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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" }

Trick find -exec option to execute alias
An alias cannot be executed as command in a find -exec line. This form will trick the command line and let you do the job.

Unzip multi-part zip archive
Assuming you have a multi-part archive like "archive.zip archive.z01 archive.z02 ...", unzip will not handle these correctly. If you "fix" the parts into one big file with zip -F before, it works.

Enable programmable bash completion in debian lenny
The really awesome bash completion in debian seems to be an extra package now, which has to be installed. After sourcing /etc/bash_completion it completes almost everything (package names in apt... etc) :-) To make this permanent, put something like this in your .bashrc: if [ -f /etc/bash_completion]; then source /etc/bash_completion fi

Bruteforce dm-crypt using shell expansion
Lost your luks passphrase? You can always bruteforce from the command line. See the sample output, a simple command for the "pass" word, using combinations of upper/lowercase or number replacement. The generated combinations are: for a in {p,P}{a,A,4}{s,S,5}{s,S,5}; do echo $a; done pass pasS pas5 paSs paSS paS5 ...

Synchronize both your system clock and hardware clock and calculate/adjust time drift
Do not run this command if you already have ntpd running! This needs to run as root, for example with sudo: $ sudo ntpdate pool.ntp.org && sudo hwclock --systohc && sudo hwclock --adjust This command will fetch accurate time from NTP servers and synchronize your system clock, then it will use the system clock to synchronize your hardware clock, and will calculate the time drift.

Regenerate the /etc/mtab file

vim insert current filename
insert filename Normal mode: "%p Insert mode: %

generate a unique and secure password for every website that you login to
usage: sitepass MaStErPaSsWoRd example.com description: An admittedly excessive amount of hashing, but this will give you a pretty secure password, It also eliminates repeated characters and deletes itself from your command history. tr '!-~' 'P-~!-O' # this bit is rot47, kinda like rot13 but more nerdy rev # this avoids the first few bytes of gzip payload, and the magic bytes.

Add an audio soundtrack to a series of images to create an flv
Creates a 5 minute flv file, with the given sequence of images and audio with 0.5 fps. The images were created using the following command: for x in `seq 0 300`; do cp ../head.PNG head-`printf '%03d' $x`.png; done You can also inject metadata to seek easier using yamdi as follows: yamdi -i muxed.flv -o video.flv


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