golang

channels.go

package main

import "fmt"

func main() {
	ch := make(chan int)
	go fibs(ch)
	for i := 0; i < 20; i++ {
		fmt.Println(<-ch)
	}
	ch <- 0
}

func fibs(ch chan int) {
	i, j := 0, 1
	for {
		select {
		case ch <- j:
			i, j = j, i+j
		case <- ch :
			return
		}
	}
}

signal.go

c := make(chan os.Signal, 1)
signal.Notify(c, os.Interrupt)
go func() {
	<-c
	log.Print("deleting database db")
	os.RemoveAll("db")
	defer os.RemoveAll("db")
	os.Exit(1)
}()