如何等待一个以上的goroutine完成？

Question

package main

var fooRunning = false
var barRunning = false

func foo() {
    fooRunning = true
    defer func() { fooRunning = false }()
    if barRunning {
        // wait for bar() to finish
    }
    ...
}

func bar() {
    barRunning = true
    defer func() { barRunning = false }()
    if fooRunning {
        // wait for foo() to finish
    }
    ...
}

In my case if we run go foo() it should wait for bar() to finish and vice versa. What is the best way to do it? Note that they also can be executed independently.

Answer 1

You can use a channel! As i remember from my rusty go, this would give:

func foo() {
    c := make(chan int)
    go bar(c)
    <-c
}

and in bar

func bar(c chan int) {
    // do stuff here
    c <- 0
}