WordPress at a glance
filter is not described

set_url_scheme filter-hook . WP 3.4.0

Filters the resulting URL after setting the scheme.

Usage

add_filter( 'set_url_scheme', 'filter_function_name_8356', 10, 3 );
function filter_function_name_8356( $url, $scheme, $orig_scheme ){
	// filter...

	return $url;
}
$url(string)
The complete URL including scheme and path.
$scheme(string)
Scheme applied to the URL. One of 'http', 'https', or 'relative'.
$orig_scheme(string/null)
Scheme requested for the URL. One of 'http', 'https', 'login', 'login_post', 'admin', 'relative', 'rest', 'rpc', or null.

Where the hook is called

set_url_scheme()
wp-includes/link-template.php 3412
return apply_filters( 'set_url_scheme', $url, $scheme, $orig_scheme );

Where the hook is used (in WP core)

Does not used.