#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>

#define MAXLEN 1024

int main (int argc, char *argv[]) {
   struct dirent *dp;
   char   dent[MAXLEN];   // directory entry

   const char *path="/";

   if ( argc > 1 ) {
      path = argv[1];
   }

   DIR *dir = opendir(path);

   while ((dp=readdir(dir)) != NULL) {
      snprintf(dent, sizeof(dent), "%s/%s", path, dp->d_name);
      printf("%s\n", dent);
   }
   closedir(dir);
   return 0;
}