Interrupt a sleeping goroutine?

Question

Is there a way in which I can execute, for example

time.Sleep(time.Second * 5000) //basically a long period of time

and then "wake up" the sleeping goroutine when I wish to do so?

I saw that there is a Reset(d Duration) in Sleep.go but I'm unable to invoke it.. Any thoughts?

Answer 1

There isn't a way to interrupt a time.Sleep, however, you can make use of time.After, and a select statement to get the functionality you're after.

Simple example to show the basic idea:

package main

import (
    "fmt"
    "time"
)

func main() {
    timeoutchan := make(chan bool)

    go func() {
        <-time.After(2 * time.Second)
        timeoutchan <- true
    }()

    select {
    case <-timeoutchan:
        break
    case <-time.After(10 * time.Second):
        break
    }

    fmt.Println("Hello, playground")
}

http://play.golang.org/p/7uKfItZbKG

In this example, we're spawning a signalling goroutine to tell main to stop pausing. The main is waiting and listening on two channels, timeoutchan (our signal) and the channel returned by time.After. When it receives on either of these channels, it will break out of the select and continue execution.