Commands using uniq (255)

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Interactively build regular expressions
txt2regex can be interactive or noninteractive and generates regular expressions for a variety of dialects based on user input. In interactive mode, the regex string builds as you select menu options. The sample output here is from noninteractive mode, try running it standalone and see for yourself. It's written in bash and is available as the 'txt2regex' package at least under debian/ubuntu.

Count the number of characters in each line

Re-emerge all ebuilds with missing files (Gentoo Linux)

Extract rpm package name, version and release using some fancy sed regex
This command could seem pretty pointless especially when you can get the same result more easily using the rpm builtin queryformat, like: $ rpm -qa --qf "%{NAME} %{VERSION} %{RELEASE}.%{ARCH}\n" | sort | column -t but nonetheless I've learned that sometimes it can be quite interesting trying to explore alternative ways to accomplish the same task (as Perl folks like to say: There's more than one way to do it!)

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

Have netcat listening on your ports and use telnet to test connection
This will start a netcat process listening on port 666. If you are able connect to your your server, netcat will receive the data being sent and spit it out to the screen (it may look like random garbage, so you might want to redirect it to a file).

VI config to save files with +x when a shebang is found on line 1
Add this to .vimrc to automatically give scripts with a shebang (e.g., #!/usr/bin/perl) executable permissions when saving. Found @ http://stackoverflow.com/questions/817060/creating-executable-files-in-linux/817522#817522

Make a playlistfile for mpg321 or other CLI player
A short variant if you have only one directory whit only audio files in it.

Make changes in .bashrc immediately available

a function to put environment variable in zsh history for editing
This only makes sense if you are using command line editing. Create the function in your current zsh session, then type eve PATH go 'UP' in your history and notice the current (editable) definition of PATH shows up as the previous command. Same as doing: PATH="'$PATH'" but takes fewer characters and you don't have to remember the escaping.


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