core_upgrade_preamble action-hook . WP 2.9.0

Fires after the core, plugin, and theme update tables.

Usage

add_action( 'core_upgrade_preamble', 'action_function_name_3817' );
function action_function_name_3817(){
	// action...
}

Where the hook is called

do_action( 'core_upgrade_preamble' );

Where the hook is used (in WP core)