Commands by cbpowell (1)

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Cleanup firefox's database.
Sqlite database keeps collecting cruft as time passes, which can be cleaned by the 'vacuum;' command. This command cleans up the cruft in all sqlite files relating to the user you have logged in as. This command has to be run when firefox is not running, or it will exit displaying the pid of the firefox running.

Update zone file Serial numbers
Will edit *.db files in the same directory with todays date. Useful for doing a mass update to domains on a nameserver, adding spf records, etc. Looks for a string starting with 200 or 201 followed by 7 numbers, and replaces with todays date. This won't overwrite Ip's but i would still do some double checking after running this. Make sure your server's date is correct, otherwise insert your own serial number. $rndc reload should usually follow this command.

Remount a usb disk in Gnome without physically removing and reinserting
Remounts a usb disk /dev/sdb, without having to physically remove and reinsert. (Gnome desktop)

Create a new file

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.

restoring some data from a corrupted text file
man tac When there is a bad block in the middle of your file, you can see its begninning with `cat' and its end with `tac'. But both commands terminates with an error. So this sequence rebuilds a new file without badblock.

Rename files in batch

Check if it's OK to spawn tmux. Bool's Rools.
The command cechks if we are connected to a X11 console, if the $TERM var noct yet contains a "screen" derivat, and only then attachs to tmux. You could add a test for interactive shell [[ $- == *i* ]] but your .bashrc has that already, I bet.

Finding files with different extensions
This is the way how you can find header and cpp files in the same time.

get the top 10 longest filenames

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