udp广播的例子-编程知识

udp广播的例子

在这里插入图片描述

以下是一个使用C语言描述广播发送和接收的简单示例：

发送端（广播发送）：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>#define BROADCAST_PORT 8888
#define BROADCAST_ADDRESS "192.168.1.255"  // 替换为您的广播地址int main() {int sockfd;struct sockaddr_in broadcastAddr;char *broadcastMsg = "Hello, broadcast!";// 创建UDP套接字if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {perror("socket creation failed");exit(EXIT_FAILURE);}// 设置广播选项int broadcastEnable = 1;if (setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &broadcastEnable, sizeof(broadcastEnable)) < 0) {perror("setsockopt failed");exit(EXIT_FAILURE);}// 设置广播地址和端口memset(&broadcastAddr, 0, sizeof(broadcastAddr));broadcastAddr.sin_family = AF_INET;broadcastAddr.sin_port = htons(BROADCAST_PORT);if (inet_pton(AF_INET, BROADCAST_ADDRESS, &broadcastAddr.sin_addr) <= 0) {perror("inet_pton failed");exit(EXIT_FAILURE);}// 发送广播消息if (sendto(sockfd, broadcastMsg, strlen(broadcastMsg), 0, (struct sockaddr*)&broadcastAddr, sizeof(broadcastAddr)) < 0) {perror("sendto failed");exit(EXIT_FAILURE);}printf("Broadcast message sent.\n");close(sockfd);return 0;
}

接收端（广播接收）：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>#define BROADCAST_PORT 8888int main() {int sockfd;struct sockaddr_in myAddr, senderAddr;char recvBuffer[1024];socklen_t senderLen = sizeof(senderAddr);// 创建UDP套接字if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {perror("socket creation failed");exit(EXIT_FAILURE);}// 设置接收端地址和端口memset(&myAddr, 0, sizeof(myAddr));myAddr.sin_family = AF_INET;myAddr.sin_addr.s_addr = htonl(INADDR_ANY);myAddr.sin_port = htons(BROADCAST_PORT);// 绑定套接字到接收端地址if (bind(sockfd, (struct sockaddr*)&myAddr, sizeof(myAddr)) < 0) {perror("bind failed");exit(EXIT_FAILURE);}// 接收广播消息if (recvfrom(sockfd, recvBuffer, sizeof(recvBuffer)-1, 0, (struct sockaddr*)&senderAddr, &senderLen) < 0) {perror("recvfrom failed");exit(EXIT_FAILURE);}// 打印接收到的广播消息printf("Received broadcast message: %s\n", recvBuffer);close(sockfd);return 0;
}