Goroutines

A goroutine is a lightweight thread managed by the Go runtime: go f(x, y, z) starts a new running goroutine f(x, y, z). The evaluation of f, x, y, and z happens in the current goroutine and the execution of f happens in the new goroutine.

Goroutines run in the same address space, so access to shared memory must be synchronized. The sync package provides useful primitives, but there are other primitives to be used more commonly. (introduced later)

Example

package main

import (
	"fmt"
	"time"
)

func print(s string) {
	for i := 0; i < 5; i++ {
		time.Sleep(100 * time.Millisecond)
		fmt.Println(s)
	}
}

func main() {
	go print("Oliver")
	print("Hello!")
}

Hello!
Oliver
Oliver
Hello!
Hello!
Oliver
Oliver
Hello!
Hello!