Commands by rootduck (1)

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Create a file of repeated, non-zero
dd can be used with /dev/zero to easily create a file of all zero-bytes. Pipe that through tr and use octal conversions to change the byte values from zero to 0xff (octal 0377). You can replace 0377 with the byte of your choice. You can also use \\0 and \\377 instead of the quoted version.

Counts number of lines
Counts number of lines of code in *.h and *.cc files

Access folder "-"
If you try to access cd - you go to the last folder you were in.

Lines per second in a log file
Another way of counting the line output of tail over 10s not requiring pv. Cut to have the average per second rate : tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2 You can also enclose it in a loop and send stderr to /dev/null : while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

Batch rename extension of all files in a folder, in the example from .txt to .md
Batch rename extension of all files in a folder, in the example from .txt to .md

Check whether laptop is running on battery or cable
If you want to do the same in OS X... grep as necessary for information you need....

Extract audio from Flash video (*.flv) as mp3 file

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

Play random music from blip.fm

retrieve the source address used to contact a given host
on multihomed hosts, connected to several networks, could be usefull to know the source address (local ip address) used to reach the target host, this command does not require root priviledges. The command use a TCP socket, if there is any error the command return an empty string, elsewhere return a valid ip address.

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