c++ - 分段故障打印文件特征

Question

我正在尝试编写 ls 命令的简单实现，接近 ls -l，但不完全相同。

这是我目前所拥有的

#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <unistd.h>
#include <iostream>
#include <stdio.h>
#include <time.h>

using namespace std;
int main(int argc, char **argv)
{
    if(argc != 2)
    {
        cout << "Usage: ./Asg4 <directoryName>" << endl;
        return -1;
    }

    struct stat sb;
    DIR *d;
    struct dirent *dir;
    d = opendir(argv[1]);

    if(d)
    {
        while((dir = readdir(d)) != NULL)
        {
            stat(dir->d_name, &sb);
            printf("%ld\t %s\t%lo\t%ld\t%lld\t%s\n", sb.st_ino, sb.st_dev, (unsigned long) sb.st_mode, (long) sb.st_nlink, (long long) sb.st_size, ctime(&sb.st_mtime));
        }
        closedir(d);
    }
    return 0;
}

但是当我在任何给定目录上执行它时，它会给我一个段错误。有什么想法吗？

为了响应 Loki Astari 的回答，我将 printf 更改为

printf("%ld\t %d\t%lo\t%ld\t%lld\t%s\n", (long) sb.st_ino, (int) sb.st_dev, (unsigned long) sb.st_mode, (long) sb.st_nlink, (long long) sb.st_size, ctime(&sb.st_mtime));

这似乎解决了段错误。

Answer 1

当我编译时，我收到一些讨厌的警告:

xc.cpp:28:54: warning: format specifies type 'long' but the argument has type '__darwin_ino64_t' (aka 'unsigned long long') [-Wformat]
            printf("%ld\t %s\t%lo\t%ld\t%lld\t%s\n", sb.st_ino, sb.st_dev, (unsigned long) sb.st_mode, (long) sb.st_nlink, (long long) sb.st_size, ctime(&sb.st_mtime));
                    ~~~                              ^~~~~~~~~
                    %llu
xc.cpp:28:65: warning: format specifies type 'char *' but the argument has type 'dev_t' (aka 'int') [-Wformat]
            printf("%ld\t %s\t%lo\t%ld\t%lld\t%s\n", sb.st_ino, sb.st_dev, (unsigned long) sb.st_mode, (long) sb.st_nlink, (long long) sb.st_size, ctime(&sb.st_mtime));
                          ~~                                    ^~~~~~~~~
                          %d

那些看起来像是会崩溃的错误。
这也是使用 C++ 而不是 C 的一个很好的广告。C++ 流没有这个问题。