func AscIfNetworkSize(p1Ptr, p2Ptr *IfAddr) int {
	return AscNetworkSize(&p1Ptr.SockAddr, &p2Ptr.SockAddr)
}
AscIfNetworkSize is a sorting function to sort IfAddrs by their respective
network mask size.
package sockaddr
import (
	"encoding/binary"
	"errors"
	"fmt"
	"math/big"
	"net"
	"regexp"
	"sort"
	"strconv"
	"strings"
)
var (
	signRE       *regexp.Regexp = regexp.MustCompile(`^[\s]*[+-]`)
	whitespaceRE *regexp.Regexp = regexp.MustCompile(`[\s]+`)
	ifNameRE     *regexp.Regexp = regexp.MustCompile(`^(?:Ethernet|Wireless LAN) adapter ([^:]+):`)
	ipAddrRE     *regexp.Regexp = regexp.MustCompile(`^   IPv[46] Address\. \. \. \. \. \. \. \. \. \. \. : ([^\s]+)`)
)
type IfAddrs []IfAddr
func (ifs IfAddrs) Len() int { return len(ifs) }
type CmpIfAddrFunc func(p1, p2 *IfAddr) int
type multiIfAddrSorter struct {
	ifAddrs IfAddrs
	cmp     []CmpIfAddrFunc
}
func (ms *multiIfAddrSorter) Sort(ifAddrs IfAddrs) {
	ms.ifAddrs = ifAddrs
	sort.Sort(ms)
}
func OrderedIfAddrBy(cmpFuncs ...CmpIfAddrFunc) *multiIfAddrSorter {
	return &multiIfAddrSorter{
		cmp: cmpFuncs,
	}
}
func (ms *multiIfAddrSorter) Len() int {
	return len(ms.ifAddrs)
}
func (ms *multiIfAddrSorter) Less(i, j int) bool {
	p, q := &ms.ifAddrs[i], &ms.ifAddrs[j]
	var k int
	for k = 0; k < len(ms.cmp)-1; k++ {
		cmp := ms.cmp[k]
		x := cmp(p, q)
		switch x {
		case -1:
			return true
		case 1:
			return false
		}
	}
	switch ms.cmp[k](p, q) {
	case -1:
		return true
	case 1:
		return false
	default:
		return false
		panic("undefined sort order for remaining items in the list")
	}
}
func (ms *multiIfAddrSorter) Swap(i, j int) {
	ms.ifAddrs[i], ms.ifAddrs[j] = ms.ifAddrs[j], ms.ifAddrs[i]
}
func AscIfAddress(p1Ptr, p2Ptr *IfAddr) int {
	return AscAddress(&p1Ptr.SockAddr, &p2Ptr.SockAddr)
}
func AscIfDefault(p1Ptr, p2Ptr *IfAddr) int {
	ri, err := NewRouteInfo()
	if err != nil {
		return sortDeferDecision
	}
	defaultIfName, err := ri.GetDefaultInterfaceName()
	if err != nil {
		return sortDeferDecision
	}
	switch {
	case p1Ptr.Interface.Name == defaultIfName && p2Ptr.Interface.Name == defaultIfName:
		return sortDeferDecision
	case p1Ptr.Interface.Name == defaultIfName:
		return sortReceiverBeforeArg
	case p2Ptr.Interface.Name == defaultIfName:
		return sortArgBeforeReceiver
	default:
		return sortDeferDecision
	}
}
func AscIfName(p1Ptr, p2Ptr *IfAddr) int {
	return strings.Compare(p1Ptr.Name, p2Ptr.Name)
}