Go Signals

package main

import (
    "fmt"
    "os"
    "os/signal"
    "syscall"
)

func main() {

    sigs := make(chan os.Signal, 1)

    signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)

    done := make(chan bool, 1)

    go func() {

        sig := <-sigs
        fmt.Println()
        fmt.Println(sig)
        done <- true
    }()

    fmt.Println("awaiting signal")
    <-done
    fmt.Println("exiting")
}

package main

import (
    "fmt"
    "os"
    "os/signal"
    "syscall"
    "time"
)

func main() {

    osSignalChannel := make(chan os.Signal, 1)

    signal.Notify(osSignalChannel, syscall.SIGINT, syscall.SIGTERM)

    msgChannel := make(chan string)

    go func() {

        for {
            //wait on a message from a channel
            select {
            case signal := <-osSignalChannel:
                fmt.Println(signal)

                //call shutdown
                msgChannel <- "shutdown"

            case msg := <-msgChannel:
                fmt.Println("s: Received message:", msg)
                if msg == "shutdown" {
                    fmt.Println("s: Cleaning up")

                    //sleep
                    time.Sleep(time.Second * 30)

                    fmt.Println()
                    fmt.Println("s: Shutting down")

                    //notify shutdown
                    msgChannel <- "shutdown"

                    return

                } else {
                    fmt.Println("s: Received message:", msg, " ignoring...")
                }

            }
        }

    }()

    time.Sleep(time.Second * 1)

    //sens bogus message
    fmt.Println("m: Sending bogus message")
    msgChannel <- "bogus"

    time.Sleep(time.Second * 5)

    //send shutdown
    fmt.Println("m: Sending shutdown message")
    msgChannel <- "shutdown"

    fmt.Println("m: Waiting for response message")
    response := <-msgChannel
    fmt.Println("m: Response: ", response)
    fmt.Println("m: Exiting")
}

package main
import (
	"fmt"
	"os"
	"os/signal"
	"syscall"
	"time"
)

func main() {
	
	//create channel that can receive OS signals
	ch := make(chan os.Signal)

    //Submit channel to the notify signal
	signal.Notify(ch, syscall.SIGTERM, syscall.SIGINT)


	//a go function to monitor signals in the background
	go func() {
		for sig := range ch {
			switch sig {
			case syscall.SIGTERM:
				fmt.Println("sigterm received')
				os.Exit(0)
			case syscall.SIGINT:
				fmt.Println("sigint received')
				oS.Exit(0)
			}
		}
	}()

	time.Sleep(time.Minute)
}