package main

import (
	"io"
	"log"
	"os"
	"os/exec"

	"github.com/kr/pty"
)

func main() {
	cmd := exec.Command("snappy", "login", "potato")
	f, err := pty.Start(cmd)
	if err != nil {
		log.Fatal(err)
	}

	buf := make([]byte, 80)

	if n, err := f.Read(buf); err != nil {
		log.Fatal(err)
	} else {
		buf = buf[:n]
	}

	if string(buf) != "Password: " {
		log.Fatalf("got unexpected prompt: %q", string(buf))
	}

	if _, err := f.Write([]byte("swordfish\n")); err != nil {
		log.Fatal(err)
	}

	io.Copy(os.Stdout, f)
}