const blackholeRepresentation … const blackholeIfaceName … const routeLineColumns … type NetRouteLine … func (fs FS) NetRoute() ([]NetRouteLine, error) { … } func readNetRoute(path string) ([]NetRouteLine, error) { … } func parseNetRoute(r io.Reader) ([]NetRouteLine, error) { … } func parseNetRouteLine(fields []string) (*NetRouteLine, error) { … }