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Simple XML tag extract with sed
Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...

Create a quick back-up copy of a file
Uses shell expansion to create a back-up called file.txt.bak

Drop or block attackers IP with null routes
Someone might attack on your system. You can drop attacker IP using IPtables. However, you can use route command to null route unwanted traffic. A null route (also called as blackhole route) is a network route or kernel routing table entry that goes nowhere. Matching packets are dropped (ignored) rather than forwarded, acting as a kind of very limited firewall. The act of using null routes is often called blackhole filtering.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

reapair all mySQL/mariaDB databases
while dumping database if you see following error/warning than you have to repair broken tables/rows

Check if the LHC has destroyed the world
This says if the LHC has destroyed the world. Run it in a loop to monitor the state of Earth. Might not work reliable, if the world has actually been destroyed.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Want to known what time is it in another part of the world ?
available timezone can be found in /usr/share/zoneinfo. Other examples: $ TZ=Europe/Paris date; TZ=Australia/Sydney date; TZ=America/New_York date this is based on zoneinfo files on macosx. Your mileage my vary on other unix dialects

Print text string vertically, one character per line.

Check your spelling
For when you need a quick spell check.


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