linux的UDP广播测试:C语言代码

news2025/4/25 12:14:09

测试代码

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

#define DEBUG_INFO(fmt, ...) printf("[%s:%d] " fmt "\n", __FUNCTION__, __LINE__, ##__VA_ARGS__)

int main(int argc, char *argv[]) {
    int sockfd;
    struct sockaddr_in local,serv_addr, cli_addr;
    socklen_t clilen;
    // char *hello = "Hello, i am imx8255 255 255 255 !";
    // char *hello = "255.255.255.255";
    char *hello = "192.168.255.255";
    // char *hello = "192.168.0.255";



    int broadcast = 1;
    int optval = 1;
    DEBUG_INFO("starting");

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

    // 设置socket选项以允许广播
    if (setsockopt(sockfd, SOL_SOCKET, SO_BROADCAST, &optval, sizeof optval) < 0) {
        perror("setsockopt (SO_BROADCAST) failed");
        exit(EXIT_FAILURE);
    }
    // 设置服务端的地址和端口  
    local.sin_family = AF_INET;  
    // 假设你想绑定到本地的IP地址 "192.168.1.100"，你可以通过inet_addr或inet_pton来设置  
    local.sin_addr.s_addr = inet_addr("192.168.0.3");  
    // 或者使用inet_pton来处理IPv6地址  
    // if (inet_pton(AF_INET, "192.168.0.3", &serv_addr.sin_addr) <= 0) {  
    //     perror("inet_pton failed");  
    //     exit(EXIT_FAILURE);  
    // }  
    local.sin_port = htons(12345); // 假设端口是12345  
  
    // 绑定socket到本地地址和端口  
    if (bind(sockfd, (struct sockaddr *)&local, sizeof(local)) < 0) {  
        perror("bind failed");  
        exit(EXIT_FAILURE);  
    } 
    DEBUG_INFO("1");

    // 设置目标地址和端口
    memset((char *) &serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    // serv_addr.sin_addr.s_addr = inet_addr("255.255.255.255"); // 广播地址
    // serv_addr.sin_addr.s_addr = inet_addr("192.168.0.255"); // 广播地址
    serv_addr.sin_addr.s_addr = inet_addr(hello); // 广播地址
    serv_addr.sin_port = htons(9990); // 目标端口

    DEBUG_INFO("2");

    // 发送广播消息
    if (sendto(sockfd, (const char *)hello, strlen(hello), MSG_CONFIRM,
               (const struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0) {
        perror("sendto failed");
        exit(EXIT_FAILURE);
    }

    printf("Hello message sent to broadcast address\n");

    close(sockfd);
    return 0;
}

交叉编译脚本：

#!/bin/bash

echo "hello"
source /opt/fsl-imx-xwayland/5.4-zeus/environment-setup-aarch64-poky-linux
echo $ARCH
aarch64-poky-linux-gcc --sysroot=/opt/fsl-imx-xwayland/5.4-zeus/sysroots/aarch64-poky-linux broad.c -o broad
sudo cp broad /home/lkmao/nfsroot/yocto/home/root/
#make
exit 0