ipList = set.NewStringSet()
	for _, ip := range mustGetLocalIPs() {
		if ip.To4() != nil {
			ipList.Add(ip.String())
		}
	}
	return ipList
}

// mustGetLocalIP6 returns IPv6 addresses of localhost.  It panics on error.
func mustGetLocalIP6() (ipList set.StringSet) {
	ipList = set.NewStringSet()
	for _, ip := range mustGetLocalIPs() {
		if ip.To4() == nil {
			ipList.Add(ip.String())
		}
	}