dialvia.go

package main

import (
	"log"
	"net"
	"time"
)

func perr(err error) {
	if err != nil {
		panic(err)
	}
}

func main() {
	ifaces, err := net.Interfaces()
	perr(err)
	for _, iface := range ifaces {
		log.Println("INTERFACE", iface)
		addrs, err := iface.Addrs()
		perr(err)
		for _, addr := range addrs {
			log.Println("ADDR", addr)
			if addr, ok := addrs[0].(*net.IPNet); ok {
				log.Println("OK net.IPNet")
				tcpAddr := &net.TCPAddr{
					IP: addr.IP,
				}
				d := net.Dialer{
					Timeout:   3 * time.Second,
					LocalAddr: tcpAddr,
				}
				_, err = d.Dial("tcp", "google.com:80")
				if err != nil {
					log.Println("ERROR", err)
				} else {
					log.Println(">>> WOOHOO")
				}
			} else {
				log.Println("NOT net.IPNet")
			}
		}
	}
}