38 lines
783 B
Go
38 lines
783 B
Go
// wait for multiple goroutines to finish
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package main
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import (
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"fmt"
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"sync"
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"time"
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)
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// function to run in every goroutine
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func worker(id int) {
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fmt.Printf("Worker %d starting\n", id)
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time.Sleep(time.Second)
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fmt.Printf("Worker %d done\n", id)
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}
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func main() {
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// WaitGroup is used to wait for all the goroutines launched here to finish
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var wg sync.WaitGroup
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// Launch several goroutines and increment the WaitGroup counter for each
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for i := 1; i <= 5; i++ {
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wg.Add(1)
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// Avoid re-use of the same i value in each goroutine closure
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i := i
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// Wrap the worker call in a closure that makes sure to tell the WaitGroup that this worker is done
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go func() {
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defer wg.Done()
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worker(i)
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}()
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}
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// Block until the WaitGroup counter goes back to 0
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wg.Wait()
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}
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