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Selecting a random file/folder of a folder
Also looks in subfolders

Prepend section dates to individual entries in a summary log file
Searches for dates on lines by themselves. Uses that date to prepend all rows that contain SEARCHSTRING with the date, until it reaches another line with a date by itself. This fixed an issue with a specific log export where there would be a date, followed by all of the entries for that date.

tar+pbzip2 a dir

Real time duplication of Apache app traffic to a second server
This takes the stream created by apache requests containing jsp and funnels them to another server. I'm using this for simulating real time traffic. The nice command gives ssh maximum CPU cycles, awk & grep strip out everything served by apache. Putting parallel on curl is important because curl is synchronous and waits for the response. Yes, I thought about using wget but it didn't seem any easier. Also, if you figure out how to run this in the background let me know. Every time I background it it stops. If you have multiple front end servers just run multiple instances of this.

Erase to factory a pendrive, disk or memory card, and watch the progress

Pronounce an English word using Merriam-Webster.com
Looks up a word on merriam-webster.com, does a screen scrape for the FIRST audio pronunciation and plays it. USAGE: Put this one-liner into a shell script (e.g., ~/bin/pronounce) and run it from the command line giving it the word to say: $ pronounce lek If the word isn't found in merriam-webster, no audio is played and the script returns an error value. However, M-W is a fairly complete dictionary (better than howjsay.com which won't let you hear how to pronounce naughty words). ASSUMPTIONS: GNU's sed (which supports -r for extended regular expressions) and Linux's aplay. Aplay can be replaced by any program that can play .WAV files from stdin. KNOWN BUGS: only the FIRST pronunciation is played, which is problematic if you wanted a particular form (plural, adjectival, etc) of the word. For example, if you run this: $ pronounce onomatopoetic you'll hear a voice saying "onomatopoeia". Playing the correct form of the word is possible, but doing so might make the screen scraper even more fragile than it already is. (The slightest change to the format of m-w.com could break it).

Install pip with Proxy
Installs pip packages defining a proxy

Instead of writing a multiline if/then/else/fi construct you can do that by one line
instead of writing: if [[ "$1" == "$2" ]]; then echo "$1 is equal $2" else echo "$1 differs from $2" fi do write: [[ "$1" == "$2" ]] && echo "$1 is equal $2" || echo "$1 differs from $2"

List only the directories
to include hidden dirs use: $ tree -adL 1 (with ls, requires 'ls -ad */ .*/')

urldecoding with one pure BASH builtin
You can use ordinary printf to convert "%23%21%2fbin%2fbash" into "#!/bin/bash" with no external utilities, by using a little known printf feature -- the "%b" specifier converts shell escapes. Replace % with \x and printf will understand the urlencoded string. BASH's printf has an extension to set a variable directly, too. So you get to convert urlencoded strings from garble to plaintext in one step with no externals and no backticks.


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