You're reading from The Ultimate Linux Shell Scripting Guide Automate, Optimize, and Empower tasks with Linux Shell Scripting

Product type Paperback

Published in Oct 2024

Publisher Packt

ISBN-13 9781835463574

Length 696 pages

Edition 1st Edition

Languages

Bash

Tools

Linux

Concepts

Cybersecurity

Author (1):

Donald A. Tevault

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Table of Contents (26) Chapters

Preface

1. Getting Started with the Shell FREE CHAPTER

2. Interpreting Commands

3. Understanding Variables and Pipelines

4. Understanding Input/Output Redirection

5. Customizing the Environment

6. Text-Stream Filters – Part 1

7. Text Stream Filters – Part 2

8. Basic Shell Script Construction

9. Filtering Text with grep, sed, and Regular Expressions

10. Understanding Functions

11. Performing Mathematical Operations

12. Automating Scripts with here Documents and expect

13. Scripting with ImageMagick

14. Using awk – Part 1

15. Using awk – Part 2

16. Creating User Interfaces with yad, dialog, and xdialog

17. Using Shell Script Options with getops

18. Shell Scripting for Security Professionals

19. Shell Script Portability

20. Shell Script Security

21. Debugging Shell Scripts

22. Introduction to Z Shell Scripting

23. Using PowerShell on Linux

24. Other Books You May Enjoy

25. Index

Understanding POSIX compliance

Way back in the Stone Age of Computing, there was no such thing as standardization. In order to keep things relevant, let’s begin our history with the advent of Unix.

AT&T, who created Unix in the early 1970s, wasn’t allowed to market it until 1983. This was due to an anti-trust legal case that the U.S. government had filed against AT&T back in 1956. (I don’t know the details of the case, so please don’t ask.) But, they were allowed to license the code to other vendors so that they could sell their own modified implementations. Because of this, several different implementations of Unix emerged, which weren’t always completely compatible with each other. These different implementations included the Berkeley Software Distribution (BSD), Microsoft Xenix, and SunOS. In 1983, AT&T was finally allowed to market its own System V Unix. Making things more interesting was the wide variety of shells that eventually...