Commands using iptables (37)

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Automatically find and re-attach to a detached screen session
-RR option is used to resume the first appropriate detached screen session

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"

Load average + API google chart
limite = threshold

Get your Firefox bookmarks
Extracts yours bookmarks out of sqlite with the format: dateAdded|url

Reload all sysctl variables without reboot
Use `sysctl -p` without argument will only load /etc/sysctl.conf, but user configs always put in /etc/sysctl.d/*.conf, `sysctl --system` will load all the config files

Create a new file

One command line web server on port 80 using nc (netcat)
Very simple web server listening on port 80 will serve index.html file or whatever file you like pointing your browser at http://your-IP-address/index.html for example. If your web server is down for maintenance and you'd like to inform your visitors about it, quickly and easily, you just have to put into the index.html file the right HTML code and you are done! Of course you need to be root to run the command using port 80.

Remove audio stream from a media file
This syntax also works for ffmpeg as avconv is a fork of ffmpeg.

get stdout to variable and stdout at sametime
Sometimes you want to write the script output to stdout but you need to send it to email. If you use: $ var="$( ls / )"; $ echo -e "$var"; works but, you need to wait the script terminate to bufferize then print the output var; With this way, you can use/work/print the output before the variable receive all the output content, then after it you can use the variable for anything else, like send email.

Delete only binary files in a directory
Please note that binary file checking is NOT perfect. So, use it with caution. It does not delete hidden files whose name has a leading '.' character. And it regards an empty file as a binary file.


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