Commands by BigZ (4)

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Find out how old a web page is
I is for headers only s is for silence curl -Is outputs ONLY headers the pipe and grep is to filter them to Modified only..

See The MAN page for the last command
This works in bash. The "!!:0" limits the argument to man to be only the first word of the last command. "!!:1" would be the second, etc.

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

create screencast (record text and audio simultaneously) using 'script' and 'arecord'
This shell function takes a single argument, which is used as the base name of the .wav, .timing and .session files created. To create a screencast: $ screencast test type and talk ... then type 'exit' or to exit the screencast. test.wav will contain the audio from your screencast. test.session will contain text and control characters needed to paint the screen test.timing will contain timing information needed to synch individual keystrokes in test.session with the audio. to play back: $ aplay test.wav & scriptreplay test.{timing,session} NOTE: because the shell function uses the variable "$!", and bash likes to expand '!' during history expansion, you will need to turn off bash's history before you enter the shell function. This can be achieved using the command $set +H

diff files while disregarding indentation and trailing white space

Capture video of a linux desktop

Find and copy files from subdirectories to the current directory

find an unused unprivileged TCP port
Some commands (such as netcat) have a port option but how can you know which ports are unused?

List apache2 virtualhosts
Lists virtualhosts currently enabled for apache2, showing the ServerName:port, conf file and DocumentRoot

Sort a character string
Sorts a character string, using common shell commands.


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