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"Pretty print" $PATH, show directories in $PATH, one per line with replacement pattern using shell parameter expansion
Can be used to create path alias. From: https://www.cyberciti.biz/tips/bash-aliases-mac-centos-linux-unix.html. #9

Rename files in batch

Generate a random password 30 characters long

Create a false directory structure for testing your commands
This will make a false directory with the same file names as whatever directory you choose. This is wise to use when testing scripts that alter contents, filenames, or move files. I wrote this after an OOPS I made when renaming a directory of JPGs, PNGs, PSDs that were mixed. I recommend this as I lost over 2000 vacation pictures and some graphics I designed for software and web sites. :( NOTE: This only creates name copies, that data itself is not copied.

whowatch: Linux and UNIX interactive, process and users monitoring tool
whowatch is a interactive, ncurses-based, process and users monitoring tool, which updates information in real time. This is a perfect tool for local and remote servers. It displays information about the users currently logged on to the machine, in real-time. Besides standard information (login name, tty, host, user's process), the type of the connection (ie. telnet or ssh) is shown. Display of users command line can be switch to tty idle time. Certain user can be selected and his processes tree may be viewed as well as tree of all system processes. Tree may be displayed with additional column that shows owner of each process. In the process tree mode SIGINT and SIGKILL signals can be sent to the selected process. Killing processes is just as simple and fun as deleting lines on the screen.

Brute force discover
Show the number of failed tries of login per account. If the user does not exist it is marked with *.

shell bash iterate number range with for loop

Search for an active process without catching the search-process
This does the same thing as many of the 'grep' based alternatives but allows a more finite control over the output. For example if you only wanted the process ID you could change the command: $ ps -ef | awk '/mingetty/ && !/awk/ {print $2}' If you wanted to kill the returned PID's: $ ps -ef | awk '/mingetty/ && !/awk/ {print $2}' | xargs -i kill {}

GRUB2: Set Imperial Death March as startup tune
Kudos to http://www.commandlinefu.com/commands/view/8275/grub2-set-super-mario-as-startup-tune

Show what PID is listening on port 80 on Linux


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