Linux下的广播程序

        最近需要用到网络编程中的广播程序，在网上找了下，亲测可用。

客户端：

#include <stdio.h>
#include <arpa/inet.h>
#include <string.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <unistd.h>


int main(void)
{
    struct sockaddr_in all;
    int fd;
    //广播消息
    char buff[]="this is a broadcast message";
    int so_boradcast=1;

    //IPv4 UDP
    fd=socket(AF_INET,SOCK_DGRAM,0);
    //广播地址，用ifconfig查看得到
    all.sin_addr.s_addr=inet_addr("192.168.1.255");
    all.sin_family=AF_INET;
    //端口号
    all.sin_port=htons(8888);
    //设置socket为广播
    setsockopt(fd,SOL_SOCKET,SO_BROADCAST,&so_boradcast,sizeof(so_boradcast));

    while(1)
    {
        //广播
        sendto(fd,buff,strlen(buff),0,(struct sockaddr *)&all,sizeof(all));
        //延时1秒
        sleep(1);
    }
    return 0;
}

服务器端：

#include <stdio.h>
#include <arpa/inet.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc,char *argv[])
{
    int fd;
    struct sockaddr_in server;
    struct sockaddr_in client;
    int status;

    //IPv4 UDP
    fd=socket(AF_INET,SOCK_DGRAM,0);
    //端口号
    server.sin_port=htons(8888);
    server.sin_addr.s_addr=INADDR_ANY;
    server.sin_family=AF_INET;

    //绑定地址
    status=bind(fd,(struct sockaddr *)&server,sizeof(struct sockaddr));
    if(status<0)
    {
        printf(" bind() error\n");
        exit(1);
    }
    //接收Buffer
    char buff[1024];
    socklen_t len=sizeof(struct sockaddr);

    while(1)
    {
        //接收
        recvfrom(fd,buff,1024,0,(struct sockaddr *)&client,&len);
        //打印接收到的信息
        printf("%s\n",buff);
    }

    return 0;
}