Go信號實例

有時我們希望Go程序能夠智能地處理Unix信號。 例如,可能希望服務器在接收到SIGTERM時正常關閉,或者在收到SIGINT時使用命令行工具停止處理輸入。下面介紹如何使用Go語言處理信號。

Go信號通知通過在通道上發送os.Signal值來工作。創建一個通道來接收這些通知(還會在程序退出時通知我們)。

所有的示例代碼,都放在 F:\worksp\golang 目錄下。安裝Go編程環境請參考:http://www.yiibai.com/go/go\_environment.html

signal.go的完整代碼如下所示 -

package main

import "fmt"
import "os"
import "os/signal"
import "syscall"

func main() {

    // Go signal notification works by sending `os.Signal`
    // values on a channel. We'll create a channel to
    // receive these notifications (we'll also make one to
    // notify us when the program can exit).
    sigs := make(chan os.Signal, 1)
    done := make(chan bool, 1)

    // `signal.Notify` registers the given channel to
    // receive notifications of the specified signals.
    signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)

    // This goroutine executes a blocking receive for
    // signals. When it gets one it'll print it out
    // and then notify the program that it can finish.
    go func() {
        sig := <-sigs
        fmt.Println()
        fmt.Println(sig)
        done <- true
    }()

    // The program will wait here until it gets the
    // expected signal (as indicated by the goroutine
    // above sending a value on `done`) and then exit.
    fmt.Println("awaiting signal")
    <-done
    fmt.Println("exiting")
}

執行上面代碼,將得到以下輸出結果 -

F:\worksp\golang>go run signal.go
awaiting signal
[Ctl+C]
interrupt
exiting