Install ShellCheck on Ubuntu 24.04

ShellCheck is a static analysis tool designed for shell scripts. It helps identify common issues, errors, and potential bugs in scripts written in shell scripting languages such as Bash. ShellCheck analyzes the script and provides warnings or suggestions for improvement, making it easier to write clean, reliable, and maintainable shell scripts. This tutorial explains how to install ShellCheck on Ubuntu 24.04.

Install ShellCheck

Check the latest ShellCheck version from its GitHub repository and store it in a variable:

SHELLCHECK_VERSION=$(curl -s "https://api.github.com/repos/koalaman/shellcheck/releases/latest" | grep -Po '"tag_name": "v\K[0-9.]+')

Utilize the previously identified version to download the ShellCheck archive:

wget -qO shellcheck.tar.xz https://github.com/koalaman/shellcheck/releases/latest/download/shellcheck-v$SHELLCHECK_VERSION.linux.x86_64.tar.xz

Create temporary directory and extract a tar.xz file:

mkdir shellcheck-temp

tar xf shellcheck.tar.xz --strip-components=1 -C shellcheck-temp

Move executable to /usr/local/bin directory:

sudo mv shellcheck-temp/shellcheck /usr/local/bin

To determine the ShellCheck version, run this command:

shellcheck --version

Delete the unnecessary archive and directory:

rm -rf shellcheck.tar.xz shellcheck-temp

Testing ShellCheck

Create Bash script for testing purposes:

nano test.sh

Add the following code:

#!/bin/bash

test="Hello world"
echo $test

To use ShellCheck, run the shellcheck command followed by the Bash script's name:

shellcheck test.sh

It will analyze the script and provide feedback, such as warning about unquoted variables, with suggestions on how to fix the issue and links to further information:

In test.sh line 4:
echo $test
     ^---^ SC2086 (info): Double quote to prevent globbing and word splitting.

Did you mean: 
echo "$test"

For more information:
  https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...

Uninstall ShellCheck

To remove ShellCheck, delete its corresponding file:

sudo rm -rf /usr/local/bin/shellcheck