bash.md

Bash Script Debugging Cheatsheet

⚠️ If you are finding that you would like deeper debugging with a bash script, consider using another platform (like Python) to do what your shell script is intending ⚠️

Expanding commands

This is the biggest help when trying to figure out what or why a bash script is doing what it is doing. This trick will allow you to see all command expansions and dump them to stdout (effectively taking any guesswork out)

In a script

Add set -x before you want to start expanding all commands

(optionally) add set +x to not expand commands that follow

From the terminal

Run your script with -x: $ bash -x <script>

Stop script on a non-zero exit code

If you want to stop executing your script when a command returns a non-zero exit code, this is an effective way to see what is failing

In a script

Add set -e when you want this behavior to take effect

From the terminal

Run your script with -e: $ bash -e <script>