wp-includes/link-template.php:3739Retrieves the site URL for the current network.
$pathstringoptional''$schemestring|nulloptionalnullstringOne hook fires while network_site_url() runs, in this order:
function network_site_url( $path = '', $scheme = null ) { if ( ! is_multisite() ) { return site_url( $path, $scheme ); } $current_network = get_network(); if ( 'relative' === $scheme ) { $url = $current_network->path; } else { $url = set_url_scheme( 'http://' . $current_network->domain . $current_network->path, $scheme ); } if ( $path && is_string( $path ) ) { $url .= ltrim( $path, '/' ); } /** * Filters the network site URL. * * @since 3.0.0 * * @param string $url The complete network site URL including scheme and path. * @param string $path Path relative to the network site URL. Blank string if * no path is specified. * @param string|null $scheme Scheme to give the URL context. Accepts 'http', 'https', * 'relative' or null. */ return apply_filters( 'network_site_url', $url, $path, $scheme );}Introduced in 3.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/link-template.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.