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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" }

Make sure a script is run in a terminal.
Exit with error if script is not run in a terminal

get bofh excuse from a trusted source :-)

rotate the compiz cube via command line
0-1279 = desktop 1 region = face 1 1280-2559 = face 2 ==>> wmctrl 1280 = wmctrl (1281,...2559) are all the same for a 1280 monitor resolution math: argument of wmctrl -o = ( DesiredFace * HorizontalResolution - 1)

Position the cursor under the current directory line
In case you're like me and like your commands to start on clean lines, especially when you're deep into a 10-level directory tree. This can be added to .bashrc.

create an incremental backup of a directory using hard links
dname is a directory named something like 20090803 for Aug 3, 2009. lastbackup is a soft link to the last backup made - say 20090802. $folder is the folder being backed up. Because this uses hard linking, files that already exist and haven't changed take up almost no space yet each date directory has a kind of "snapshot" of that day's files. Naturally, lastbackup needs to be updated after this operation. I must say that I can't take credit for this gem; I picked it up from somewhere on the net so long ago I don't remember where from anymore. Ah, well... Systems that are only somewhat slicker than this costs hundreds or even thousands of dollars - but we're HACKERS! We don't need no steenkin' commercial software... :)

Find the top 10 directories containing the highest number of files
It can be used to pinpoint the path(s) where the largest number of files resides when running out of free i-nodes

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Find total Terabytes written to a SSD
You must have smartmontools installed for this to work. This also assumes you 512 byte sector sizes, this is pretty standard.

Copy your SSH public key on a remote machine for passwordless login.
Should run on any system with ssh installed.


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