Commands by Agnostos (1)

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diff files while disregarding indentation and trailing white space
**NOTE** Tekhne's alternative is much more succinct and its output conforms to the files actual contents rather than with white space removed My command on the other hand uses bash process substitution (and "Minimal" Perl), instead of files, to first remove leading and trailing white space from lines, before diff'ing the streams. Very useful when differences in indentation, such as in programming source code files, may be irrelevant

multiline data block parse and CSV data extraction with perl
extract data in multiline blocks of data with perl pattern matching loop

Print a row of 50 hyphens
This feels more intuitive to me.

Set audible alarm when an IP address comes online
I'd rather this one on Gnome, as I'm used to be listening some music while working. I've even created a bash function which receives ADDRESS as parameter.

Periodic Display of Fan Speed with Change Highlights
Uses the lm-sensors package in Linux to display fan speed. Grep RPM is used to discover lines containing the text RPM, and sed is used to edit out everything but the RPM number. The watch utility is used to update the display every 10 seconds and -d highlights any changes from the previous value. The eval function of Bash is used to execute the command enclosed in the ".." string.

SSH Copy ed25519 key into your host

Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X
I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: $ echo $'\33[H\33[2J'

Emergency Alien Invasion Warning
When aliens invade Earth, be first to warn your neighbours by placing your computer screen at a window and executing this potentially Earth-saving command. Ctrl C when aliens are defeated.

display a smiling smiley if the command succeeded and a sad smiley if the command failed
you could save the code between if and fi to a shell script named smiley.sh with the first argument as and then do a smiley.sh to see if the command succeeded. a bit needless but who cares ;)

Print the 10 deepest directory paths

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