gistfile1.txt

package main

import "fmt"

func main() {
	chans := make([]chan int, 4)
	for i := range chans {
		chans[i] = make(chan int, 0)
	}

	go client(1, chans[0], 2)
	go client(2, chans[1], 3)
	go client(3, chans[2], 5)
	go client(4, chans[3], 1)

	n := 100
	for {
		for i := range chans {
			sendit(chans, i, n)
		}
		n++
	}
}

func sendit(chans []chan int, i int, n int) {
	defer func() {
		if r := recover(); r != nil {
			fmt.Printf("PARENT: chans[%d] closed; nullifying.\n", i)
			chans[i] = nil
		}
	}()
	if chans[i] != nil {
		fmt.Printf("PARENT: sending message to chans[%d]\n", i)
		chans[i] <- n
	}
}

func client(id int, ch chan int, max int) {
	for i := 0; i < max; i++ {
		msg := <-ch
		fmt.Printf("CHILD %d: received message %d/%d: (%d)\n", id, i+1, max, msg)
	}
	fmt.Printf("CHILD %d: shutting down.\n", id)
	close(ch)
}