Linux接收udp广播

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define BUF_SIZE 1024

int main() {
    int sockfd;
    struct sockaddr_in servaddr, cliaddr;
    char buffer[BUF_SIZE];

    // 创建UDP套接字
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
        perror("socket creation failed");
        exit(EXIT_FAILURE);
    }

    memset(&servaddr, 0, sizeof(servaddr));
    memset(&cliaddr, 0, sizeof(cliaddr));

    // 配置服务器地址（接收广播的地址）
    servaddr.sin_family = AF_INET;
    servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
    servaddr.sin_port = htons(8888);

    // 允许接收广播
    int broadcastEnable = 1;
    int ret = setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &broadcastEnable, sizeof(broadcastEnable));
    if (ret < 0) {
        perror("setsockopt failed");
        close(sockfd);
        exit(EXIT_FAILURE);
    }

    // 绑定套接字到地址
    if (bind(sockfd, (const struct sockaddr *)&servaddr, sizeof(servaddr)) < 0) {
        perror("bind failed");
        close(sockfd);
        exit(EXIT_FAILURE);
    }

    socklen_t length;

    while (1) {
        length = sizeof(cliaddr);
        int n = recvfrom(sockfd, (char *)buffer, BUF_SIZE, MSG_WAITALL, (struct sockaddr *)&cliaddr, &length);
        if (n < 0) {
            perror("recvfrom failed");
            break;
        }
        buffer[n] = '\0';
        printf("Received broadcast: %s from %s:%d
", buffer, inet_ntoa(cliaddr.sin_addr), ntohs(cliaddr.sin_port));
    }

    close(sockfd);
    return 0;
}