Goroutine creation - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a goroutine in Go?

A goroutine is a lightweight thread managed by the Go runtime. It allows functions to run concurrently without the overhead of traditional threads.

beginner

How do you start a new goroutine?

Use the keyword go before a function call. For example: go myFunction() starts myFunction as a new goroutine.

intermediate

What happens if the main function finishes before goroutines complete?

The program exits immediately, and any running goroutines are stopped. You need to synchronize or wait for goroutines to finish to see their output.

intermediate

Can goroutines share memory? How should they communicate?

Goroutines can share memory, but it is safer to communicate using channels to avoid race conditions and ensure safe data exchange.

beginner

Write a simple example to create a goroutine that prints "Hello from goroutine!".

```go
package main
import (
  "fmt"
  "time"
)
func main() {
  go func() {
    fmt.Println("Hello from goroutine!")
  }()
  time.Sleep(100 * time.Millisecond) // Wait to let goroutine finish
}
```

Which keyword starts a new goroutine in Go?

A async

B go

C thread

D spawn

The go keyword is used to start a new goroutine.

What happens if the main function ends before goroutines finish?

A Program exits immediately, stopping goroutines

B Program waits for all goroutines automatically

C Goroutines continue running in background

D Compiler throws an error

The program exits immediately, stopping all running goroutines.

Which is the safest way for goroutines to communicate?

A Using files

B Global variables without locks

C Printing to console

D Channels

Channels provide safe communication between goroutines avoiding race conditions.

What is a goroutine best described as?

A A lightweight thread managed by Go runtime

B A heavyweight OS thread

C A function that runs only once

D A type of variable

Goroutines are lightweight threads managed by the Go runtime.

How do you ensure a goroutine has time to finish before main exits?

A Call <code>exit()</code> after goroutine

B Nothing, it finishes automatically

C Use time.Sleep or synchronization methods

D Use the <code>wait</code> keyword

You can use time.Sleep or synchronization tools like WaitGroups to wait for goroutines.

Explain how to create and run a goroutine in Go and why it is useful.

Think about how Go lets you run tasks at the same time easily.

Describe what happens if the main function finishes before goroutines complete and how to handle it.

Consider the program lifecycle and waiting for tasks.