private function autodetect_home() {
		if ($this->home !== null)
			return;
		if (php_sapi_name() == 'cli')
			return $this->home = '/';
		$home = dirname($_SERVER['SCRIPT_NAME']);
		$home = !$home || $home[0] != '/'
			? '/' : rtrim($home, '/') . '/';
		$this->home = $home;
	}