code: func FirewalldInit() error {
  	var err error
  
  	if connection, err = newConnection(); err != nil {
  		return fmt.Errorf("Failed to connect to D-Bus system bus: %v", err)
  	}
  	firewalldRunning = checkRunning()
  	if !firewalldRunning {
  		connection.sysconn.Close()
  		connection = nil
  	}
  	if connection != nil {
  		go signalHandler()
  	}
  
  	return nil
  }
docs: // FirewalldInit initializes firewalld management code.