dontblockonlisten.go

package main

import (
	"log"
	"time"
)

func main() {
	nobodyListening := make(chan struct{})

	go func(sendMsg chan<- struct{}) {
		time.Sleep(time.Second * 3)
		sendMsg <- struct{}{}
	}(nobodyListening)

	for i := 0; i < 5; i++ {
		select {
		case <-nobodyListening:
			log.Printf("Got a message")
		default:
			log.Printf("Nobody's listening!")
		}
		<-time.Tick(time.Second * 1)

	}
}