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Syntax Highlight your Perl code

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

Get IP address from domain
shorter (thus better ;-)

Function that outputs dots every second until command completes
Very useful in shell scripts because you can run a task nicely in the background using job-control and output progress until it completes. Here's an example of how I use it in backup scripts to run gpg in the background to encrypt an archive file (which I create in this same way). $! is the process ID of the last run command, which is saved here as the variable PI, then sleeper is called with the process id of the gpg task (PI), and sleeper is also specified to output : instead of the default . every 3 seconds instead of the default 1. So a shorter version would be sleeper $!; The wait is also used here, though it may not be needed on your system. $ echo ">>> ENCRYPTING SQL BACKUP" $ gpg --output archive.tgz.asc --encrypt archive.tgz 1>/dev/null & $ PI=$!; sleeper $PI ":" 3; wait $PI && rm archive.tgz &>/dev/null Previously to get around the $! not always being available, I would instead check for the existance of the process ID by checking if the directory /proc/$PID existed, but not everyone uses proc anymore. That version is currently the one at http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html but I plan on upgrading to this new version soon.

Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

list files recursively by size

Sort a character string
Sorts a character string, using common shell commands.

Watch Star Wars via telnet
Use Ctrl-] to stop it.

Perpetual calendar
Gets any date since today. Other examples of recognized expressions are "2 years 4 days ago", "7 months" (in the future), "next Sunday", "yesterday", "tomorrow", etc.

Make changes in .bashrc immediately available
You may want to just use the shortcut "." instead of "source"


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