Thursday, December 18, 2008

I CAN HAS SQRT?

I was pointed at this today. Although it doesn't follow the LOLCODE spec as I read it (perhaps it follows some consensus about future specs that I've not paid attention to), it's neat: square roots in LOLCODE.

Friday, December 12, 2008

ForwardAgent

Periodically I'll learn something so useful I immediately wish I'd known it years ago, and so simple I'm almost ashamed to admit it was news to me. UNIX systems in general, and Linux in particular, seem to be especially good at coming up with such things. Yesterday was one such experience, when I learned about SSH's ForwardAgent option.

SSH agents let you use passphrase-protected SSH keys without typing in your passphrase all the time. If I connect from Host1 to Host2 via SSH, Host2 sends me a key challenge and my SSH agent answers it authenticate me. But if I then use SSH to go from Host2 to Host3, by default I need to either type a password on Host3 (which is annoying and not terribly secure) or copy my private key to Host2 (which is annoying and terribly not secure) (yes, I meant to write it that way).

ForwardAgent (configured in ssh_config) allows Host3 to send a key challenge to Host2, and Host2 to forward the challenge to the SSH agent living on Host1. It's as if my private key followed me wherever I went. Neat :)

Thursday, December 11, 2008

Woah... a MUMPS person

Yesterday, on the bus, I found out an otherwise unassuming acquaintance who works at the local veterans' hospital, is a devotee of the VA's VistA health information system, and the MUMPS system that supports it. I knew there were people still forced to use MUMPS; I didn't know anyone actually enjoyed it.

The VA open sourced VistA while I was working in medical software. I spent a few hours typing inscrutable strings of strange characters into an only semi-responsive console before giving up with the conclusion that anything that esoteric wouldn't be much of a competitor to our product. Which is not to say our product actually worked, just that it was easier to install.

Sunday, December 7, 2008

New sourdough starter

We like sourdough. It's neat, it's fun, it's yummy... but we've had problems with sourdough starters. I got a sourdough start from a coworker a while back. It came with a pedigree: a settler had started it over a century before in the Joe's valley area of Utah, and it had been shared and passed down through families ever since. This coworker grew up on sourdough pancakes from this same starter. For a while it worked well, and even when we didn't remember to treat it kindly, it still made decent bread. We learned that even though we couldn't see the difference between quality wheat and crummy wheat, the starter could, and flour from good wheat would rise better. We learned that the electric flour mill we used heated the flour too much, and the starter wouldn't grow well, and when we finally got our manual grain mill the starter worked much better. But eventually the starter just got nasty. Sourdough recipes talk about a "pleasant sour odor" but ours was far from pleasant. It was more like sour feet than sour dough.

So we started a new one. It's easy enough -- mix flour and water and let it sit out for a few days, periodically adding more flour and more water, and occasionally changing the bowl it's in to a nice clean one. Cheesecloth or perforated plastic wrap on the top is good for letting wild yeasts in and keeping bugs out, and in a few days you get something kinda foamy. That starter worked decently enough, but since last summer we've been fairly busy, and haven't been able to feed it regularly. So the other day we retired it from its dark corner of the refrigerator where it had spent the last few months, and I ground up some rye to start a new one.

Rye is supposed to be better than other grains for starting sourdough cultures, because it has less phytic acid than other grains. Eventually we'll have to -- gently -- introduce wheat flour to this starter; it takes a while for a starter to make the transition to a new flour. But for now, we've got a pasty flour blob sitting in a bowl showing faint signs of bubbling. This being winter, the wild yeasts we collect aren't as active and our kitchen counter isn't as warm, so it takes a while for it to get started, but here are some pictures, just for kicks...