A more proper way to get the domain.tld from an email address in php

[PHP] Get Domain From Email Address (multiple @ symbol support)

// too many php developers use the example on the php `strstr` page:
// http://php.net/manual/en/function.strstr.php
// Yet, amazingly, the following is a valid email address:
// foo@[email protected]
// If you use the example on the strstr page you end up with:
// @[email protected] -- which is of course not what you want.
// So what is a fast and extremely low memory method to return
// just the domain.tld when? The following seems to be the best.

$email = 'foo@[email protected]';

$domain = substr(strrchr($email, "@"), 1);