Mastering Linux Shell Scripting: A practical guide to Linux command-line, Bash scripting, and Shell programming, 2nd Edition

Master the complexities of Bash shell scripting and unlock the power of shell for your enterprise

• Identify high-level steps such as verifying user input
• Using the command line and conditional statements in creating/executing simple shell scripts
• Create and edit dynamic shell scripts to manage complex and repetitive tasks
• Leverage the command-line to bypass GUI and automate common tasks

In this book, you'll discover everything you need to know to master shell scripting and make informed choices about the elements you employ.

Grab your favorite editor and start writing your best Bash scripts step by step. Get to grips with the fundamentals of creating and running a script in normal mode, and in debug mode. Learn about various conditional statements' code snippets, and realize the power of repetition and loops in your shell script. You will also learn to write complex shell scripts. This book will also deep dive into file system administration, directories, and system administration like networking, process management, user authentications, and package installation and regular expressions. Towards the end of the book, you will learn how to use Python as a BASH Scripting alternative.

By the end of this book, you will know shell scripts at the snap of your fingers and will be able to automate and communicate with your system with keyboard expressions.

• Make, execute, and debug your first Bash script
• Create interactive scripts that prompt for user input
• Foster menu structures for operators with little command-line experience
• Develop scripts that dynamically edit web configuration files to produce a new virtual host
• Write scripts that use AWK to search and reports on log files
• Draft effective scripts using functions as building blocks, reducing maintenance and build time
• Make informed choices by comparing different script languages such as Python with BASH

If you are a Linux administrator or a system administrator and are interested in automating tasks in your daily lives, saving time and effort, this book is for you. Basic shell scripting and command-line experience will be required. Familiarity with the tasks you need to automate will be helpful.

1. What and Why of Scripting with BASH
2. Creating Interactive Scripts
3. Conditions attached
4. Creating Code Snippets
5. Alternative syntax
6. Iterating with Loops
7. Creating Building Blocks with Functions
8. Introducing sed
9. Automating Apache Virtual Hosts
10. AWK Fundamentals
11. Regular expressions
12. Summarizing Logs with awk
13. A Better lastlog with Awk
14. Using Python as a BASH Scripting Alternative