FlagRunning                        // interface is in running state
)

var flagNames = []string{
	"up",
	"broadcast",
	"loopback",
	"pointtopoint",
	"multicast",
	"running",
}

func (f Flags) String() string {
	s := ""
	for i, name := range flagNames {
		if f&(1<<uint(i)) != 0 {
			if s != "" {
				s += "|"
			}
			s += name
		}

	var ipPointToPoint bool
	// Seems like we need to make sure whether the IP interface
	// stack consists of IP point-to-point numbered or unnumbered
	// addressing.
	for _, a := range attrs {
		if a.Attr.Type == syscall.IFA_LOCAL {
			ipPointToPoint = true
			break
		}
	}
	for _, a := range attrs {
		if ipPointToPoint && a.Attr.Type == syscall.IFA_ADDRESS {
			continue

	} else {
		return family == familyIPv6
	}
}

// chooseIPFromHostInterfaces looks at all system interfaces, trying to find one that is up that
// has a global unicast address (non-loopback, non-link local, non-point2point), and returns the IP.
// addressFamilies determines whether it prefers IPv4 or IPv6
func chooseIPFromHostInterfaces(nw networkInterfacer, addressFamilies AddressFamilyPreference) (net.IP, error) {
	intfs, err := nw.Interfaces()