Commands by leovailati (5)

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Fill up disk space (for testing)
Put into some file. No special purpouse, just for fun...

Insert the last argument of the previous command

Quickly graph a list of numbers
Useful when you've produced a large file of numbers, and want to quickly see the distribution. The value of y halfway along the x axis is the median. Simple! Just create the listOfNumbers.txt file with a number on each line to try it out.

count IPv4 connections per IP
usefull in case of abuser/DoS attacks.

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" }

Shutdown a Windows machine from Linux
This will issue a shutdown command to the Windows machine. username must be an administrator on the Windows machine. Requires samba-common package installed. Other relevant commands are: net rpc shutdown -r : reboot the Windows machine net rpc abortshutdown : abort shutdown of the Windows machine Type: net rpc to show all relevant commands

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"

draw line separator
Even shorter: $ seq -s '*' 120|tr -d '[0-9]'

find and delete empty directories recursively
this will show the names of the deleted directories, and will delete directories that only no files, only empty directories.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.


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