Commands by massiverobot (1)

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check open ports without netstat or lsof

get some information about the parent process from a given process

Copy all files, including hidden files, recursively without traversing backward
You could do the following, however, brace expansion with {} is not defined in POSIX, and therefore not guaranteed to work in all shells. But, if it does, it's more convenient (although it's certainly not less typing): $ cp -r {*,.??*} /dest Sometimes there are times when I need to cp(1), mv(1) or rm(1) files recursively, but don't want to traverse the previous directory by following ../../../../ etc out of the current directory. This command prevents that. The secret sauce is ".??*". The file globbing ensures that it must start with a dot, and be followed by at least two characters. So, three characters must exist in the filename, which eliminates "." and "..".

List your largest installed packages.
Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the $ | sort -rn which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side Also you may need to run this as root as some files can only be checked by du if you can read them ;)

Netcat Relay
This is an example of using 3 hosts, in a netcat relay. first host connects to middle host 1 -> 2 Second hosts redirects to target host 1 -> 2 -> 3 I hope this makes sense.

A function to output a man page as a pdf file
Tested on Fedora 12. This function will take a man page and convert it to pdf, saving the output to the current working directory. In Gnome, you can then view the output with "gnome-open file.pdf", or your favorite pdf viewer.

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

View all images
So you are in directory with loads of pictures laying around and you need to quickly scan through them all

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Change the From: address on the fly for email sent from the command-line
It's very common to have cron jobs that send emails as their output, but the From: address is whatever account the cron job is running under, which is often not the address you want replies to go to. Here's a way to change the From: address right on the command line. What's happening here is that the "--" separates the options to the mail client from options for the sendmail backend. So the -f and -F get passed through to sendmail and interpreted there. This works on even on a system where postfix is the active mailer - looks like postfix supports the same options. I think it's possible to customize the From: address using mutt as a command line mailer also, but most servers don't have mutt preinstalled.


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