Commands using cat (504)

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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"

watch your network load on specific network interface
-n means refresh frequency you could change eth0 to any interface you want, like wlan0

Convert the contents of a directory listing into a colon-separated environment variable
Useful for making a CLASSPATH out of a list of JAR files, for example. Also: export CLASSPATH=.:$(find ./lib -name '*.jar' -printf '%p:')

url shortner using google's shortner api
First get a api key for google url shortner from here https://developers.google.com/url-shortener/ Then replace the API_KEY in the command

Use AWS CLI and JQ to get a list of instances sorted by launch time
You can do the filtering natively in the aws cli, without using jq (although jq is awesome!)

Make a zip file with date/time created in the name of the file , zip all sub-directorys
zip -r /tmp/filename-`date +%Y%m%d_%H%M%S`.zip /directory/

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

Rename files in batch

let the cow suggest some commit messages for you

Extract shortcuts and hostnames from .ssh/config
Spits out table that shows your Host->HostName aliases in ~/.ssh/config


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