code: func (udevWatcher *UdevWatcher) buildState(links []netlink.Link) map[string]string {
  	state := make(map[string]string)
  	for _, link := range links {
  		if link.Type() != linkTypeDevice {
  			// We only care about netlink.Device types. These are created
  			// by udev like 'lo' and 'eth0'. Ignore other link types
  			continue
  		}
  		if link.Attrs().EncapType == encapTypeLoopback {
  			// Ignore localhost
  			continue
  		}
  		macAddress := link.Attrs().HardwareAddr.String()
  		if macAddress != "" && macAddress != udevWatcher.primaryMAC {
  			state[macAddress] = link.Attrs().Name
  		}
  	}
  	return state
  }
docs: // buildState is used to build a state of the system for reconciliation