[hate]

I seen your post about mkdir so this may be what your after

$filecontent="Code For File To Insert";
mkdir('/home/path/public_html/'.$username, 0777);
if ($fp = fopen("/home/path/public_html/".$username."/index.php", "w")) {
	fwrite($fp, $filecontent);
	chmod("/home/path/public_html/".$username."/index.php", 0755);
	fclose($fp);
}