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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"

rename anime fansubs
renames Anime Episodes to files, that can be parsed by sonarr & co

show how many regex you use in your vim today
i want to count how many regex code i have used in vim in a long time so i make a directory in svn host and post record to this directory of course i dont want to post manually so i worte a script to do that and this is the core thing to do

Print today's date in ISO format without calling an external command (bash 4)

clone an USB stick using dd + see its process
The following command will clone usb stick inside /dev/sdc to /dev/sdd Double check you got the correct usb sticks (origional-clone)with fdisk -l.

Read and write to TCP or UDP sockets with common bash tools
Ever needed to test firewalls but didn't have netcat, telnet or even FTP? Enter /dev/tcp, your new best friend. /dev/tcp/(hostname)/(port) is a bash builtin that bash can use to open connections to TCP and UDP ports. This one-liner opens a connection on a port to a server and lets you read and write to it from the terminal. How it works: First, exec sets up a redirect for /dev/tcp/$server/$port to file descriptor 5. Then, as per some excellent feedback from @flatcap, we launch a redirect from file descriptor 5 to STDOUT and send that to the background (which is what causes the PID to be printed when the commands are run), and then redirect STDIN to file descriptor 5 with the second cat. Finally, when the second cat dies (the connection is closed), we clean up the file descriptor with 'exec 5>&-'. It can be used to test FTP, HTTP, NTP, or can connect to netcat listening on a port (makes for a simple chat client!) Replace /tcp/ with /udp/ to use UDP instead.

purge all packages marked with 'rc'
After you install/remove lots of packages, there are many packages marked with 'rc'. This script help you to purge these packages, it will save some spaces from your disk.

Get a stream feed from a Twitter user
*** CAREFULLY READ THE NOTES **** *** THIS DOES NOT WORK "OUT OF THE BOX" *** You'll need a few minutes of CAREFUL reading before making your own Twitter feed: In 2010 simple command line Twitter feed requests all stopped working because Twitter upgraded to SSL security. Https requests for a filtered Twitter stream feed now require a special header called "oauth_header". The benefit is that your stream feed and login info is securely encrypted. The bad news is that an "oauth_header" takes some work to build. Fortunately, four functions, imaginatively named step1, step2, step3 and step4 can be used to build a customized oauth_header for you in a few minutes. Now, go look at "step1" to start creating your own oauth_header!

let the cow suggest some commit messages for you
No need to parse html page, website gives us a txt file :)

Change display resolution
-s must be a valid resolution. You can get a list of valid (and supported) resolutions via `xrandr`.


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