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Live filter a log file using grep and show x# of lines above and below

Get info on RAM Slots and Max RAM.

A simple way to securely use passwords on the command line or in scripts
In this example, where the users gpg keyring has a password, the user will be interactively prompted for the keyring password. If the keyring has no password, same as above, sans the prompt. Suitable for cron jobs. ~/.gnupg/passwd/http-auth.gpg is the encrypted http auth password, for this particular wget use case. This approach has many use cases. example bash functions: function http_auth_pass() { gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null; } function decrypt_pass() { gpg2 --decrypt ~/.gnupg/passwd/"$1" 2>/dev/null; }

RTFM function
Sometimes you don't have man pages only '-h' or '--help'.

Verbosely delete files matching specific name pattern, older than 15 days.

Randomize lines (opposite of | sort)
random(6) - random lines from a file or random numbers

Print info about your real user.
To get your effective user: whoami

Replace "space" char with "dot" char in current directory file names

Shell function to create a menu of items which may be inserted into the X paste buffer.
The function will take a comma separated list of items to be 'selected' by xsel -i: $ smenu "First item to paste,Paste me #2,Third menu item" You will then be prompted to choose one of the menu items. After you choose, you will be able to paste the string by clicking the middle mouse button. The menu will keep prompting you to choose menu items until you break out with Control-C.

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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