Commands using useradd (9)

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List your installed Chromium extensions (with url to each page)
Gives you a list for all installed chrome (chromium) extensions with URL to the page of the extension. With this you can easy add a new Bookmark folder called "extensions" add every URL to that folder, so it will be synced and you can access the names from every computer you are logged in. ------------------------------------------------------------------------------------------------------------------ Only tested with chromium, for chrome you maybe have to change the find $PATH.

Renames all files in the current directory such that the new file contains no space characters.
This is a better version, as it does no command piping, uses for instead of while loops, which allows for a list of files in the current working directory to be natively processed. It also uses the -v/verbose option with mv to let you know what the command is doing. While the command does exactly the same in a better way, I would modify the sed option to replace spaces with underscores instead, or dashes. Please note that you'll receive errors with this command as it tries to rename files that don't even have spaces. This is an alternative to: http://www.commandlinefu.com/commands/view/8761/renames-all-files-in-the-current-directory-such-that-the-new-file-contains-no-space-characters.

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

Get a range on line with sed (first two)
Get the two first lines of a file and quit.

Find all files under a certain directory /home that have a certain suffix at the end of the file name. Show the file and rename them to remove the suffix.

print file without duplicated lines using awk
This create an array 'a' with wole lines. only one occurrence of each line - Not Get lines ++ !

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

Show URL/text in clipboard as QR code
Copy a URL (or Thai text, or whatever) and hit the keyboard shortcut for this fu to display it as a QR code. It's an "air gapped" way to send stuff to your phone [unlike google chart API etc.] as long as you watch out for cameras ;). dependencies [sudo apt-get install]: qrencode xclip xloadimage

Viewable terminal session over network.
connect to it with any network command (including web browser - if you don't mind weird formatting) curl 127.0.0.1:9876 nc 127.0.0.1 9876

Monitor changed files into a log file, with day rotation, using fswatch (MacOS)
This command monitors changes in the current folder structure (subfolders included) and files, and log it into a hidden file in the same folder, called `.file_changes_YYMMDD.log`. Modify the `--exclude` parameters to define what should be skipped.


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