This is the third edition of the book and I’ve been well pleased with it. The first part of the book is dedicated to the command line and gaining familiarization with the various commands, file system, navigation, etc. The real meat of the book begins with part 2 where you actually start scripting.
As a software developer by trade, Linux scripting is something that I find myself naturally drawn to. All of the systems I utilize at work aside from my desktop run Red Hat Enterprise Linux so I spend a great deal of time in terminal sessions. Many of the things I do are extremely repetitive and while I can’t (due to security limitations) put custom scripts in every environment I’m slowly working on a library that can help be do those mundane tasks quickly and with reproducible results.
Part 3 covers advanced scripting and the use of tools like sed and awk. Both of these along with regular expressions play a big role in my daily work. I really can’t imagine how difficult it would be for me to evaluate logs and generate reports for executive management without tools like these to make the job significantly easier and faster. I can easily scan massive business logs for key errors and use awk to generate an extract of the critical information I need to review. sed is a great tool when I need to make wholesale changes to configuration files as an example.
Part 4 gets you creating more real-world scripts. You’ll learn how to do things like archive logs. This is a big part of how our system is setup. We only keep a few days’ worth of logs “active” due to their size (we have an extremely high-volume application). Everything else gets compressed and archived to another location. You’ll also learn how to generate reports that can interact with the web, databases, etc.
There are a ton of books on scripting under Linux out there but this is one of my favorites.
# ./cli-book.sh I <3 the book 'Linux Command Line and Shell Scripting Bible'