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Display the top ten running processes - sorted by memory usage
ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT.

blktrace - generate traces of the i/o traffic on block devices
blktrace is a block layer IO tracing mechanism which provide detailed information about request queue operations up to user space. blkparse will combine streams of events for various devices on various CPUs, and produce a formatted output the the event information. It take the output of above tool blktrace and convert those information into fency readable form.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Determine if photos have been rotated to portrait orientation instead of normal landscape orientation
Most people take photos in landscape orientation (wider than it is tall). Sometimes though you turn the camera sideways to capture a narrow/tall subject. Assuming you then manually rotate those picture files 90 degrees for proper viewing on screen or photo frame, you now have a mix of orientations in your photos directory. This command will print out the names of all the photos in the current directory whose vertical resolution is larger than its horizontal resolution (i.e. portrait orientation). You can then take that list of files and deal with them however you need to, like re-rotating back to landscape for consistent printing with all the others. This command requires the "identify" command from the ImageMagick command-line image manipulation suite. Sample output from identify: $ identify PICT2821.JPG PICT2821.JPG JPEG 1536x2048 1536x2048+0+0 8-bit DirectClass 688KB 0.016u 0:00.006

send incoming audio to a Icecast server (giss.tv)
easy way to setup an "internet radio sation", pre-requisite, create an account at an icecast server, in this example, just created beforehand an account at giss.tv. Change the word password, with the respective real password you created at server. Make sure to have installed rec, oggnec, oggfwd and tee. I have a mixer connected at line in, so I can mix music and microphone. This also will produce a local recorded copy of the session, it will be called "streamdump.ogg"

Binary digits Matrix effect
Prints 0's and 1's in The Matrix style. You can easily modify to print 0-9 digits using $RANDOM %10 insted of %2.

left-right mouse buttons (left-handed)

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

execute a shell with netcat without -e
how to execute a shell on a server with a netcat binary which doesn't support -e option


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