Commands by daa (6)

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Count files beneath current directory (including subfolders)

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"

Super Speedy Hexadecimal or Octal Calculations and Conversions to Decimal.
^Hexadecimal Ten minus Octal Ten is Eight(in Decimal). $ echo "$(( 0xaf )) = $(( 0257 ))" ^Hexadecimal AF and Octal 257 are both Decimal 175.

Apply an xdelta patch to a file
xdelta is a command line program for delta encoding, which generates the difference between two files. This is similar to diff and patch, but it is targeted for binary files and does not generate human readable output. http://xdelta.org/

Recursively chmod all dirs to 755 and all files to 644

Display the history and optionally grep
Place this in your .bash_profile and you can use it two different ways. If you issue 'h' on its own, then it acts like the history command. If you issue: $ h cd Then it will display all the history with the word 'cd'

Chmod all directories (excluding files)
+ at the end means that many filenames will be passed to every chmod call, thus making it faster. And find own {} makes sure that it will work with spaces and other characters in filenames.

Launch a game, like Tetris, when apt-get installing an app larger than 50 Megabytes
Change the APP variable's value to whatever you want to install. Depending on how fast your machine is, you'll want to adjust the value 50 to something else. You might also want to play a different game than Gnometris - just make sure it's a GUI game.

Increase SCT of external USB disk enclosure to one hour.
So I had this 2TB Seagate external disk/USB enclosure which by default would spin-down its internal drive (it enters a standby mode) after four minutes of inactivity.. Spinning-up the inactive drive was an annoying delay when accessing files and also it severely interfered with NFS.. SCT stands for "Standby Condition Timer". To completely disable SCT: $ sdparm --clear STANDBY -6 /dev/sdb To return to original (default) SCT settings: $ sdparm -D -p 0x1a -6 /dev/sdb To verify the settings (before and after): $ sdparm -a /dev/sdb No need for vendor-provided MSWIN tools, etc.

Print the current time on the whole screen, updated every second
http://www.joachim-breitner.de/projects#screen-message now also supports reading stdin continuously to update what it shows, different ?slides? separated by a form feed character. Here, we feed the current time into it each second to create a large clock.

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