Golang synchronization

Synchronization tools are used to synchronize multiple concurrent codepaths so that your program can continue synchronously.

WaitGroups

WaitGroups are global threadsafe counters that are incremented/decremented.

wg = sync.WaitGroup{}

wg.Add(3)  // add 3x increments to countdown
wg.Done()  // decrement waitgroup by one
wg.Wait()  // wait for waitgroup to reach 0

// wait-groups are threadsafe proxy objects, intended to be globally accessible
var wg = sync.WaitGroup{}

func printHi() {
    fmt.Println("hi")
    wg.Done()
}

func main() {
    wg.Add(3)
    for i=0; i<3; i++ {
        go printHi()
    }
    wg.Wait()
    fmt.Println("bye")
}