WordPress at a glance
action is not described

network_admin_menu action-hook . WP 3.1.0

Fires before the administration menu loads in the Network Admin.

Usage

add_action( 'network_admin_menu', 'action_function_name_9387' );
function action_function_name_9387( $context ){
	// action...
}
$context(string)
Empty context.

Where the hook is called

In file: /wp-admin/includes/menu.php
network_admin_menu
wp-admin/includes/menu.php 129
do_action( 'network_admin_menu', '' );

Where the hook is used (in WP core)

Does not used.