WordPress at a glance
action is not described

rss_head action-hook . WP 2.0.0

Fires at the end of the RSS Feed Header.

Usage

add_action( 'rss_head', 'action_function_name_2334' );
function action_function_name_2334(){
	// action...
}

Where the hook is called

In file: /wp-includes/feed-rss.php
rss_head
wp-includes/feed-rss.php 30
do_action( 'rss_head' );

Where the hook is used (in WP core)

Does not used.