Vedran Dakic - Linux Command Line and Shell Scripting Techniques: Master Practical Aspects of the Linux Command Line and Then Use It as a Part of the Shell Scripting Process

Master practical aspects of the Linux command line and then use it as a part of the shell scripting process

Vedran Dakic

Jasmin Redzepagic

BIRMINGHAMMUMBAI

Copyright 2022 Packt Publishing

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Writing this book was quite a journey for me. It was a very busy year, compounded by a lot of weird situations earthquakes, COVID-19, health issues in the family basically, this year threw everything that it possibly could at me. Often, I found myself pondering the fact that writing a book is as much therapeutic as it is potentially useful. Writing a book is as much about talking to your inner self as it is about talking to your future audience, especially when knowledge sharing is involved. And, as an ex-IT journalist/editor who used to write IT magazine articles for a living, I was constantly reminded of that fact.

To my co-workers, for offering valuable insight and for being a whiteboard to bounce ideas off (Jasmin, Zlatan, and Andrej). Your coherent and random "in passing" thoughts helped a lot.

To my Packt crew, for putting up with the extreme, parallel universe-level randomness that was my year 2021 thank you.

To my partner, Sanja, for pushing me forward and kicking my derrire, when it needs to be kicked.

Vedran Dakic

My first Linux, Slackware, came on 50+ floppy disks. Installing it was a pain, and somewhere in the middle of the process, a floppy disk was faulty so I started my Linux journey on a machine that was unable to install a GUI. Being confined to a text-only terminal for a few weeks got me hooked.

The nice thing about scripting is that I rarely have any need to leave the terminal even now, 25+ years later, while still being able to do almost anything on any machine I encounter.

Having said that, running scripts would not be possible if it weren't for a few special people in my life, so here goes:

To Filip, my son, who is learning to spell while I try to teach him how to type.

To Dinka, my wife, who keeps us all together through the sun and the rain.

And to all the SysAdmins and SysOps I have encountered during this quarter of a century, exchanging ideas and solutions.

Remember, it's usually DNS.

Jasmin Redzepagic

Vedran Dakic is a master of electrical engineering and computing and an IT trainer, covering system administration, cloud, automatization, and orchestration courses. He is a certified Red Hat, VMware, and Microsoft trainer. He's currently employed as head of department of operating systems at Algebra University College in Zagreb. As part of this job, he's a lecturer for 3- and 5-year study programs in system engineering, programming, and multimedia tracks. Also, he does a lot of consulting and systems integration for his clients' projects something he has been doing for the past 25 years. His approach is simple bring real-world experience to all the courses that he teaches as it brings added value to his students and customers.

Jasmin Redzepagic is a professional master in computer engineering, with a sub-specialization in system engineering, but is a person with many hats worn over the years. Having worked in IT as long as he has, he has been a sound technician, SysOps, DevOps, hardware tester, editor-in-chief of a major magazine, writer, IT support lead, and head of IT at a couple of companies. He is currently employed by Algebra University College in Zagreb. This enables him to have a very wide overview of different technologies while still maintaining his focus implementing and teaching the implementation of open source technologies in the field.

Right now, his main interest is trying to teach his students and clients to understand the immense expanse of tools available for any conceivable task, with his goal being to get people to understand computers as something that is the most formidable tool we, as humanity, have ever had.

Sergio Guidi Tabosa Pessoa is a software engineer with more than 30 years of experience with software development and maintenance, from complex enterprise software projects to modern mobile applications. In the early days, he was working primarily with the Microsoft stack, but soon discovered the power of the Unix and Linux operating systems. Even though he has worked with many languages over the years, C and C++ remain his favorite languages on account of their power and speed.

He has a bachelor's degree in computer science and an MBA in IT management, and is always hungry to learn new technologies, break code, and learn from his mistakes. He currently lives in Brazil with his wife, two Yorkshire terriers, and two cockatiels.

First and foremost, I would like to thank all the people involved in this project, including the author, for such a great piece of work, and those from Packt Publishing for giving me this opportunity. I also would like to thank my beautiful wife, Lucia, and my children, Touch and Lion, for their patience and for allowing me the time needed to help with this book.

Nicholas Cross was born in the UK and educated in New Zealand. He is a distinguished engineer at a tier-1 technology company and has 20 years' experience in Linux. He was working with Linux and Bash scripting a long time before the cloud, automation, and DRY were cool.

Nicholas is passionate about infrastructure automation, DevOps culture, SRE, automation, containerization, and security, and everything else associated with these broad topics.