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Check if a string is into a variable
Returns true (0) if the string is into $var, or false (1) if not.

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

BASH: Print shell variable into AWK
Alternatively: export MyVAR=84; awk '{ print ENVIRON["MyVAR"] }'

Expand shortened URLs
curl(1) is more portable than wget(1) across Unices, so here is an alternative doing the same thing with greater portability. This shell function uses curl(1) to show what site a shortened URL is pointing to, even if there are many nested shortened URLs. This is a great way to test whether or not the shortened URL is sending you to a malicious site, or somewhere nasty that you don't want to visit. The sample output is from: $ expandurl http://t.co/LDWqmtDM

recurisvely md5 all files in a tree
Found this little gem here: http://info.michael-simons.eu/2008/10/25/recursively-md5sum-all-files-in-a-directory-tree/

Slow down the screen output of a command
(example above is the 'ls' command with reduced output speed)

Extract audio from Flash video (*.flv) as mp3 file

convert strings toupper/tolower with tr

Which Twitter user are you?
This will tell you which twitter user you are chronologically. For example, a number of 500 means you were the 500th user to create a twitter account.

Display the top ten running processes - sorted by memory usage
ps returns all running processes which are then sorted by the 4th field in numerical order and the top 10 are sent to STDOUT.


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