Commands using useradd (9)

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Get the full path to a file
Part of coreutils - so needs no extra package...

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"

Check availability of Websites based on HTTP_CODE

convert a line to a space

Rename files in batch

Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Lists all listening ports together with the PID of the associated process
Lists all opened sockets (not only listeners), no DNS resolution (so it's fast), the process id and the user holding the socket. Previous samples were limiting to TCP too, this also lists UDP listeners.

Update IP filter for qBittorrent
Downloads Bluetack's level 1 IP blocklist in .p2p format, suitable for various Bittorrent clients.

Using numsum to sum a column of numbers.
numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line. Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

Restore a local drive from the image on remote host via ssh


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