outbound can't get event in real-time

[transtone]

when ReadEvent in outbound, it can't get the events in real-time, all events will send on just disconnect when use linger.
if not use linger, it can't get any event at all.

// Copyright 2013 Alexandre Fiori
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Server that accepts connections from FreeSWITCH and controls incoming calls.
package main

import (
	"fmt"
	"log"

	"github.com/fiorix/go-eventsocket/eventsocket"
)

// const audioFile = "/opt/freeswitch/sounds/en/us/callie/misc/8000/sorry.wav"
const audioFile = "/usr/share/freeswitch/sounds/music/8000/partita-no-3-in-e-major-bwv-1006-1-preludio.wav"

func main() {
	eventsocket.ListenAndServe(":9090", handler)
}

func handler(c *eventsocket.Connection) {
	fmt.Println("new client:", c.RemoteAddr())
	c.Send("connect")
	c.Send("myevents")
	c.Send("event plain ALL")
	c.Send("start_dtmf")
        c.Send("linger")
	c.Execute("answer", "", false)
	c.Execute("playback", audioFile, true)
	
	for {
		ev, err := c.ReadEvent()
		if err != nil {
			log.Fatal(err)
		}
		fmt.Println("\nNew event")
		ev.PrettyPrint()
		if ev.Get("Application") == "playback" {
			if ev.Get("Application-Response") == "FILE PLAYED" {
				c.Send("exit")
			}
		}
	}
}