Commands using awk (1,418)

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check open ports (both ipv4 and ipv6)

Have a random "cow" say a random thing
You need to have fortune and cowsay installed. It uses a subshell to list cow files in you cow directory (this folder is default for debian based systems, others might use another folder). you can add it to your .bashrc file to have it great you with something interesting every time you start a new session.

Copy ssh keys to user@host to enable password-less ssh logins.
To generate the keys use the command ssh-keygen

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"

Pipe stdout and stderr, etc., to separate commands
You can use [n]> combined with >(cmd) to attach the various output file descriptors to be the input of different commands.

disable history for current shell session
this will cause any commands that you have executed in the current shell session to not be written in your bash_history file upon logout

list block devices
Shows all block devices in a tree with descruptions of what they are.

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

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"

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.


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