Commands by speirs (1)

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most used unix commands

list files recursively by size

Inverted cowsay
It's quite fun to invert text using "flip.pl" (ref: http://ubuntuforums.org/showthread.php?t=2078323 ). Slightly more challenging is to flip a whole "cowsay". :-)

wrap long lines of a text
wraps text lines at the specified width (90 here). -s option is to force to wrap on blank characters -b count bytes instead of columns

Remove everything except that file
it will remove everything except the file names matching you can use also use wildcards

Run skype using your GTK theme
I use this to make skype blend better into my desktop :) --disable-cleanlooks might not be nescessary to achieve the wanted effect.

let the cow suggest some commit messages for you

Generate an XKCD #936 style 4 word passphrase (fast)
This restricts things 3 ways: 1. No capitalized words, hence no proper names. 2. No apostrophes. 3. Restricts size to range (3,7)

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.

Plot frequency distribution of words from files on a terminal.
Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files.


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