Book Image

Linux Shell Scripting Bootcamp

By : James K Lewis
Book Image

Linux Shell Scripting Bootcamp

By: James K Lewis

Overview of this book

Linux Shell Scripting Bootcamp is all about learning the essentials of script creation, validating parameters, and checking for the existence of files and other items needed by the script. We will use scripts to explore iterative operations using loops and learn different types of loop statements, with their differences. Along with this, we will also create a numbered backup script for backup files. Further, you will get well-versed with how variables work on a Linux system and how they relate to scripts. You’ll also learn how to create and call subroutines in a script and create interactive scripts. The most important archive commands, zip and tar, are also discussed for performing backups. Later, you will dive deeper by understanding the use of wget and curl scripts and the use of checksum and file encryption in further chapters. Finally, you will learn how to debug scripts and scripting best practices that will enable you to write a great code every time! By the end of the book, you will be able to write shell scripts that can dig data from the web and process it efficiently.
Table of Contents (19 chapters)
Linux Shell Scripting Bootcamp
Credits
About the Author
Acknowledgement
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Index

Chapter 9. Debugging Scripts

This chapter shows how to debug Bash shell scripts.

Programming in any language, be it C, Java, FORTRAN, COBOL*, or Bash can be a lot of fun. However, what is often not fun is when something goes wrong, and when it takes an inordinate amount of time to find the problem and then solve it. This chapter will attempt to show the reader how to avoid some of the more common syntax and logic errors, and also how to find them when they occur.

*COBOL: Okay, I have to say that programming in COBOL was never fun!

The topics covered are in the chapter are:

  • How to prevent some common syntax and logic errors.

  • The shell debugging commands such as set -x and set -v.

  • The other ways to set up debugging.

  • How redirection can be used to debug in real time.