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Function to remove a directory from your PATH
Function to remove a specified path from your PATH environment variable.

Big (four-byte) $RANDOM
Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

Delete all non-printing characters from a file
tr has some predefined sets of characters that are more convenient to use than characters codes

Send an email from the terminal when job finishes
Might as well include the status code it exited with so you know right away if it failed or not.

generate random password (works on Mac OS X)
Prepending env LC_CTYPE=C fixes a problem with bad bytes in /dev/urandom on Mac OS X

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Generate a random password 30 characters long
According to the gpg(1) manual: --gen-random 0|1|2 count Emit count random bytes of the given quality level 0, 1 or 2. If count is not given or zero, an endless sequence of random bytes will be emitted. If used with --armor the output will be base64 encoded. PLEASE, don't use this command unless you know what you are doing; it may remove precious entropy from the system! If your entropy pool is critical for various operations on your system, then using this command is not recommended to generate a secure password. With that said, regenerating entropy is as simple as: $ du -s / This is a quick way to generate a strong, base64 encoded, secure password of arbitrary length, using your entropy pool (example above shows a 30-character long password).

rotate the compiz cube via command line
0-1279 = desktop 1 region = face 1 1280-2559 = face 2 ==>> wmctrl 1280 = wmctrl (1281,...2559) are all the same for a 1280 monitor resolution math: argument of wmctrl -o = ( DesiredFace * HorizontalResolution - 1)

find . -name

Testing hard disk writing speed


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