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Delicious search with human readable output
You can install filterous with $ sudo apt-get install libxslt1-dev; sudo easy_install -U filterous

Check if the files in current directory has the RPATH variable defined
Using gentoo prefix portage I got in a situation where some packages did not contain the needed RPATH variable. This command helped me to find out which ones I should recompile

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

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

show git commit history

watch process stack, sampled at 1s intervals
This command repeatedly gets the specified process' stack using pstack (which is an insanely clever and tiny wrapper for gdb) and displays it fullscreen. Since it updates every second, you rapidly get an idea of where your program is stuck or spending time. The 'tac' is used to make the output grow down, which makes it less jumpy. If the output is too big for your screen, you can always leave the 'tac' off to see the inner calls. (Or, better yet--get a bigger screen.) Caveats: Won't work with stripped binaries and probably not well with threads, but you don't want to strip your binaries or use threads anyway.

Massive change of file extension (bash)
Using bash parameters expansion

Summarize Apache Extended server-status to show longest running requests
Ever need to know why Apache is bogging down *right now*? Hate scanning Apache's Extended server-status for the longest running requests? Me, too. That's why I use this one liner to quickly find suspect web scripts that might need review. Assuming the Extended server-status is reachable at the target URL desired, this one-liner parses the output through elinks (rendering the HTML) and shows a list of active requests sorted by longest running request at the bottom of the list. I include the following fields (as noted in the header line): Seconds: How long the request is alive PID: Process ID of the request handler State: State of the request, limited to what I think are the relevant ones (GCRK_.) IP: Remote Host IP making the request Domain: Virtual Host target (HTTP/1.1 Host: header). Important for Virtual Hosting servers TYPE: HTTP verb URL: requested URL being served. Putting this in a script that runs when triggered by high load average can be quite revealing. Can also capture "forgotten" scripts being exploited such as "formmail.pl", etc.

Anti Syn Ddos
Ddos syn attack

Map the slot of an I/O card to its PCI bus address
Recent hardware may or may not enumerate *both of* these values


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