How to extract hostname from url.

[hamburglar]

Hello, want to extract the domain from the referer url so it if is:

http://www.domain.com/somepage.html

I want to get just:

domain.com


I haven't a clue how to do it. Thanks.

[logic_earth]

print $_SERVER['HTTP_HOST']; // www.domain.com 

or

http://www.php.net/manual/en/function.parse-url.php