*nix Tip of the Day: Unix Time

Posted Sun 06 March 2011 21:43 under category tips

As the unix-savvy among you probably know, there is One True Way to tell the time: the number of seconds elapsed since midnight on January 1, 1970 +0000. It's an extremely convenient way for computers to represent the time, since it's just an integer that goes up. There's no parsing to be done, and arithmetic is just regular math. If you want a brain-numbingly-detailed overview, Wikipedia's article on unix time is, as usual, sufficient.

However, what I'd like to talk about here is converting back and forth between unix time and meatware time. I imagine ...

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sietchtabr reboot

Posted Sun 27 February 2011 12:56 under category tech

I have a VM slice that I use to run DNS, a bzflag server, and a few other incidental things. This is what I see on it right now:

% uptime
12:05:13 up 450 days, 15:17,  5 users,  load average: 1.93, 1.35, 0.60

It's currently running Debian lenny, but I decided that I wanted to get with the times and upgrade it to squeeze. As expected the upgrade was fairly painless (took me a bit to figure out that booting by label was broken and I needed to boot by disk UUID), but it ...

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Linix Tip of the Day: SystemTap

Posted Wed 16 February 2011 09:08 under category tips

The other day, one of my co-workers, Evan, presented an interesting problem to me. Every day, at some point, a file named ] gets created in his home directory. He assumes that it is being created by a script with a typo in it... somewhere. But how to find out? It's a hard thing to grep for.

My initial solution was to use inotify (which you might remember from a previous post) combined with libnotify to alert him if it happens while he was at his computer. It looked like the following:

$ inotifywait -t 0 --exclude='.*[^]]$' $HOME && notify-send "something just ...
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A word on dreams

Posted Mon 31 January 2011 10:56 under category personal

We use the terms "bad dream" and "nightmare" almost synonymously. I contend that this is a frightfully naïve perspective. When we wake from a nightmare, we shortly realize that the floor isn't made of spiders, that all of the clowns are safely at the circus. But a dream in which we are happy... ah! Such a dream can color the real world world a darker shade long after the dreamer has awoken. These are truly the bad dreams.

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Firefox 4 and Vimperator 3

Posted Thu 27 January 2011 19:04 under category tech

firefox

I've been using Google Chrome's dev channel for the past year or so as my primary browser, but between some questionable aesthetic decisions and Chrome's tendency to segfault every hour or so for the last few dev releases, I decided that it's time to give up on the faster browser in exchange for the usable browser. Toward that end, I'm going back to Firefox. I hear that Firefox 4 is the next cool thing, so I set it up on my work machine (4.0b10pre, if you're interested). And, of course, since I am ...

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*nix Tip of the Day: Waiting in Scripts

Posted Sat 04 December 2010 16:22 under category tips

Scripting is what makes Unix-like operating systems great. Every *nix, be it Linux, BSD, OS X, AIX, Solaris, or whatever other random distribution you can come up with, comes with a capable shell (or three) and a good set of basic utilities. Where a Windows administrator has to either fall to the horror that is Batch files, write code in a big, heavy programming language language, or submit to the terrible dominance of “management utilities”, a Unix system administrator has tons of the tools at his disposal to fix and automate things. I could talk about scripting forever (it is a substantial portion of my job), but today I'm just going to talk about one small facet: waiting for things to happen.

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