apply_filters( 'site_url', string $url, string $path, string|null $scheme, int|null $blog_id )

Parameters

$url

The complete site URL including scheme and path.

$path

Path relative to the site URL. Blank string if no path is specified.

$scheme

Scheme to give the site URL context. Accepts 'http', 'https', 'login', 'login_post', 'admin', 'relative' or null.

$blog_id

Site ID, or null for the current site.