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

Tail postfix current maillog and grep for "criteria"
Tail curren postfix maillog.

Returns the number of cores in a linux machine.
Original article in http://www.howtogeek.com/howto/ubuntu/display-number-of-processors-on-linux/

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Windows telnet
Check if TCP port is reacheable

TCP and UDP listening sockets
This command show listening sockets TCP and UDP. Useful for stop unwanted services from linux.

A signal trap that logs when your script was killed and what other processes were running at that time
trap is the bash builtin that allows you to execute commands when the current script receives a particular signal. Uses $0 for the script name, $$ for the script PID, tee to output to STDOUT as well as a log file and ps to log other running processes.

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.

Resume an emerge, and keep all object files that are already built
For Gentoo: If you do not use this command, portage will fetch the source again, and rebuild the hole application from the top. This command make portage keep all files that ar allready built

Console clock
A console clock with the current time.


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