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

Find the package a command belongs to on debian-based distros
Advanced revision to the command 8776 . This revision follows symbolic links. The quotation-marks surrounding $(which $1) allows for graceful handling of errors ( ie. readlink does not complain incase 'which' command generates (null) output)

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.

Compute the numeric sum of a file
In the file data.txt there is a single column of numbers. Sed adds a "+" between lines and xargs prepares the output for bc. The "echo 0" is to avoid to have a "+" at the beginning of the line.

Match a URL
For the record: I didn't build this. Just shared what I found that worked. Apologies to the original author! I decided I should fix the case where http://example.com is not matched for the next time I need this. So I read rfc1035 and formalized the host name regex. If anyone finds any more holes, please comment.

Do some learning...
Just realized how needless the 'ls' has been... This version is also multilingual, since there is no need to grep for a special key word ("nothing"/"nichts"/"rien"/"nada"...). And it makes use of all the available horizontal space.

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

remove repeated pairs of characters e.g. "xtxtxtxt" will become "xt"
This will remove repeated characters e.g. echo "xtxtxtxt" | sed -ru 's/(..)\1{2,}/\1/g' the output will just be "xt"

Oneliner to run commands on multiple servers
Oneliner to run commands on multiple servers over ssh. - First parameter "$1" is the command you want to execute remotely. ( It can be multiple commands e.g. "hostname;uptime") - Second parameter "${@:2}" represents the remote host/s you want to run the command/s on.

Email HTML content
Note, this works because smtp is running


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