Commands by forestb (5)

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check open ports without netstat or lsof

Erase to factory a pendrive, disk or memory card, and watch the progress

View the latest astronomy picture of the day from NASA.
Substitute feh for the image viewer of your choice. display (part of imagemagick) seems to be a popular choice.

extract column from csv file
extracts the 5th column using the delimiter ','

Function to check whether a regular file ends with a newline
tail -c 1 "$1" returns the last byte in the file. Command substitution deletes any trailing newlines, so if the file ended in a newline $(tail -c 1 "$1") is now empty, and the -z test succeeds. However, $a will also be empty for an empty file, so we add -s "$1" to check that the file has a size greater than zero. Finally, -f "$1" checks that the file is a regular file -- not a directory or a socket, etc.

Determine space taken by files of certain type
Just how much space are those zillions of database logs taking up ? How much will you gain on a compression rate of say 80% ? This little line gives you a good start for your calculations.

Remove apps with style: nuke it from orbit
You can't stand programs x, y, and z. Remove all trace of their existence by adding this function to your config. It will remove the cruft, the settings, and such and such. This function doesn't even give a damn about you trying to remove programs that don't exist: it'll just for loop to the next one on your hit list.

Remove audio stream from a media file
This syntax also works for ffmpeg as avconv is a fork of ffmpeg.

prints message in given argument on on center of screen
$ function echox { echo `tput cup $(($(tput lines))) $(( ($(tput cols) - $(echo "${#1}"))/2 ))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; } echox prints given argument on bottom line center screen in terminal $ function echoxy { echo `tput cup $(($(tput lines)/2)) $(( ($(tput cols) - $(echo "${#1}"))/2))`"$1"`tput cup $(tput lines) $(( $(tput cols)-1 ))`; } exhoxy prints given argument center screen $ function echos { echo `tput cup $(($(tput lines)-2)) $(($(tput cols)-$(echo ${#1})))&&tput sc`"$1"`tput cup $(($(tput lines)-2)) 0 && tput rc`; } $ while [ 1 ]; do echos "`date`"; done echos prints date and time on second from last line (used as status message) you can easily use these functions by placing them in your .bashrc file, make sure to source your .bashrc once you do

Incase you miss the famous 'C:\>' prompt


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