close.go

package main

import (
	"fmt"
	"sync"
	"time"
)

var quitLock sync.RWMutex

func main() {
	quit := false

	timeUp := time.After(10 * time.Second)
	done := make(chan bool)
	intQ := make(chan int, 20)

	go func() {
		for i := 0; i < 1000; i++ {
			intQ <- i
			quitLock.RLock()
			if quit {
				quitLock.RUnlock()
				done <- true
				break
			}
			quitLock.RUnlock()
		}
	}()

	go func() {
		for {
			fmt.Println(<-intQ)
			time.Sleep(100 * time.Millisecond)
		}
	}()

	<-timeUp

	quitLock.Lock()
	quit = true
	quitLock.Unlock()

	<-done

	fmt.Println("closing")
	close(intQ)
	fmt.Println("closed")

	go func() {
		for {
			fmt.Println(<-intQ)
			time.Sleep(1 * time.Second)
		}
	}()

	time.Sleep(10 * time.Second)
}