Commands by drerik (3)

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In-Place search/replace with datestamped backup
Does an in situ search-replace but leaves a datestamped backup. A variation with more precision: sed -i.`date +%Y%m%d%H%M%S 's/pattern/replace' [filename]

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" }

Faster find and move using the find and xargs commands. Almost as fast as locate.
Only tested on Linux Ubunty Hardy. Works when file names have spaces. The "-maxdepth 2" limits the find search to the current directory and the next one deeper in this example. This was faster on my system because find was searching every directory before the current directory without the -maxdepth option. Almost as fast as locate when used as above. Must use double quotes around pattern to handle spaces in file names. -print0 is used in combination with xargs -0. Those are zeros not "O"s. For xargs, -I is used to replace the following "{}" with the incoming file-list items from find. Echo just prints to the command line what is happening with mv. mv needs "{}" again so it knows what you are moving from. Then end with the move destination. Some other versions may only require one "{}" in the move command and not after the -I, however this is what worked for me on Ubuntu 8.04. Some like to use -type f in the find command to limit the type.

Turn off your laptop screen on command
echo 'alias monitor_off="sleep 1; xset dpms force standby"' >> ~/.bash_aliases ; . ~/.bash_aliases # now monitor_off does what you think

burn a isofile to cd or dvd
cdrecord must be installed. usefull alias: $alias burniso='cdrecord -v dev=/dev/cdrom' now iso burning is like. $burniso image.iso

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

translates acronyms for you
very handy if you are in irc and absolutely don't know what these guys are talking about. this is a netbsd command, if you are lucky it exists in your distro's package database.

Remove all unused kernels with apt-get
Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version.

Create a new file

df without line wrap on long FS name
-P uses the POSIX output format, which makes information on each file system always printed on exactly one line. "column -t" makes a table from the input.


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