wp-includes/class-wp-user.php:870Sets the site to operate on. Defaults to the current site.
$site_idintoptional'' public function for_site( $site_id = '' ) { global $wpdb; if ( ! empty( $site_id ) ) { $this->site_id = absint( $site_id ); } else { $this->site_id = get_current_blog_id(); } $this->cap_key = $wpdb->get_blog_prefix( $this->site_id ) . 'capabilities'; $this->caps = $this->get_caps_data(); $this->get_role_caps(); }Introduced in 4.9.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-user.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.