用C实现ls -t选项

#include <stdio.h>
#include <stdlib.h>
#include <dirent.h>
#include <sys/stat.h>
#include <time.h>

typedef struct {
    char *name;
    time_t mtime;
} FileInfo;

int compare(const void *a, const void *b) {
    FileInfo *fileA = (FileInfo *)a;
    FileInfo *fileB = (FileInfo *)b;
    return difftime(fileB->mtime, fileA->mtime); // 降序排序
}

void list_files_sorted_by_time(const char *dir_path) {
    DIR *dir;
    struct dirent *entry;
    struct stat file_stat;
    FileInfo files[1024];
    int file_count = 0;

    if ((dir = opendir(dir_path)) == NULL) {
        perror("opendir");
        return;
    }

    while ((entry = readdir(dir)) != NULL && file_count < 1024) {
        char full_path[1024];
        snprintf(full_path, sizeof(full_path), "%s/%s", dir_path, entry->d_name);
        if (stat(full_path, &file_stat) == 0 && S_ISREG(file_stat.st_mode)) {
            files[file_count].name = strdup(entry->d_name);
            files[file_count].mtime = file_stat.st_mtime;
            file_count++;
        }
    }
    closedir(dir);

    qsort(files, file_count, sizeof(FileInfo), compare);

    for (int i = 0; i < file_count; i++) {
        printf("%s\n", files[i].name);
        free(files[i].name);
    }
}

int main(int argc, char *argv[]) {
    if (argc != 2) {
        fprintf(stderr, "Usage: %s <directory>\n", argv[0]);
        return 1;
    }

    list_files_sorted_by_time(argv[1]);
    return 0;
}

if (stat(full_path, &file_stat) != 0) {
    perror("stat");
    continue;
}