Commands using sleep (289)

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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.

pipe output to notify-send
Route output to notify-send to show nice messages on the desktop, e.g. title and interpreter of the current radio stream

keep a log of the active windows
This logs the titles of the active windows, thus you can monitor what you have done during which times. (it is not hard to also log the executable name, but then it is gets too long)

tunnel vnc port
Foward vnc securely from exampleserver.com

SVN Command line branch merge
This will merge all of the changes from {rev_num} to head on the branch to the current working directory

Debug redirects between production reloads
Watches the headers of a curl, following any redirects and printing only the HTTP status and the location of the possible redirects.

clean up syntax and de-obfuscate perl script
the command show can be run in vim, here is the same thing on the command line $ cat script.pl | perl -MO=Deparse | perltidy

Display a list of all PHP classes that are called statically
Searches all .php files for a static instantiation of a class and displays the class names along with their frequencies.

Trick find -exec option to execute alias
An alias cannot be executed as command in a find -exec line. This form will trick the command line and let you do the job.

Create a continuous digital clock in Linux terminal
Source: http://www.my-guides.net/en/guides/linux/364-how-to-create-a-continuous-digital-clock-in-linux-terminal


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