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Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Check a server is up. If it isn't mail me.
This version uses netcat to check a particular service.

easily find megabyte eating files or directories
This is easy to type if you are looking for a few (hundred) "missing" megabytes (and don't mind the occasional K slipping in)... A variation without false positives and also finding gigabytes (but - depending on your keyboard setup - more painful to type): $du -hs *|grep -P '^(\d|,)+(M|G)'|sort -n (NOTE: you might want to replace the ',' according to your locale!) Don't forget that you can modify the globbing as needed! (e.g. '.[^\.]* *' to include hidden files and directories (w/ bash)) in its core similar to: http://www.commandlinefu.com/commands/view/706/show-sorted-list-of-files-with-sizes-more-than-1mb-in-the-current-dir

View non-printing characters with cat
Useful to detect number of tabs in an empty line, DOS newline (carriage return + newline). A tool that can help you understand why your parsing is not working.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Quickly CD Out Of Directories Without 5+ Aliases
I wrote this a long time ago, wondering why this wasn't floating around somewhere out there (at least not where I could find).. this seems much more simple than multiple aliases and can cd out of directories easier.

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Convert .wma files to .ogg with ffmpeg

Converts multiple youtube links to mp3 files
Usage: ytmp3 "YTurl" "YTurl2" "YTurl3" "YTurlN" Uses the shift command to let you extract the .mp3 from as many youtube urls as you like (or wherever else youtube-dl is supported) *Requires youtube-dl Orginal chunk of code: youtube-dl -q -t --extract-audio --audio-format mp3 URL taken from here http://www.commandlinefu.com/commands/view/9701/convert-youtube-videos-to-mp3


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