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Remove duplicate rows of an un-sorted file based on a single column
$F[0] filters using first word. $F[1] - 2nd, and so on.

Webcam view with vlc
Quick command to test your webcam. Press 'f' to toggle fullscreen. Can also use 'vlc v4l2://' if you want gui controls. For higher/smoother framerate lower the default resolution: $ cvlc v4l2:// :v4l2-width=320 :v4l2-height=240 &

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"

Synthesize text as speech
The Festival Speech Synthesis System converts text into sound. Or: links -dump http://youfavoritewebsite.com | festival --tts

Bash command to convert IP addresses into their "reverse" form

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

Compare prices in euro of the HTC Desire on all the european websites of Expansys.
You think Expansys in all these countries will sell the HTC Desire for the same price? Well, you'll be surprised. Most of them will be sold at 499.99 EUR but the cheapest can be found in Germany and the most expensive, in Belgium.

a short counter
Maybe you know shorter ?

find an unused unprivileged TCP port
perl-less way

Print summary of referers with X amount of occurances
This prints a summary of your referers from your logs as long as they occurred a certain number of times (in this case 500). The grep command excludes the terms, I add this in to remove results Im not interested in.


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