C:检查文件的类型.使用lstat()和宏不起作用

#include <sys/types.h>
#include <sys/stat.h>
#include<stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
    struct stat file_stat;
    int result;

    if (argc != 2) {
        fprintf(stderr, "Usage: %s <path>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    result = lstat(argv[1], &file_stat);
    if (result == -1) {
        perror("lstat");
        exit(EXIT_FAILURE);
    }

    if (S_ISREG(file_stat.st_mode)) {
        printf("Regular file\n");
    } else if (S_ISDIR(file_stat.st_mode)) {
        printf("Directory\n");
    } else if (S_ISCHR(file_stat.st_mode)) {
        printf("Character device\n");
    } else if (S_ISBLK(file_stat.st_mode)) {
        printf("Block device\n");
    } else if (S_ISFIFO(file_stat.st_mode)) {
        printf("FIFO\n");
    } else if (S_ISLNK(file_stat.st_mode)) {
        printf("Symbolic link\n");
    } else if (S_ISSOCK(file_stat.st_mode)) {
        printf("Socket\n");
    } else {
        printf("Unknown file type\n");
    }

    exit(EXIT_SUCCESS);
}