多播的測試代碼如下：

#include <stdio.h> #include <string.h> #include <stdlib.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <arpa/inet.h>#define PORT 10086 #define SIZE 128int main(void) {int ret = -1;int sockfd = -1;int i = 0;char buf[SIZE];struct sockaddr_in addr;struct sockaddr_in from;//組播相關結構體struct ip_mreq req;socklen_t len = sizeof(from);sockfd = socket(AF_INET, SOCK_DGRAM, 0);if (-1 == sockfd){perror("socket"); goto err0;}memset(&addr, 0, sizeof(addr));addr.sin_family = AF_INET;addr.sin_port = htons(PORT);addr.sin_addr.s_addr = INADDR_ANY;//inet_pton(AF_INET, "172.16.1.88", &addr.sin_addr); ret = bind(sockfd, (void*)&addr, sizeof(addr));if (-1 == ret){perror("bind"); goto err1;}printf("UDP Server %s: %d\n", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));//加入多播組req.imr_multiaddr.s_addr = inet_addr("224.0.0.88");//將本機加入多播組req.imr_interface.s_addr = INADDR_ANY;//加入多播組ret = setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &req, sizeof(req));if (ret < 0){perror("setsockopt"); goto err0;}while(1){memset(buf, 0, SIZE);ret = recvfrom(sockfd, buf, SIZE, 0, (void*)&from, &len);buf[ret] = 0;printf("recv from: %s:%d %s\n", inet_ntoa(from.sin_addr), ntohs(from.sin_port), buf);i++;//退出循環if (10 == i)break;}ret = setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &req, sizeof(req));if (ret < 0){perror("setsockopt"); goto err0;}//退出組播組之后 測試是否可以收到組播包while(1){memset(buf, 0, SIZE);ret = recvfrom(sockfd, buf, SIZE, 0, (void*)&from, &len);buf[ret] = 0;printf("recv from: %s:%d %s\n", inet_ntoa(from.sin_addr), ntohs(from.sin_port), buf);i++;//退出循環if (10 == i)break;}close(sockfd);return 0; err1:close(sockfd); err0:return -1; }

在ubuntu編譯運行時，出現如下的錯誤：

查詢相關資料得到的答案如下：

It means that the tool is trying to use multicast but the network interface doesn't support it There are two likely causes:
·Your machine doesn't have multicast support enabled. For example, on Linux and FreeBSD it is possible to compile a kernel which doesn't support multicast. ?
·You don't have a route for multicast traffic. Some systems don't add this by default, and you need to run：
route add -net 224.0.0.0 netmask 255.255.255.255 eth0(or similar). If you wish to use RAT in unicast mode only, it is possible to add the multicast route on the loopback interface.

這主要和當前的網絡配置有關，因為多播IP地址沒有加入到路由表中。

解決方法：把需要用到的多播地址(如本例的224.0.0.88)加入到路由表中，命令如下：

sudo route add -net?224.0.0.88?netmask 255.255.255.255 eth0

224.0.0.88：為當前使用的多播IP地址

eth0：為當前使用的有效網卡

其它輔助命令：

sudo route del -net 224.0.0.88 netmask 255.255.255.255 eth0?//把224.0.0.88從路由表中刪除

route -n?//查看路由表信息

具體操作過程如下圖：

總結

以上是生活随笔為你收集整理的【Linux网络编程】Linux多播问题（No such device）解决方法的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。