izziv5.c

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>

void ls(char const *path) {
  DIR* dir = opendir(path);

  struct dirent *entry;
  if(dir != NULL) {
    printf("Listing directory %s:\n", path);
    while((entry = readdir(dir)))
      puts(entry->d_name);
    closedir (dir);
  }
  else
    printf("Path %s isn't a directory!\n", path);
}

int main(int argc, char const *argv[]) {
  if(argv[1])
    ls(argv[1]);
  else
    ls("./");

  return 0;
}