Linux Fundamentals - Part 8: Bash Scripting (Functions)

Bash Function

A function is a block of code that performs a specific task.

Instead of writing the same commands over and over, you can put them inside a function and call it whenever you need.

Think of a function as a mini-program inside your script.

How to Define a Function?

The basic syntax of a Bash function looks like this:

my_function() {

  commands…

}

The name goes first, followed by (), then the body of the function inside {}.

Example:

#!/bin/bash



hello() {

  echo "Hello from a function!"

}

This defines a function called hello. It doesn’t do anything until you call it.

Calling (Using) a Function

To run a function, just write its name:

#!/bin/bash



hello() {

  echo "Hello from a function!"

}



hello

If you save this as func.sh and run:

bash func.sh 



or



./func.sh

The Output is:

Hello from a function!