GoLang - Routine

6 minute read

Welcome to the world of Go programming! In this short inception, we’ll dive into the fascinating concept of routines in Go. Routines, also known as goroutines, are lightweight threads of execution that allow you to perform tasks concurrently. Unlike traditional threads, routines in Go are efficient and can be created in large numbers without significant overhead.

By using routines, you can make your programs more responsive and take advantage of the inherent concurrency capabilities of the Go language. With just a few simple steps, you can harness the power of routines and unlock the potential of concurrent programming.

In this tutorial, we’ll explore the basics of routines in Go programming. You’ll learn how to create routines, wait for their completion, and pass data to them. We’ll provide you with clear examples and explanations, all presented in simple language without any technical jargon.

You’ll discover how to create a routine in Go using the go keyword, enabling your functions to run concurrently. We’ll show you how to ensure that your program doesn’t terminate before all routines are finished using the sync package and the WaitGroup type.

Additionally, we’ll guide you through passing data to routines, both by directly passing values as function arguments and by using closures. You’ll gain a solid understanding of how to effectively communicate data to your concurrent tasks.

By the end of this tutorial, you’ll be equipped with the knowledge and tools to incorporate routines into your Go programs, enabling you to leverage the power of concurrency and parallelism. Whether you’re a beginner or have some experience in Go programming, this tutorial will help you grasp the fundamentals of routines in a straightforward manner.

So, let’s embark on this journey into the world of routines in Go programming and unlock the true potential of concurrent programming. Get ready to make your programs faster, more efficient, and responsive. Let’s dive in and explore the exciting realm of routines in Go!

In Go programming, routines play a vital role in concurrency and parallelism. A routine, also known as a goroutine, is a lightweight thread of execution that allows multiple tasks to run concurrently. This tutorial will walk you through the concept of routines in Go programming, their benefits, and how to use them effectively with examples. So let’s get started!

What is a Routine?

A routine in Go is a function that runs independently and concurrently with other routines. It allows you to perform tasks concurrently, making your programs more efficient and responsive. Unlike traditional threads, routines in Go are lightweight, meaning you can create thousands of them without significant performance overhead.

Creating a Routine

To create a routine in Go, you need to prefix the function call with the keyword 'go'. Here’s the syntax:

go functionName(arguments)

For example, let’s say we have a function called 'printMessage' that prints a message:

func printMessage(message string) {

To run this function as a routine, you would write:

go printMessage("Hello, Go!")

The 'printMessage' function will be executed concurrently in its own goroutine.

Wait for Routines to Complete: By default, the Go program terminates when the 'main' function completes. To wait for the routines to finish their execution before the program exits, you can use the 'sync' package and its 'WaitGroup' type. Here’s an example:

package main

import (

func printMessage(message string, wg *sync.WaitGroup) {
    defer wg.Done() // Signals that this routine is done


func main() {
    var wg sync.WaitGroup

    wg.Add(1) // Number of routines to wait for

    go printMessage("Hello, Go!", &wg)

    wg.Wait() // Waits until all routines are done

In this example, we create a 'WaitGroup' variable 'wg' to keep track of the number of routines we want to wait for. We increment the 'wg' counter using 'wg.Add(1)' before starting the routine. Within the routine, we call 'wg.Done()' to indicate that the routine has completed. Finally, we use 'wg.Wait()' in the 'main' function to wait until all routines are done.

Passing Data to Routines

To pass data to a routine, you can either pass the values directly as function arguments or use closures. Let’s see both approaches:

Passing values directly:

func printNumber(number int) {

func main() {
    go printNumber(42)

Using closures:

func main() {
    number := 42

    go func() {

In both cases, the value 42 is passed to the routine for printing.


Routines in Go programming allow you to execute tasks concurrently, enhancing the performance and responsiveness of your programs. In this tutorial, you learned how to create routines, wait for their completion, and pass data to them. By leveraging the power of routines, you can build highly efficient and scalable applications in Go. Keep exploring the Go language and its concurrency features to unlock its full potential!

Basic Interview Questions and Answers

The following are the top 10 common interview questions related to routines in Go programming, along with their answers in simple language and without plagiarism:

Question 1: What is a routine in Go programming?

Answer: A routine, also known as a goroutine, is a lightweight thread of execution in Go programming. It allows multiple tasks to run concurrently, enhancing the efficiency and responsiveness of programs.

Question 2: How do you create a routine in Go?

Answer: To create a routine in Go, you prefix the function call with the keyword 'go'. For example, 'go functionName(arguments)' will execute the 'functionName' concurrently as a routine.

Question 3: Why are routines important in Go programming?

Answer: Routines enable concurrent execution, making Go programs more efficient and scalable. They facilitate parallel processing, allowing tasks to run simultaneously and utilize available resources effectively.

Question 4: How do you wait for a routine to finish in Go?

Answer: To wait for a routine’s completion, you can use the 'sync' package and its 'WaitGroup' type. By incrementing the 'WaitGroup' counter before starting the routine and calling 'wg.Done()' within the routine, you can use 'wg.Wait()' in the 'main' function to wait until all routines are done.

Question 5: Can you explain how to pass data to a routine in Go?

Answer: Data can be passed to a routine by either directly passing values as function arguments or using closures. For example, you can pass values like 'go functionName(value)' or use a closure with 'go func() { // code using the value }()'.

Question 6: What are the benefits of using routines in Go programming?

Answer: Routines facilitate concurrent execution, enabling better utilization of system resources, improved performance, and responsiveness. They simplify handling multiple tasks and help build efficient and scalable applications.

Question 7: How do routines achieve concurrency in Go?

Answer: Routines achieve concurrency by utilizing goroutine scheduling, which allows the Go runtime to multiplex several goroutines on a small number of operating system threads. This lightweight approach enables efficient and concurrent execution.

Question 8: What is the difference between a routine and a traditional thread?

Answer: Routines in Go are lightweight compared to traditional threads. You can create thousands of routines without significant performance overhead. They provide a simpler concurrency model and are managed by the Go runtime.

Question 9: Can you give an example where using routines in Go is beneficial?

Answer: Consider a web server that needs to handle multiple client requests concurrently. By using routines, each incoming request can be processed independently, allowing the server to handle numerous requests simultaneously without blocking others.

Question 10: How do routines handle errors in Go?

Answer: Routines can return errors like regular functions. To handle errors from routines, you can use error values, channels for error communication, or the 'select' statement to handle multiple goroutines simultaneously and handle errors as they occur.

Remember, while preparing for interviews, it’s essential to understand the concepts and adapt the answers to your own experiences and knowledge.