2月14日 网络编程 广播和组播

搭建一个广播接收方

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<arpa/inet.h>

#include<unistd.h>

#include<string.h>

#define PORT 2222

#define IP "192.168.8.255"

//创建报式套接字

int main(int argc, const char *argv[])

{

intsfd=socket(AF_INET,SOCK_DGRAM,0);

if(sfd<0){

perror("socket");

return-1;

}

//服务器的地址信息结构体

structsockaddr_in sin;

sin.sin_family =AF_INET;

sin.sin_port =htons(PORT);

sin.sin_addr.s_addr = inet_addr(IP);

if(bind(sfd,(structsockaddr*)&sin,sizeof(sin))<0)

{

perror("bind");

return-1;

}

printf("serverbind success\n");

charbuf[128]="";

ssize_tres=0;

structsockaddr_in cin;

socklen_taddrlen=sizeof(cin);

while(1)

{

bzero(buf,sizeof(buf));

//接受发来的消息

res=recvfrom(sfd,buf,sizeof(buf),0,(structsockaddr*)&cin,&addrlen);

if(res<0)

{

perror("recvfrom");

return-1;

}

printf("[%s:%d]:%s\n",inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),buf);

}

//关闭套接字文件描述符

close(sfd);

return0;

}

搭建一个广播发送方

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<arpa/inet.h>

#include<unistd.h>

#include<string.h>

#define PORT 2222

#define IP "192.168.8.255"

int main(int argc, const char *argv[])

{

intsfd=socket(AF_INET,SOCK_DGRAM,0);

if(sfd<0){

perror("socket");

return-1;

}

structsockaddr_in sin;

sin.sin_family =AF_INET;

sin.sin_port =htons(PORT);

sin.sin_addr.s_addr = inet_addr(IP);

//设置广播属性

intbro=1;

if(setsockopt(sfd,SOL_SOCKET,SO_BROADCAST,&bro,sizeof(int))<0){

perror("setsockopt");

return-1;

}

printf("serverbind success\n");

charbuf[128]="";

ssize_tres=0;

structsockaddr_in cin;

socklen_taddrlen=sizeof(cin);

while(1)

{

bzero(buf,sizeof(buf));

printf("请输入》》");

fgets(buf,sizeof(buf),stdin);

buf[strlen(buf)-1]=0;

//发送的消息

if(sendto(sfd,buf,sizeof(buf),0,(structsockaddr*)&sin,sizeof(sin))<0)

{

perror("sendto");

return-1;

}

printf("sendtosuccess\n");

//关闭套接字文件描述符

}

close(sfd);

return0;

}

搭建一个组播接收方

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<arpa/inet.h>

#include<unistd.h>

#include<string.h>

#include<net/if.h>

#define PORT4444

#define IP"224.1.1.1"

//创建报式套接字

int main(intargc, const char *argv[])

{

int sfd=socket(AF_INET,SOCK_DGRAM,0);

if(sfd<0){

perror("socket");

return -1;

}

//服务器的地址信息结构体

struct sockaddr_in sin;

sin.sin_family =AF_INET;

sin.sin_port =htons(PORT);

sin.sin_addr.s_addr = inet_addr(IP);

//绑定自身的地址信息结构体

if(bind(sfd,(structsockaddr*)&sin,sizeof(sin))<0)

{

perror("bind");

return -1;

}

printf("server bind success\n");

struct ip_mreqn zubo;

zubo.imr_multiaddr.s_addr=inet_addr(IP);

zubo.imr_address.s_addr=inet_addr("192.168.8.99");

zubo.imr_ifindex=if_nametoindex("en37");

if(setsockopt(sfd,IPPROTO_IP,IP_ADD_MEMBERSHIP,&zubo,sizeof(zubo))<0){

perror("setsockopt");

return -1;

}

printf("加入多播组成功！");

char buf[128]="";

ssize_t res=0;

struct sockaddr_in cin;

socklen_t addrlen=sizeof(cin);

while(1)

{

//将数据7发送给服务器

bzero(buf,sizeof(buf));

//接受服务器发来的消息

res=recvfrom(sfd,buf,sizeof(buf),0,(structsockaddr*)&cin,&addrlen);

if(res<0)

{

perror("recvfrom");

return -1;

}

printf("[%s:%d]:%s\n",inet_ntoa(cin.sin_addr),ntohs(cin.sin_port),buf);

}

//关闭套接字文件描述符

close(sfd);

return 0;

}

搭建一个组播发送方

#include<stdio.h>

#include<sys/types.h>

#include<sys/socket.h>

#include<netinet/in.h>

#include<arpa/inet.h>

#include<unistd.h>

#include<string.h>

#define PORT 4444

#define IP "224.1.1.1"

int main(int argc, const char *argv[])

{

intsfd=socket(AF_INET,SOCK_DGRAM,0);

if(sfd<0){

perror("socket");

return-1;

}

structsockaddr_in sin;

sin.sin_family =AF_INET;

sin.sin_port =htons(PORT);

sin.sin_addr.s_addr = inet_addr(IP);

charbuf[128]="";

ssize_tres=0;

while(1)

{

bzero(buf,sizeof(buf));

printf("请输入》》");

fgets(buf,sizeof(buf),stdin);

buf[strlen(buf)-1]=0;

//发送的消息

if(sendto(sfd,buf,sizeof(buf),0,(structsockaddr*)&sin,sizeof(sin))<0)

{

perror("sendto");

return-1;

}

printf("sendtosuccess\n");

//关闭套接字文件描述符

}

close(sfd);

return0;

}