Linux

52752 readers

761 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Posts must be relevant to operating systems running the Linux kernel. GNU/Linux or otherwise.
No misinformation
No NSFW content
No hate speech, bigotry, etc

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago

MODERATORS

[email protected]

275

I wrote an ebook on GNU awk with hundreds of examples and exercises (programming.dev)

submitted 1 week ago by [email protected] to c/[email protected]

21 comments fedilink hide all child comments

Hello!

I am pleased to announce a new version of my CLI text processing with GNU awk ebook. This book will dive deep into field processing, show examples for filtering features, multiple file processing, how to construct solutions that depend on multiple records, how to compare records and fields between two or more files, how to identify duplicates while maintaining input order and so on. Regular expressions will also be discussed in detail.

Book links

To celebrate the new release, you can download the PDF/EPUB versions for free till 06-April-2025.

Or, you can read it online at https://learnbyexample.github.io/learn_gnuawk/

Interactive TUI apps

80+ exercises: https://github.com/learnbyexample/TUI-apps/blob/main/AwkExercises
Brief tutorial: https://github.com/learnbyexample/TUI-apps/blob/main/AwkTutorial

Feedback

I would highly appreciate it if you'd let me know how you felt about this book. It could be anything from a simple thank you, pointing out a typo, mistakes in code snippets, which aspects of the book worked for you (or didn't!) and so on.

Happy learning :)

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 7 points 1 week ago* (last edited 1 week ago) (6 children)

Could someone perhaps explain the major use cases or give a real life example of a time you've needed to use awk? I've been using Linux casually for quite a long time now, and although I learned the basics of the tool, I can't recall having ever felt I had a need for it. If I want to glue a bunch of cli stuff together and need to do some text processing, it generally seems like it'd be easier to just use a simple python script.

Is it more for situations that need to be compatible with most *nix systems and you might not necessarily have access to a higher level scripting language?

[–] [email protected] 6 points 1 week ago (1 children)

Well, if you are comfortable with Python scripts, there's not much reason to switch to awk. Unless perhaps you are equating awk to Python as scripting languages instead of CLI usage (like grep, sed, cut, etc) as my ebook focuses on. For example, if you have space separated columns of data, awk '{print $2}' will give you just the second column (no need to write a script when a simple one-liner will do). This of course also allows you to integrate with shell features (like globs).

As a practical example, I use awk to filter and process particular entries from financial data (which is in csv format). Just a case of easily arriving at a solution in a single line of code (which I then save it for future use).

[–] [email protected] 4 points 1 week ago* (last edited 1 week ago)

Also AWK is made to be fast, right? I suppose doing something in CPython in a non efficient way might not be noticeable with a bit of text, but would show up with a large enough data stream.

load more comments (4 replies)