code: func (h *Handle) RouteList(link Link, family int) ([]Route, error) {
  	var routeFilter *Route
  	if link != nil {
  		routeFilter = &Route{
  			LinkIndex: link.Attrs().Index,
  		}
  	}
  	return h.RouteListFiltered(family, routeFilter, RT_FILTER_OIF)
  }
docs: // RouteList gets a list of routes in the system.
  // Equivalent to: `ip route show`.
  // The list can be filtered by link and ip family.