Book Image

Mastering Linux Shell Scripting - Second Edition

By : Mokhtar Ebrahim, Andrew Mallett
5 (1)
Book Image

Mastering Linux Shell Scripting - Second Edition

5 (1)
By: Mokhtar Ebrahim, Andrew Mallett

Overview of this book

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.
Table of Contents (17 chapters)

Summarizing Logs with AWK

In the previous chapter, we talked about regular expressions and we saw how to use them to empower sed and AWK. In this chapter, we will discuss some practical examples of using AWK.

One of the tasks that AWK is really good at is filtering data from log files. These log files may be many lines in length, perhaps 250,000 or more. I have worked with data with over a million lines. AWK can process these lines quickly and effectively. As an example, we will work with a web server access log with 30,000 lines to show how effective and well-written AWK code can be. As we work our way through the chapter, we will also see different log files and review some of the techniques that we can employ with the awk command and the AWK programming language to help with the reporting and administration of our services. In this chapter, we will cover the following topics...