Commands by bigeasy (1)

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disable history for current shell session
this will cause any commands that you have executed in the current shell session to not be written in your bash_history file upon logout

continuously print string as if being entered from the keyboard
Cycles continuously through a string printing each character with a random delay less than 1 second. First parameter is min, 2nd is max. Example: 1 3 means sleep random .1 to .3. Experiment with different values. The 3rd parameter is the string. The sleep will help with battery life/power consumption. $ cycle 1 3 $(openssl rand 100 | xxd -p) Fans of "The Shining" might get a kick out of this: $ cycle 1 4 ' All work and no play makes Jack a dull boy.'

Limit the transfer rate and size of data over a pipe
This example will close the pipe after transferring 100MB at a speed of 3MB per second.

remove audio trac from a video file
create a copy of a video file without the audio tracs

archlinux: shows list of packages that are no longer needed
Shows a list of packages which are no longer needed as dependencies of any package installed on your system.

Remove all zero size files from current directory (not recursive)
works only in zsh

pipe commands from a textfile to a telnet-server with netcat
sends commands specified in $commandfile to the telnet-server specified by $telnetserver. to have newlines in $commandfile interpreted as ENTER, save the file in CR+LF (aka "Windows-Textfile") format. if you want to save the output in a separate file, use: $nc $telnetserver 23 < $commandfile > $resultfile

Preview of a picture in a terminal
This command allows you to see a preview of a picture via the terminal. It can be usefull when you are ssh'ing your server without X-forwarding. To have en example of the output you can get with this command see http://www.vimeo.com/3721117 Download at http://inouire.net/image-couleur.html Sources here: http://inouire.net/archives/image-couleur_source.tar.gz

Copy sparse files
This causes cp to detect and omit large blocks of nulls. Sparse files are useful for implying a lot of disk space without actually having to write it all out. http://en.wikipedia.org/wiki/Sparse_file You can use it in a pipe too: $ dd if=/dev/zero bs=1M count=5 |cp --sparse=always /dev/stdin SPARSE_FILE

Server load and process monitoring
In certain cases you mighy need to monitor the server load caused by certain process. For example HTTP, while stress testing apache using ab (apache benchmark) you may want to monitor the server status,load, # of spawned HTTP processes, # of established connections, # of connections in close wait state, apache memory footprint etc.

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