GO語言練習：channel select 逾時機制

這是一個建立於 的文章，其中的資訊可能已經有所發展或是發生改變。

1、代碼

2、運行

3、解析

 

1、代碼

 1 package main 2  3 import ( 4     "time" 5     "fmt" 6 ) 7  8 func waitFor(ch chan int) { 9     fmt.Println(time.Now(), "writing ...")10     time.Sleep(1e9)11     ch <- 1012     fmt.Println(time.Now(), "wrote ...")13 }14 15 func main() {16     var a chan int = make(chan int)17     var b chan int = make(chan int)18     var ch chan int = make(chan int)19 20     go waitFor(ch)21 22     var r int = 023     fmt.Println(time.Now(), "select ...")24     select {25     case x := <-a :26         fmt.Println(time.Now(), "read from a...")27         r = x28     case x := <-b :29         fmt.Println(time.Now(), "read from b...")30         r = x31     case x := <-ch :32         fmt.Println(time.Now(), "read from ch...")33         r = x34     }35     fmt.Println(time.Now(), "select over.., r = ", r)36     time.Sleep(1e9)37     fmt.Println(time.Now(), "over..")38 }

2、運行

1 $ go run timeout.go 2 2015-07-19 00:35:23.859684465 +0800 CST select ...3 2015-07-19 00:35:23.861022451 +0800 CST writing ...4 2015-07-19 00:35:24.864462549 +0800 CST wrote ...5 2015-07-19 00:35:24.865185396 +0800 CST read from ch...6 2015-07-19 00:35:24.874655353 +0800 CST select over.., r =  107 2015-07-19 00:35:25.888486739 +0800 CST over..

3、解析

　　1）主線程中的select開始運行，對select中的3個channel進行阻塞等待

　　2）線上程（協程）waitFor中向ch寫入資料

　　3）select收到資料，進行讀取

　　4）主線程退出