creating directory via php

does anyone know a script where it can create a directory automatically in your root folder...ex. myurl.com/newdirhere

newdirhere being the username that was inputed in a form field.
something similar to like a geocities website.

and have it also include a filemanager and other files as directed??

thanks. J

Syntax:
mkdir ( string pathname, int mode )

Example:
mkdir ("/path/to/my/dir", 0700);

what about copying a file /folder fromm another directory and placing it in the newly created directory??