Commands using head (314)

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find established tcp connections without using netstat!!
Fast and easy way to find all established tcp connections without using the netstat command.

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

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

Fork Bomb for Windows
Quick and dirty forkbomb for all flavors of windows Do not use in production. Replace start with a command of your choice, this will just open a new command prompt and is pretty tricky to stop once started

Add page numbers to a PDF
Put this code in a bash script. The script expects the PDF file as its only parameter. It will add a header to the PDF containing the page numbers and output it to a file with the suffix "-header.pdf" Requires enscript, ps2pdf and pdftk.

Find out when your billion-second anniversary is (was).
This is the same command as this one, but for OS X. http://www.commandlinefu.com/commands/view/3053/find-out-when-your-billion-second-anniversary-is-was.

a short counter
Maybe you know shorter ?

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"

Use default value if unassigned
Will use variable value (for variable $my_dir, in this case), an assign a default value if there is none.

Generate random valid mac addresses
Ruby version. Also, a perl version: $perl -e 'printf("%.2x.",rand(255))for(1..5);printf("%.2x\n",rand(255))'


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