Commands using grep (1,935)

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view the system memory in clear text
see what's in your memory right now... sometimes you find passwords, account numbers and url's that were recently used. Anyone have a safe command to clear the memory without rebooting?

Print number of mb of free ram
This will show the amount of physical RAM that is left unused by the system.

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

Adding Prefix to File name

Given $PID, print all child processes on stdout
Simpler.

Day of the week of your birthday over the years.
Do you ever want to know which day of week was your birhday! Now you can check that with this command, just set your birh date at the beginning (My bday in the example) and the dates will be revealed. ;)

Countdown Clock
Simple countdown clock that should be quite portable across any Bourne-compatible shell. I used to teach for a living, and I would run this code when it was time for a break. Usually, I would set "MIN" to 15 for a 15-minute break. The computer would be connected to a projector, so this would be projected on screen, front and center, for all to see.

Calculate md5 sums for every file in a directory tree

create dir tree
create tree of dir's in one command

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


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