All commands (36)

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repeat a command every one second
Short method of "while x=0; do foo ; sleep 1 ; done"

Play Mediafile in multipart RAR archive on the fly with buffer to seek back and forth
Fire this up in the directory of the RAR achived files to watch any archived movie tv-show or other media without having to unpack it. I also added a cache/buffer to be able to seek back and forth.

list block devices
Shows all block devices in a tree with descruptions of what they are.

change to the previous working directory

Real time duplication of Apache app traffic to a second server
This takes the stream created by apache requests containing jsp and funnels them to another server. I'm using this for simulating real time traffic. The nice command gives ssh maximum CPU cycles, awk & grep strip out everything served by apache. Putting parallel on curl is important because curl is synchronous and waits for the response. Yes, I thought about using wget but it didn't seem any easier. Also, if you figure out how to run this in the background let me know. Every time I background it it stops. If you have multiple front end servers just run multiple instances of this.

Measure, explain and minimize a computer's electrical power consumption
Run this command as root to get enough stats. It works on AMD and Intel machines, including desktops. If ran on a laptop it'll give you suggestions on extending your battery life. You'll need to install PowerTOP if you don't have, via 'apt-get install powertop', etc. To grep the output use: sudo powertop -d | grep ... The many command suggestions PowerTOP gives you alone will increase your command-line fu!

determine if tcp port is open
for udp nmap -sU -p 80 hostname

Ultimate current directory usage command
Based on the MrMerry one, just add some visuals to differentiate files and directories

Get MX records for a domain
command is shorter, output unnecessary longer

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"


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