Commands by kev (116)

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True Random Dice Roll
/dev/urandom is cryptographically secure, and indistinguishable from true random, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool, and hashes the input with SHA-1. As such, this is a quick way to do a "true random" fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com. Change the head(1) count to something other than 5 for more or less numbers.

a short counter
Maybe you know shorter ?

Delete a file/directory walking subdirectories (bash4 or zsh)

Record your desktop
That will capture 200 seconds of video at fullscreen 1680x1050 resolution, but scaled down 25 percent, with 15 frames per second. http://fusioncast.blogspot.com/2007/09/infobyte-how-i-record-my-desktop.html

List available upgrades from apt without upgrading the system

List .log files open by a pid
Uses lsof to display the full path of ".log" files opened by a specified PID.

Perform a C-style loop in Bash.
Print 0 through 99, each on a separate line.

ls -qahlSr # list all files in size order - largest last
I find it useful, when cleaning up deleting unwanted files to make more space, to list in size order so I can delete the largest first. Note that using "q" shows files with non-printing characters in name. In this sample output (above), I found two copies of the same iso file both of which are immediate "delete candidates" for me.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

List all directories only.
Undocumented syntax, but should work on every shell. It'll list all directories in the current one. Change `*/` into globbing `**/` for recursivity.


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