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2011-03-12 - Confoo 2011 presentation
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Commands by deltaray from sorted by
Terminal - Commands by deltaray - 5 results
utime { date -d @$1; }
2010-05-12 12:21:15
User: deltaray
Functions: date
4

More recent versions of the date command finally have the ability to decode the unix epoch time into a human readable date. This function makes it simple to utilize this feature quickly.

numsum count.txt
2010-01-26 21:53:18
User: deltaray
5

numsum is part of of the num-utils package, which is available in some Linux distros and can also be downloaded at http://suso.suso.org/xulu/Num-utils. It contains about 10 different programs for dealing with numbers from the command line.

Obviously you can do a lot of things that the num-utils programs do in awk, sed, bash, perl scripts, but num-utils are there so that you don't have to remember the syntax for more complex operations and can just think: compute the sum, average, boundary numbers, etc.

dd if=fromfile of=tofile & DDPID=$! ; sleep 1 ; while kill -USR1 $DDPID ; do sleep 5; done
2010-01-12 15:01:44
User: deltaray
Functions: dd kill sleep
Tags: dd kill while sleep
4

This is a more accurate way to watch the progress of a dd process. The $DDPID=$! is needed so that you don't get the PID of the sleep. The sleep 1 is needed because in my testing at least, if you run kill -USR1 against dd too quickly, it will kill it off instead of display the status. So you need to wait a second, probably so that it can configure itself to trap the USR1 signal.

sed -i.bak 's/old/new/g' file
2010-01-06 17:04:05
User: deltaray
Functions: sed
Tags: bash sed
2

sed already has an option for editing files in place and making backup copies of the old file. -i will edit a file in place and if you give it an argument, it will make a backup file using that string as an extension.

while V=$((`date +%s -d"2010-01-01"`-`date +%s`));do if [ $V == 0 ];then figlet 'Happy New Year!';break;else figlet $V;sleep 1;clear;fi;done
2009-12-30 18:42:38
User: deltaray
6

This is the 140 character long new year's countdown timer that was posted to the climagic account on twitter and identi.ca. There are saner ways of doing this of course, but probably none of those would fit. Uses the figlet command, but of course you can replace figlet with just echo if you want.