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geoip information
A function that takes a domain name as an argument

Limit the cpu usage of a process
Similar to `cpulimit`, although `prlimit` can be found shipped with recent util-linux. Example: limit CPU consumption to 10% for a math problem which ordinarily takes up 100% CPU: Before: $ bc -l

cpu info

Generate an XKCD #936 style 4 word password
4 random words are better than one obfuscated word http://xkcd.com/936/

remove lines which are longer than 255

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

Count items in JSON array
Pipe any JSON to jq, then count with the appropiate expression and use the | length on the array

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"

Generate a (compressed) pdf from images
use imagemagik convert

Rename files in batch


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