To get the most out of this book

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:

• Have a Linux system setup and configured (ideally Ubuntu) to complete the recipes
• Work through the recipes 
• Keep in mind what the components of each recipe and even the recipes themselves to see how they could be reused or combined in new ways

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:

• How to setup and configure a Linux system
• How to install, access, and configure a specific text editor (although several are already included in most Linux distributions)
• Some basics about computing and programming (although we will do our best to provide a crash course)

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:

• Linux or distribution communities
• Open source forums or groups
• YouTube or similar media

Download the example code files

You can download the example code files for this book from your account at www.packtpub.com. If you purchased this book elsewhere, you can visit www.packtpub.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

1. Log in or register at www.packtpub.com.
2. Select the SUPPORT tab.
3. Click on Code Downloads & Errata.
4. Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

• WinRAR/7-Zip for Windows
• Zipeg/iZip/UnRarX for Mac
• 7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Bash-Cookbook. In case, there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The full path is more concrete and hardcoded; the interpreter will try to use the complete path. For example, /bin/ls or /usr/local/bin/myBinary.."

A block of code is set as follows:

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

Any command-line input or output is written as follows:

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

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this.

Warnings or important notes appear like this.

Tips and tricks appear like this.