atom_ns
atom_ns is an action that is fired in the Atom feed's XML namespace section.
Context:
File: wp-atom.php
<feed version="0.3"
xmlns="http://purl.org/atom/ns#"
xmlns:dc="http://purl.org/dc/elements/1.1/"
xml:lang="<?php echo get_option('rss_language'); ?>"
<?php do_action('atom_ns'); ?>
>
This hook provides no parameters. You use this hook by having your function echo output to the browser, or by having it perform background tasks. Your functions shouldn't return, and shouldn't take any parameters
This hook is an action which means that it primarily acts as an event trigger, instead of a content filter. This is a semantic difference, but it will help you to remember what this hook does if you use it like this: add_action('atom_ns', 'your_function');
This hook was introduced in WordPress 2.0, and will not work in earlier versions.