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Delete empty directories
Recursively delete empty directories. Use with care.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

updatedb for MAC OSX
MAC OSX doesn't come with an updatedb command by default, this will emulate the updatedb thats on a typical Linux OS. Simply add it to your ~/.bash_profile

How to establish a remote Gnu screen session that you can re-connect to
Long before tabbed terminals existed, people have been using Gnu screen to open many shells in a single text terminal. Combined with ssh, it gives you the ability to have many open shells with a single remote connection using the above options. If you detach with "Ctrl-a d" or if the ssh session is accidentally terminated, all processes running in your remote shells remain undisturbed, ready for you to reconnect. Other useful screen commands are "Ctrl-a c" (open new shell) and "Ctrl-a a" (alternate between shells). Read this quick reference for more screen commands: http://aperiodic.net/screen/quick_reference

Quick and dirty convert to flash
This converts any media ffmpeg handles to flash. It would actually convert anything to anything, it's based on the file extension. It doesn't do ANY quality control, sizing, etc, it just does what it thinks is best. I needed an flv for testing, and this spits one out easily.

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"

Diff files over SSH
Sometimes you need to compare two config files on different servers. Put the file names into the above script and let 'er rip.

C function manual

Find the package that installed a command

Freshening up RKhunter
Not everyone reads manpages. Aliasing this command will help with the task of doing audits with RKhunter. It will check for the latest version, update the definitions and then run a check on the system. Hint: alias that in your .bashrc to make life for your fingers easier.


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