/**
 * Implements hook_menu_update().
 */
function {{ machine_name }}_menu_update($menu) {
  // For example, we track available menus in a variable.
  $my_menus = variable_get('my_module_menus', array());
  $my_menus[$menu['menu_name']] = $menu['menu_name'];
  variable_set('my_module_menus', $my_menus);
}