public function getApacheCtl()
    {
        if ($this->apachectl === false) {
            $shell = new CNabuShell();
            $response = array();
            if ($shell->exec('whereis apachectl', null, $response) && count($response) === 1) {
                $parts = preg_split('/\\s/', preg_replace('/^apachectl: /', '', $response[0]));
                $this->apachectl = $parts[0];
            }
        }

        return $this->apachectl;
    }