Creating a uniqd id for users upload folder name

Hi, I am just trying to get some ideas what best and whats not.

I was thinking when user creates a new account it also creates a upload folder for that user using its date_joined time()

The users folder would be in time() format

PHP Code:

$userdata = $this->user_model->getuser($this->user_model->getuserid());

if (!is_dir(FCPATH . 'uploads/' . $userdata['date_created'])) {
    mkdir(FCPATH . 'uploads/' . $userdata['date_created'], 0777, true);
} 


Out put

PHP Code:

C:\xampp\htdocs\project\uploads/1487475460 


Is that OK or if you have any other suggestions

There's only one rule - please don't tell anyone to go and read the manual.  Sometimes the manual just SUCKS!