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SSH to a machine's internet address if it is not present on your local network
Ping machine once, waiting 1 second for response until failing. Upon fail, ssh globally, otherwise ssh locally.

Symlink all files from a base directory to a target directory
Symlinks all files in the base directory to the target directory then lists all of the created symlinks.

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

monitor your CPU core temperatures in real time
Watch the temperatures of your CPU cores in real time at the command line. Press CONTROL+C to end. GORY DETAILS: Your computer needs to support sensors (many laptops, for example, do not). You'll need to install the lm-sensors package if it isn't already installed. And it helps to run the `sensors-detect` command to set up your sensor kernel modules first. At the very end of the sensors-detect interactive shell prompt, answer YES to add the new lines to the list of kernel modules loaded at boot.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Explanation of system and MySQL error codes
perror should be installed if mysql-server package is installed

Press enter and take a WebCam picture.
This command takes a 1280x1024 p picture from the webcam. If prefer it smaller, try changing the -s parameter: qqvga is the tiniest, vga is 640x480, svga is 800x600 and so on. Get your smile on and press enter! :)

Cleanly manage tempfiles in scripts
Cleanly create tempfiles using mktemp and remove them using traps instead of removing them in the end of the script. This way, you make sure the tempfiles are removed properly even if the script is killed or interrupted. For a user script in KDE4, you can set TMPROOT using : $ TMPROOT=$(kde4-config --path tmp)

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

"Pretty print" $PATH, separate path per line
from: http://www.unix.com/shell-programming-and-scripting/28047-split-print-path.html


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