Bash Cookbook is for power users or system administrators who are involved in writing Bash scripts in order to automate tasks or are aiming to enhance their productivity on the command line. For example, instead of remembering a series of commands to perform a specific operation, all of those commands can be put into a single script dedicated to that task, and they can perform input validation and format output. Why not save time and reduce errors through a powerful tool?

This book is also ideal if you are interested in learning how to automate complex daily system tasks that can be executed by various system infrastructure such as starting a script on system boot, or through scheduled cron jobs.

Chapter 1, Crash Course in Bash, covers the Linux shell/Bash to get you up and running, and the remainder of the book will just fall into place.

Chapter 2, Acting Like a Typewriter and File Explorer, introduces several bolt-on technologies to make Bash even more extensive when searching for items and text, or automating file explorer/filesystem operations. 

Chapter 3, Understanding and Gaining File System Mastery, will help you view files from various angles: head, tail, less, searching for files by name and/or extension, creating a diff of two files, patching, creating symbolic links and using them effectively, crawling filesystem directories, printing a tree, and more.

Chapter 4, Making a Script Behave Like a Daemon, is about creating components that mimic application functionality, such as menus or a daemon.

Chapter 5, Scripts for System Administration Tasks, introduces logs, archiving them, job/task management, network connectivity, securing systems using a firewall (iptables), monitoring directories for changes, and creating users.

Chapter 6, Scripts for Power Users, is about creating syslog entries using the logger command, taking backups, creating graphics and presentations on the CLI, checking file integrity and tampering, mounting network filesystems, retrieving files, browsing the Web, capturing network traffic, finding binary dependencies, and encrypting and decrypting a file.

Chapter 7, Writing Bash to Win and Profit, will help you learn how to use commands and scripts for many tasks. You will get an idea about writing bash scripts for monitoring certain tasks. 

Chapter 8, Advanced Scripting Techniques, will help you learn about advanced scripting techniques as well as how to customize their shell.

As the authors, we wrote this book to be accessible and teach you, the reader many different approaches to programming with Bash through several recipes. However, to get the most out of them, we encourage you to:

However,  this book assumes a certain level of knowledge to begin your journey and these skills will not be covered in this book. These skills include the following:

To gain proficiency in those areas, we recommend that you either give it your best shot if you are an adept problem solver and quick learner, or checkout the following resources first:

#!/bin/bash
AGE=17
if [ ${AGE} -lt 18 ]; then
    echo "You must be 18 or older to see this movie"
fi

rbrash@moon:~$ history
1002 ls
1003 cd ../
1004 pwd
1005 whoami
1006 history

In this book, you will find several headings that appear frequently (Getting ready, How to do it..., How it works..., There's more..., and See also).

To give clear instructions on how to complete a recipe, use these sections as follows:

Feedback from our readers is always welcome.

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