WordPress at a glance
filter is not described

login_headerurl filter-hook . WP 2.1.0

Filters link URL of the header logo above login form.

Usage

add_filter( 'login_headerurl', 'filter_function_name_8502' );
function filter_function_name_8502( $login_header_url ){
	// filter...

	return $login_header_url;
}
$login_header_url(string)
Login header logo URL.

Where the hook is called

login_header()
login_headerurl
wp-login.php 131
$login_header_url = apply_filters( 'login_headerurl', $login_header_url );

Where the hook is used (in WP core)

Does not used.