In this final chapter, we'll look at some techniques for programming in Bash defensively, safely, and productively, in a way that makes working with shell scripts a joy rather than a chore, especially by avoiding some nasty pitfalls in the language.

We'll revisit the following material from earlier chapters in more depth:

• Quoting correctly
• Handling filenames starting with dashes
• Separating output and diagnostics

We'll also cover:

• Keeping scripts brief and simple
• Keeping scripts flexible
• Respecting and applying the user's configuration
• Allowing scripts to run without user input
• Limiting the scope of shell state changes
• Avoiding path anti-patterns
• Avoiding Bash for untrusted user input
• Documenting scripts
• Using temporary files cleanly
• Cleaning up after a script
• A tool to check shell scripts for problems