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Dock Thunderbird in system tray and hide main window
Dock Thunderbird in system tray and hide main window. Very useful for startup scripts. Of course you can dock any app of your choice.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

archlinux: shows list of packages that are no longer needed
Shows a list of packages which are no longer needed as dependencies of any package installed on your system.

Remove lines that contain a specific pattern($1) from file($2).
The -i option in sed allows in-place editing of the input file. Replace myexpression with any regular expression. /expr/d syntax means if the expression matches then delete the line. You can reverse the functionality to keep matching lines only by using: $ sed -i -n '/myexpression/p' /path/to/file.txt

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

Recursively remove .svn directories from the current location

Quickly ping range of IP adresses and return only those that are online
Tested in Debian, ymmv. - c 1 : send only one ping;; -W 1: wait for one second and then exit ping, assuming target IP is not available; change as needed (-W 0.5 for half a second, smaller or greater value depending on network speed/latency)

Find Duplicate Files (based on size first, then MD5 hash)
This dup finder saves time by comparing size first, then md5sum, it doesn't delete anything, just lists them.

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"

Remote screenshot
Admittedly, I'd never have thought of this without the earlier examples, but here's one that you can execute from your workstation to just display the image from another, without separately doing a file transfer, etc. By the way, I hear a loud beep coming from the other room, so I guess it's not too stealthy :-D


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