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Big (four-byte) $RANDOM
Sometimes, in a shell script, you need a random number bigger than the range of $RANDOM. This will print a random number made of four hex values extracted from /dev/urandom.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
Then pipe to 'xargs ls' for a familiar listing, possibly using find's -print0 and xarg's -0 options.

aplay some whitenoise
Plays whitenoise from /dev/urandom.

Print process run time, average CPU usage, and maximum memory usage on exit
Bash has a built-in time command which provides less functionality than the real time command. Thus we reference /usr/bin/time directly. Since the command isn't very easy to remember you could alias it to something like "cputime" or even just "time".

which process has a port open

Find the process you are looking for minus the grepped one
preferred way to query ps for a specific process name (not supported with all flavors of ps, but will work on just about any linux afaik)

Do some learning...
compgen -c finds everything in your path.

allgclub css

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

Kill google chrome process
This one liner is to kill all google chrome tabs. This works similar to $ killall firefox command which is to kill all firefox processes.


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