WordPress at a glance
action is not described

atom_head action-hook . WP 2.0.0

Fires just before the first Atom feed entry.

Usage

add_action( 'atom_head', 'action_function_name_9448' );
function action_function_name_9448(){
	// action...
}

Changelog

Since 2.0.0 Introduced.

Where the hook is called

In file: /wp-includes/feed-atom.php
atom_head
wp-includes/feed-atom.php 45
do_action( 'atom_head' );

Where in WP core the hook is used WordPress

wp-includes/feed-atom.php 324
add_action( $action, 'the_generator' );
wp-includes/feed-atom.php 328
add_action( 'atom_head', 'atom_site_icon' );