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Ping all hosts on 192.168.1.0/24
-b option takes the broadcast address.

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.

Steve Reich - Piano Phase; interpreter: Bourne-Again Shell.
The Piano Phase piece, by Steve Reich is a minimalist composition which is played on two pianos played at slightly different tempos, a task that's very difficult to accomplish by human players. The auditive effects produced by the cell displacement produce beautiful patterns. See https://en.wikipedia.org/wiki/Piano_Phase . My rendered version: https://ydor.org/SteveReich/piano_phase.mp3 Requires sox to be installed on the system. There are multiple videos on youtube showing different approaches and experiences to this interpretation. There is also a synthesized version. Even if Bash can behave as a powerful pianist, a simple threaded version leaves full room to several time glitches and even negative displacements, the same issues that human pianists experience when playing the piece. The older the computer, the better the chaos added to the result due to the CPU load. Apparently that's the reason Steve Reich composes pieces such as this. Without further ado, please give a warm welcome to the Bash minimalist player on synthesized two-threaded pianos. Please turn off your cellphones.

removing syncronization problems between audio and video
This assumes that there is a 10.2 sec delay between the video and the audio (delayed). To extract the original video into a audio and video composites look at the command on extracting audio and video from a movie

Network Discover in a one liner

Edit the /etc/sudoers config file the right way.
'visudo' is installed by default on most Unix-like systems. If not installed, you can get it from the 'sudo' package. 'visudo' will use the text editor found in your $EDITOR variable, whether it's vi, vim, emacs, nano or gedit. After making changes to the /etc/sudoers file, visudo will check for syntax errors, and notify you of them. This is better than 'vi /etc/sudoers', because of this capability. Rule #1 of system administration- if there is a tool that exists for editing config files, use the tool.

list current processes writing to hard drive

Show the last 20 sessions logged on the machine
change 20 by the number of sessions you want to know (20 it's fair enough)

list files recursively by size

Assign top-level JSON entries to shell variables
A recursive version might be useful too. /dev/tty is used to show which shell variables just got defined.


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