Commands by knoppix5 (64)

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Print the IPv4 address of a given interface

Tells which group you DON'T belong to (opposite of command "groups") --- uses sed
special thanks to XwZ :)

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Remove all leading and trailing spaces or tabs from all lines of a text file
Bash only, no sed, no awk. Multiple spaces/tabs if exists INSIDE the line will be preserved. Empty lines stay intact, except they will be cleaned from spaces and tabs if any available.

Listing directory content of a directory with a lot of entries
Ever wanted to get the directory content with 'ls' or 'find' and had to wait minutes until something was printed? Perl to the rescue. The one-liner above(redirected to a file) took less than five seconds to run in a directory with more man 2 million files. One can adapt it to e.g. delete files that match a certain pattern.

determine if tcp port is open
Requires netcat.

Nicely display mem usage with ps
Nicely display mem usage with ps.

Find brute force attempts on SSHd
Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

let a cow tell you your fortune

Colorized grep in less
Get your colorized grep output in less(1). This involves two things: forcing grep to output colors even though it's not going to a terminal and telling less to handle those properly.


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