Commands by makda (0)

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copy partition table from /dev/sda to /dev/sdb

Find out current working directory of a process

count IPv4 connections per IP
usefull in case of abuser/DoS attacks.

Wait for file to stop changing
Here's a way to wait for a file (a download, a logfile, etc) to stop changing, then do something. As written it will just return to the prompt, but you could add a "; echo DONE" or whatever at the end. This just compares the full output of "ls" every 10 seconds, and keeps going as long as that output has changed since the last interval. If the file is being appended to, the size will change, and if it's being modified without growing, the timestamp from the "--full-time" option will have changed. The output of just "ls -l" isn't sufficient since by default it doesn't show seconds, just minutes. Waiting for a file to stop changing is not a very elegant or reliable way to measure that some process is finished - if you know the process ID there are much better ways. This method will also give a false positive if the changes to the target file are delayed longer than the sleep interval for any reason (network timeouts, etc). But sometimes the process that is writing the file doesn't exit, rather it continues on doing something else, so this approach can be useful if you understand its limitations.

Get names of files in /dev, a USB device is attached to
This command lists the names of your USB devices connected and what file in /dev they are using. It's pretty useful if you don't have an automount option in your desktop or you don't have any graphical enviroment.

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"

easily convert one unit to another
Easily convert units of similar measurement. May also be invoked alone, units.

Remove all unused kernels with apt-get
This will remove all installed kernels on your debian based install, except the one you're currently using. From: http://tuxtweaks.com/2009/12/remove-old-kernels-in-ubuntu/comment-page-1/#comment-1590

list files recursively by size

Create a bunch of dummy text files
Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

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