[Go] Using goroutine.

package main

import (
    "log"
    "os"
    "sync"
)

func main() {
    // A goroutine-safe console printer.
    logger := log.New(os.Stdout, "", 0)

    // Sync between goroutines.
    var wg sync.WaitGroup

    // Add goroutine 1.
    wg.Add(1)
    go func() {
        defer wg.Done()
        logger.Println("Print from goroutine 1")
    }()

    // Add goroutine 2.
    wg.Add(1)
    go func() {
        defer wg.Done()
        logger.Println("Print from goroutine 2")
    }()

    // Add goroutine 3.
    wg.Add(1)
    go func() {
        defer wg.Done()
        logger.Println("Print from goroutine 3")
    }()

    logger.Println("Print from main")

    // Wait all goroutines.
    wg.Wait()
}