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ssh: change directory while connecting
Useful to create an alias that sends you right in the directory you want : alias server-etc="ssh -t server 'cd /etc && $SHELL'"

List all information about all files (in current dir)
This is a funny usage of the traditional command ls. It could be basically simplified as: $ ls -a -l Duplicating arguments is permitted: $ ls -a -l -l And this markup could be shortened as: $ ls -al Extra note: To view filesizes like a pro, pray for your God: $ ls -allah

Search big files with long lines
This is a handy way to circumvent the "Maximum line length of 2048 exceeded" grep error. Once you have run the above command (or put it in your .bashrc), files can be searched using: $ lgrep search-string /file/to/search

How to get an absolute value
Whenever we are only interested in difference between two numbers and not the positive/negative values we can use this in script.

Search and play youtube videos directly to terminal (no X needed)
pyt 'Stairway to heaven - Led Zeppelin' pyt 'brain damage - Pink Floyd' No web browser or even X needed. Just a cli and internet connection! mplayer is pauseable and can skip ahead This may break if youtube changes their search html.

Backup all MySQL Databases to individual files
No need to loop when we have `xargs`. The sed command filters out the first line of `show databases` output, which is always "Database".

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

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.

Binary clock
Fun idea! This one adds seconds and keeps running on the same line. Perl's probably cheating though. :)

Search shoutcast web radio by keyword
Searches for web radio by submitted keyword and returns the station name and the link for listing . May be enhanced to read user's selection and submit it to mplayer.


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