Retrieves the URL for a given site where the front end is accessible.

Returns the ‘home’ option with the appropriate protocol. The protocol will be ‘https’ if is_ssl() evaluates to true; otherwise, it will be the same as the ‘home’ option. If `$scheme` is ‘http’ or ‘https’, is_ssl() is overridden.

Signature

get_home_url( $blog_id = null, $path = '', $scheme = null )
blog_id
 (int) Optional. Site ID. Default null (current site).
Default: null
path
 (string) Optional. Path relative to the home URL. Default empty.
Default: ''
scheme
 (string|null) Optional. Scheme to give the home URL context. Accepts 'http', 'https', 'relative', 'rest', or null. Default null.
Default: null

Return

(string) Home URL link with optional path appended.

Source

function get_home_url( $blog_id = null, $path = '', $scheme = null ) {
	global $pagenow;

	$orig_scheme = $scheme;

	if ( empty( $blog_id ) || !is_multisite() ) {
		$url = get_option( 'home' );
	} else {
		switch_to_blog( $blog_id );
		$url = get_option( 'home' );
		restore_current_blog();
	}

	if ( ! in_array( $scheme, array( 'http', 'https', 'relative' ) ) ) {
		if ( is_ssl() && ! is_admin() && 'wp-login.php' !== $pagenow )
			$scheme = 'https';
		else
			$scheme = parse_url( $url, PHP_URL_SCHEME );
	}

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