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36 lines
1005 B
Go
36 lines
1005 B
Go
package main
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/**
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In a particularly sensitive portion of code, you need to lock certain resources. Given
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the frequent use of channels in your code, you’d like to do this with channels instead
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of the sync package.
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When talking about using a channel as a lock, you want this kind of behavior:
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1 A function acquires a lock by sending a message on a channel.
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2 The function proceeds to do its sensitive operations.
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3 The function releases the lock by reading the message back off the channel.
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4 Any function that tries to acquire the lock before it’s been released will pause
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when it tries to acquire the (already locked) lock.
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**/
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import (
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"fmt"
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"time"
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)
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func main() {
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lock := make(chan bool, 2)
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for i := 1; i < 7; i++ {
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go worker(i, lock)
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}
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time.Sleep(time.Second * 10)
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}
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func worker(id int, lock chan bool) {
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fmt.Printf("%d wants the lock\n", id)
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lock <- true
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fmt.Printf("%d has the lock\n", id)
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time.Sleep(500 * time.Millisecond)
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fmt.Printf("%d is releasing the lock\n", id)
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<-lock
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}
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