Unix tool tip

'The enjoyment of one's tools is an essential ingredient of successful work.' -- Donald E. Knuth

Was reading up on dc and a source said one of its advantages is its use in obfuscated code competitions. If a language is good for writing obfuscated code, maybe that’s a bad sign.

I talked to a man yesterday who has 5 virtual assistants. I only have two: Python and Bash. I used to have a virtual assistant named Perl but I had to let her go. I got along with her OK but not the rest of my staff.

Linux commands: a practical reference pixelbeat.org/cmdline.html

Sort a file numerically: sort -n

Sed: An Introduction and Tutorial by Bruce Barnett grymoire.com/Unix/Sed.html

You can look for files between a pair of dates using -newermt twice: files with newer modification time than one date and not newer than another date. find . -type f -name "*.tex" -newermt "2025-03-01" ! -newermt "2025-06-01" Note the command has a bang, not a pipe.

Show tabs in a file: cat -T

Ultimate collection of Emacs resources: batsov.com/articles/2011/…

The awk variable NR contains the current record number.

10 patterns in modern Linux tools that trace back to ed(1) johndcook.com/blog/2026/06/0…

In bash, !$ expands to last word of previous command.

Gnu sed allows addresses of the form start~step. For example, 1~2 matches odd-numbered lines.

Useful Perl one-liners catonmat.net/download/perl1… by @pkrumins

Latest edition to my Emacs config file: ;; Toggle frame maximization (when (display-graphic-p) (global-set-key (kbd "C-c m") #'toggle-frame-maximized))

delete from line 3 up to and including first blank line: sed 3,/^$/d filename

Selecting things in Emacs johndcook.com/blog/2017/08/0…

The option -w or --ignore-all-space tells diff to ignore spaces in one line even where the corresponding line has none.

Search man pages for a given string: man -k string

sed script to delete blank lines /^$/d

What's one Linux command you wish you'd learned years ago? reddit.com/r/linux/commen…