如何使用C/C++获取目录中的文件列表？

#include<iostream>
int main () {
   char command[50] = "ls -l";
   system(command);
   return 0;
}

-rwxrwxrwx 1 root root  9728 Feb 25 20:51 a.out
-rwxrwxrwx 1 root root   131 Feb 25 20:44 hello.cpp
-rwxrwxrwx 1 root root   243 Sep  7 13:09 hello.py
-rwxrwxrwx 1 root root 33198 Jan  7 11:42 hello.o
drwxrwxrwx 0 root root   512 Oct  1 21:40 hydeout
-rwxrwxrwx 1 root root    42 Oct 21 11:29 my_file.txt
-rwxrwxrwx 1 root root   527 Oct 21 11:29 watch.py

#include <iostream>
#include <dirent.h>
#include <sys/types.h>

using namespace std;
void list_dir(const char *path) {
   struct dirent *entry;
   DIR *dir = opendir(path);
   
   if (dir == NULL) {
      return;
   }
   while ((entry = readdir(dir)) != NULL) {
   cout << entry->d_name << endl;
   }
   closedir(dir);
}
int main() {
   list_dir("/home/username/Documents");
}

a.out
hello.cpp
hello.py
hello.o
hydeout
my_file.txt
watch.py