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Run a command as root, with a delay
$ sleep 1h ; sudo command or $ sudo sleep 1h ; sudo command won't work, because by the time the delay is up, sudo will want your password again.

Convert encoding of given files from one encoding to another

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" }

Connect-back shell using Bash built-ins
Connect-back shell using Bash built-ins. Useful in a web app penetration test, if it's the case of a locked down environment, without the need for file uploads or a writable directory. -- /dev/tcp and /dev/udb redirects must be enabled at compile time in Bash. Most Linux distros enable this feature by default but at least Debian is known to disable it. -- http://labs.neohapsis.com/2008/04/17/connect-back-shell-literally/

make a log of a terminal session
Creates a log of a session in a file called typescript. Or specify the file with: $script filename Exit the session with control-d.

quickly backup or copy a file with bash
less symbols, tab completion. including # export SIMPLE_BACKUP_SUFFIX="_`date +%F`" in your .bashrc provides you to easily timestamp your files

Open files in a split windowed Vim
-o acts like :spit. Use -O (capital o) for side-by-side like :vsplit. Use vim -d or vimdiff if you need a diff(1) comparison. To split gnu Screen instead of vim, use ^A S for horizontal, ^A | for vertical.

Random Number Between 1 And 256
It takes a byte from /dev/random whose source is the kernel entropy pool (better source than other solutions).

See system users

Batch edition of all OpenOffice.org Writer files in the current directory (body text)
This function does a batch edition of all OOO3 Writer files in current directory. It uses sed to search a FOO pattern into body text of each file, then replace it to foo pattern (only the first match) . I did it because I've some hundreds of OOO3 Writer files where I did need to edit one word in each ones and open up each file in OOO3 gui wasn't an option. Usage: bsro3 FOO foo


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