Book Image

Mastering Linux Shell Scripting

By : Andrew Mallett
Book Image

Mastering Linux Shell Scripting

By: Andrew Mallett

Overview of this book

Shell scripting is a quick method to prototype a complex application or a problem by automating tasks when working on Linux-based systems. Using both simple one-line commands and command sequences complex problems can be solved with ease, from text processing to backing up sysadmin tools. In this book, you’ll discover everything you need to know to master shell scripting and make informed choices about the elements you employ. 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. Implement functions and edit files using the Stream Editor, script in Perl, program in Python – as well as complete coverage of other scripting languages to ensure you can choose the best tool for your project.
Table of Contents (21 chapters)
Mastering Linux Shell Scripting
About the Author
About the Reviewer

Chapter 9. Automating Apache Virtual Hosts

Now that we have seen a little of the stream editor, sed, we can put this knowledge into practice. In Chapter 8, Introducing sed, we became used to some of the capabilities of sed; however, this represents just a small amount of the power enclosed in the editor. In this chapter, we are going to exercise sed a little more and expose ourselves to some practical uses of the tool, especially when using our bash scripts.

In this journey, we will use sed to help us automate the creation of Apache name-based Virtual Hosts. The Apache hosts are practical users of sed that we demonstrated but more importantly, we will use sed to search for selected lines in the main configuration. We will then uncomment those lines and save them as a template. Having created the template, we will create new configurations from it. The concept that we demonstrate with Apache can be applied in many different situations.

We will find that using sed in our shell scripts will allow...