Linux — Shell Scripting/Functions

The purpose of this hands-on training is to teach you how to use functions in shell.

Learning Outcomes

At the end of this hands-on training, you will be able to;

• explain and use functions in the shell.

Outline

• Part 1 — Creating Functions
• Part 2 — Passing Arguments to Functions
• Part 3 — Returning Values from Functions
• Part 4 — Nested Functions
• Part 5 — Variables Scope

Part 1 — Creating Functions

• A Bash function is a piece of code that only runs when it is called. Functions enable you to reuse code. We can call the functions numerous times.
• Create a folder and name it functions.

mkdir functions && cd functions

• It is pretty easy to declare and call a function. Create a script file named functions.sh.

#!/bin/bash

Welcome () {
    echo "Welcome to Linux Lessons"
}
Welcome

• Make the script executable and execute it.

chmod +x functions.sh
./functions.sh

Part 2 — Passing…