d",count);//每次发一个字符串
		printf("udp client send:[%s - %d]:%s\n",ADDR,PROT,buf);
        sendto(sock_fd, buf, strlen(buf), 0, (const struct sockaddr*)&srvaddr, sizeof(srvaddr));
		count++;
		sleep(1);
    }
 
    //关闭套接字
    close(sock_fd);
 
    return 0;
}