Two implementations of syncing all goroutines in go -> using waitgroups and channels.

!concurrency

This gist shows two examples of how to make all goroutines finish in a Go program. There are two implementations mentioned here:

1. Using channels
2. Using goroutines

channels.go

// using channels to sync all goroutines
package main

import "fmt"
import "time"

func main() {
    list := []string{
        "1",
        "2",
        "3",
        "4",
        "5",
    }

    ch := make(chan string, len(list))

    for _, v := range list {
        go func(v string) {
            time.Sleep(time.Second)
            ch <- v
        }(v)
    }

    // waiting for all goroutines to finish
    for i := 0; i < len(list); i ++ {
        fmt.Println(<- ch)
    }

}

waitgroups.go

// using waitgroups to sync all goroutines
package main

import "fmt"
import "time"
import "sync"

func main() {
    list := []string{
        "1",
        "2",
        "3",
        "4",
        "5",
    }

    wg := sync.WaitGroup{}
    wg.Add(len(list))

    for _, v := range list {
        go func(v string) {
            time.Sleep(time.Second)
        	fmt.Println(v)
            wg.Done()
        }(v)
    }

    // waiting for all goroutines to finish
    wg.Wait()

}