帮我写一段C语言代码从一个主的udp服务中接收数据并打印

好的，以下是C语言代码示例：

#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 argc, char *argv[]) {
    if (argc < 2) {
        fprintf(stderr, "Usage: %s <port>\n", argv[0]);
        exit(1);
    }

    int port = atoi(argv[1]);

    int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
    if (sockfd < 0) {
        perror("socket failed");
        exit(1);
    }

    struct sockaddr_in addr;
    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_addr.s_addr = htonl(INADDR_ANY);
    addr.sin_port = htons(port);

    if (bind(sockfd, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
        perror("bind failed");
        exit(1);
    }

    char buf[BUF_SIZE];
    while (1) {
        ssize_t n = recv(sockfd, buf, BUF_SIZE - 1, 0);
        if (n < 0) {
            perror("recv failed");
            exit(1);
        }

        buf[n] = '\0';
        printf("Received message: %s\n", buf);
    }

    close(sockfd);
    return 0;
}

这段代码创建了一个UDP套接字，绑定在指定端口上，并循环接收来自客户端的数据，打印输出。