_network_admin_menu action-hook . WP 3.1.0
Fires before the administration menu loads in the Network Admin.
The hook fires before menus and sub-menus are removed based on user privileges.
Usage
add_action( '_network_admin_menu', 'action_function_name_3369' );
function action_function_name_3369(){
// action...
}Where the hook is called
In file:
/wp-admin/includes/menu.php_network_admin_menu
wp-admin/includes/menu.php 19
do_action( '_network_admin_menu' );