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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 ;)

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"

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

SH
$ cat mod_log_config.c | shmore or $ shmore < mod_log_config.c Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable. What I wanted was a "more" pager that was basically the same as running: $ cat file Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output. After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work. One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the $ tput setab 4; tput setaf 7 command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text. This is one of hundreds of functions I have in my .bash_profile at AskApache.com, but actually won't be included till the next update. If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

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

Remove old kernel packages

Get the Volume labels all bitlocker volumes had before being encrypted
Get information of volume labels of bitlocker volumes, even if they are encrypted and locked (no access to filesystem, no password provided). Note that the volume labels can have spaces, but only if you name then before encryption. Renaming a bitlocker partition after being encrypted does not have the same effect as doing it before.

rename all files with "?" char in name
replace all "?" characters in filename to underscore

encode image to base64 and copy to clipboard
I use it for embedding images in CSS for Stylish, the Firefox addon. Thought it might be useful to others.

get the full description of a randomly selected package from the list of installed packages on a debian system
I put this command on my ~/.bashrc in order to learn something new about installed packages on my Debian/Ubuntu system each time I open a new terminal


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