URLs du Jour

2009-01-13

  • At Tech Central Station, Max Borders discusses the power of a particularly powerful metaphor to derange thought: that the economy is a "machine"—a complex one to be sure, but still a machine—that can be "fixed" if only the right geniuses with correct values are put in charge.
    But the whole idea of fixing, running, regulating, designing, or modeling an economy rests on the notion that, if the right smart guys are at the rheostats, the economy can be ordered by intelligent design. But the economy is no mechanism. There is no mission control. Government cannot swoop down like a deus ex machina to explain the inexplicable and fix the unfixable. Why? Because the knowledge required to grasp each of the billions of actions, transactions and interconnections would fry the neural circuitry of a thousand Ben Bernankes. This is what F. A. Hayek called the knowledge problem. Knowledge, Hayek reminded us, is not concentrated among a few central authorities but is dispersed around society. That's why bad unintended consequences follow government interventions like black swans.
    As Leonard Read pointed out long ago, the people who would impose their grand economic visions on us can't even make a pencil.

  • In related news: taxation is complicated enough so that the incoming Secretary of the Treasury can't avoid making a "common mistake" (which, um, only came to light once he was nominated). He's had to pay somewhere around $10K in interest on "mistakes". Fortunately, for him, "the IRS waived all penalties."

    Not surprisingly, ma belle Michelle is all over this.

  • I didn't like the movie Wanted. But Andrew Klavan really didn't like it:
    Film-wise, it's more or less okay, the first half an entertaining Matrix ripoff, the second half a lot of so-so CGI bang-bang. But idea-wise, it's pure fascism--although Angelina Jolie shows us her butt so maybe fascism's not as bad as we thought.
    I forgot to mention the butt thing. But doesn't she do that in every movie?

Rotating GNOME Wallpaper in Fedora 10

We don't usually talk programming here on Pun Salad, but …

I wrote a small Perl script a number of years ago that would rotate the "wallpaper" background on my Linux boxes, changing it to the least-recently-used JPEG file in a directory collection I've maintained. I stuck the script in my crontab file to execute every hour, and—voila!—I was mildly entertained by the automatically-changing background of scenic vistas, cute animals, etc.

This stopped working when I upgraded to Fedora 10. And, eventually, I noticed: my background was stuck on the same picture throughout my login session.

Telling symptom: the script worked fine when I ran it from the command line, but it was not working out of crontab.

Explanation: In GNOME (Fedora's default desktop software), the actual background-changing work is performed by a program called gconftool-2; the latest version requires an environment variable (specifically, DBUS_SESSION_BUS_ADDRESS) to be set in order to affect the current session's configuration. This environment variable is automatically provided to programs run from the command line, but aren't normally available to programs run out of crontab.

So I had to add some lines to my script to dig out the value of this variable and make it avaiable to gconftool-2; fortunately, this article from the Srijith Unplugged blog showed a technique for making that happen in a Bash script that wasn't tough to translate to Perl.

More information and a pointer to my script is on my "Hacks" site here.


Last Modified 2012-10-08 8:25 PM EST