Commands by kodango (1)

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Empty a file
The downside of output redirection is that you need permissions. So something like $ > file won't play nicely w/ sudo. You'd need to do something like $ bash -c '> file' instead, you could go w/ $ sudo truncate -s0 file

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

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Ride another SSH agent
Must be done as root - will cause subsequent ssh connections to use the identities available via the [user]'s agent socket.

function to compute what percentage of X is Y? Where percent/100 = X/Y => percent=100*X/Y
This function make it easy to compute X/Y as a percentage. The name "wpoxiy" is an acronym of "what percentage of X is Y"

Upgrade all expired homebrew packages
You probably want to run `brew update` before you run this command

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?

Update twitter via curl
Doesn't require password (asks for it instead)

Compare copies of a file with md5
I had the problem that the Md5 Sum of a file changed after copying it to my external disk. This unhandy command helped me to fix the problem.

Change the primary group of a user


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