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Show the key code for keyboard events include the Fn keys
The keycodes are a result of pressing: Mute (Fn+F1) a

AES file encryption with openssl
To decrypt: openssl aes-256-cbc -d -in secrets.txt.enc -out secrets.txt.new Reference: http://tombuntu.com/index.php/2007/12/12/simple-file-encryption-with-openssl Optional parameter -a makes output base64 encoded, can be viewed in text editor or pasted in email

Screencast of your PC Display with mp4 output
Since ffmpeg on Ubuntu is deprecated, now there is avconv. Please note that the screen area here is set with a predefined format "-s wxga" that is corresponding to "-s 1366x768") There is also the option to add a title in the metadata of the resulting video.

Break lines after, for example 78 characters, but don't break within a word/string
Per default, linux/unix shells are configured with a width of 80 characters. If you like to edit a phrase or string on a line with more than 80 characters it might take long to go there (for example a line with 1000 characters and you like to edit the 98th word which is character 598-603). Maybe you might wish to use 78 characters, because if you forward the text via mail and the text will be quoted (2 extra characters at the beginning to the line "> "), you use 80 characters, otherwise 82, which are lame.

Convert images (jpg, png, ...) into a PDF
Converts images (maybe from scans) into a PDF

Creating A Single Image Video With Audio via ffmpeg

shows history of logins on the server
perfect on a crashed system where you can't use commands like last. for investigation purposes wtmp file can be copied over to a different server and read with utmpdump

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.

Make any command read line enabled (on *nix)
Enable readline even if the command line application is not using it.

Grep without having it show its own process in the results
The trick here is to use the brackets [ ] around any one of the characters of the grep string. This uses the fact that [?] is a character class of one letter and will be removed when parsed by the shell. This is useful when you want to parse the output of grep or use the return value in an if-statement without having its own process causing it to erroneously return TRUE.


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