Why would it print the colon?

Regex syntax and features vary between implementations. \d isn’t supported by BRE/ERE flavors.

GNU grep supports PCRE, so you can use grep -oP '/dev/loop\d' or grep -o '/dev/loop[0-9]' if you are matching only one digit character.

Thanks a lot for the feedback :)

If he likes games, check out “Invent Your Own Computer Games with Python”: https://inventwithpython.com/invent4thed/

If you are looking for books, check out:

Intermediate:

• Beyond the Basic Stuff with Python — Best Practices, Tools, and Techniques, OOP, Practice Projects
• Pydon’ts — Write elegant Python code, make the best use of the core Python features
• Python Distilled — this pragmatic guide provides a concise narrative related to fundamental programming topics such as data abstraction, control flow, program structure, functions, objects, and modules

Advanced:

• Fluent Python — takes you through Python’s core language features and libraries, and shows you how to make your code shorter, faster, and more readable at the same time
• Serious Python — deployment, scalability, testing, and more
• Practices of the Python Pro — learn to design professional-level, clean, easily maintainable software at scale, includes examples for software development best practices
• Intuitive Python — productive development for projects that last

I have a book for Perl One-Liners as well, which I’m currently revising :)

I’ve written books on regex too, if you are interested in learning ;)

Thanks a lot for the feedback on Coreutils book! It’s so nice to hear that it helped in your thesis.

Regarding the ebook versions, I use pandoc to convert GitHub style Markdown to PDF/EPUB (wrote a blog post about my process here: https://learnbyexample.github.io/customizing-pandoc/). I had to search through stackexchange threads to customize the few things I could. I don’t know how to fix the kind of page breaks you mentioned. But, I’ll try to find a solution. Thanks again for the feedback :)

Hope you find the book useful :)

I’d also suggest these shorter guides to get started:

• https://ferd.ca/awk-in-20-minutes.html
• https://backreference.org/2010/02/10/idiomatic-awk/
• https://earthly.dev/blog/awk-examples/

Into Thin Air by Jon Krakauer

Krakauer examines what it is about Everest that has compelled so many people – including himself – to throw caution to the wind, ignore the concerns of loved ones, and willingly subject themselves to such risk, hardship, and expense. Written with emotional clarity and supported by his unimpeachable reporting, Krakauer’s eyewitness account of what happened on the roof of the world is a singular achievement.

“To Kill a Mocking Bird” is great.

I’ve read his Memory, Sorrow, and Thorn trilogy. Epic dark fantasy, great characters and worldbuilding. The plot is good too, but the pacing goes off rail sometimes.

I read three progression fantasy books in the past three days, so I’m going to take a break and get some of my actual work done :D

Card Mage: Slumdog Deckbuilder by Benedict Patrick (book 1 of a new series) was well written and a compelling read, but I’d have enjoyed it a lot more if it was lighthearted.

Overpowered Dungeon Boy by Benjamin Barreth (2 book completed series) was a lighthearted fun read. The OP main character took a while to warm up to, but many of the side characters were easy to root for.

See also:

• tldr — collection of community-maintained help pages for command-line tools
• explainshell — write down a command-line to see the help text that matches each argument
• General purpose command-line tools — examples for most common usecases
• Bash reference cheatsheet — nicely formatted and explained well
• Bash scripting cheatsheet — quick reference to getting started with Bash scripting

Thanks, that looks interesting, added to my TBR.

Also, just remembered The Stars My Destination by Alfred Bester as another candidate for your request. This is also sci-fi.

If you don’t mind sci-fi: Red Rising by Pierce Brown

And there’s the classic The Count of Monte Cristo by Alexandre Dumas

You can do it in Bash as well. Put this in .inputrc:

"\e[A":history-substring-search-backward
"\e[B":history-substring-search-forward

# or, if you want to search only from the start of the command
"\e[A": history-search-backward
"\e[B": history-search-forward

Inspired by explainshell, I wrote a script (https://github.com/learnbyexample/command_help) to be used from the terminal itself. It is a bit buggy, but works well most of the time. For example:

$ ch grep -Ao
       grep - print lines that match patterns

       -A NUM, --after-context=NUM
              Print NUM lines of trailing context after matching lines.  Places a
              line containing a group separator (--) between contiguous groups of
              matches.  With the -o or --only-matching option, this has no effect
              and a warning is given.

       -o, --only-matching
              Print  only  the matched (non-empty) parts of a matching line, with
              each such part on a separate output line.

I bought a Kindle but hardly ever use it. I was using the web app on my large desktop monitor and I found that comfortable (especially the solarized-like theme) compared to the Kindle device.

I mostly read on Kindle Unlimited. A lot of the progression fantasy and cozy fantasy books are on KU (my current favorite subgenres), so there’s no shortage of books to read. In addition, there’s plenty of self-pub fantasy and sci-fi books (there are two competitions: SPFBO and SPSFC which help in finding good ones to read).