Author: Paul Tomblin

What were they thinking?

Update:Added the “Where is this body you want disposed of” picture.

We had a Energy Star energy audit of our house recently. One of the things the audit mentioned that there was some asbestos on one of the vent pipes in the basement, and that would have to be “abated” before they could work. Today I decided to take care of it. The pipe in question goes through “the scary room”, one of two dirt floored areas of the basement. Until today, I’ve never set foot in either one of them. There is no apparent reason why this particular pipe has been wrapped in asbestos – the portion of the pipe that is wrapped isn’t close to the furnace so it’s not very hot, nor is it in contact with insulation or something flammable. The register it serves is in the “breakfast nook”, which we suspect wasn’t part of the original build of the house.

I got advice from experts in the field who assured me that the sort of asbestos that forms into sheets isn’t the dangerous kind, but I should still take some precautions.

So armed with a tyvec painter’s coverall, dust mask, googles and rubber gloves, I entered the scary room to do battle with the evil asbestos. And that’s when I discovered that the asbestos wrap evidently held condensation or external water against the bottom of the vent, and now the vent pipe has rusted completely away on the bottom. But it’s fine at the top, which means there is a part between the bottom and the top where there are sharp edges and flakes of rust. So instead of just removing the asbestos wrapping, I ended up hacking out the whole rusty pipe, and stomping it flat to throw it away. And the sharp edges cut my gloves to ribbons, but at least I didn’t get any visible cuts in my skin. Unfortunately the unwrapped part of the pipe only had one hangar on the whole length, so it fell down without the added support on one end. And the “box” where it went into the register in the breakfast nook was also wrapped and rusty so I had to remove it as well.

It wasn’t until after I was done that I noticed the notice on the air mask that said it’s not for asbestos. Sigh.

Well, the whole thing is down now. Hopefully I didn’t do myself any damage doing it.

No, that’s not good either

I wrote about some work I’ve been doing on the Waypoint Generator in Rants and Revelations » Getting there, still some collateral damage. In that, I said I wanted to do some more testing. Well, I did. I reloaded the entire DAFIF dataset. The test took 4 straight days to run, and that’s not including losing a day or so when my router lost its mind. And what this test told me is that the new algorithm for eliminating duplicate points is overzealous.
For instance, it classified two Canadian airports, CYEE Midland/Huronia and CNL8 Wyevale/Boker Field, as being the same. They’re actually nearly two nautical miles apart.

I was calling points the same if the types matched and they’re within 0.05 degrees latitude and 0.05 degrees longitude of each other. Unfortunately that is just about 3 nautical miles in the north/south direction, which this test has shown is too wide a net.

The problem is that I want to spot duplicates when a waypoint changes id, AND when they update the coordinates. I’ve seen places where they’ve updated the coordinates by half a degree, especially in the case of user-entered data.

I think what I’m going to have to do is trust that the coordinates aren’t going to change a whole bunch at the same time the id changes. So what I’ll do is call something a duplicate if it’s within 0.05 degrees if the ids match, but within 0.01 degrees if the ids don’t match. That’s less than a nautical mile, and it would be pretty odd to find two airports within a nautical mile of each other. (A lot less odd to find heliports or reporting points, unfortunately.)

Damn, this means another multi-day test run, unfortunately.

If your VCR is flashing 12:00…

I saw (and stole) a sig quote once that said “If your VCR is flashing 12:00, then maybe Linux isn’t the OS for you”. Today I had a similar experience.

I host a bunch of mailing lists on Mailman at my domain list.xcski.com. Some of them I run, and some, like the ones for the Linux Users Group of Rochester (LUGOR), I just host and let somebody else run. One of the things that Mailman does is automatically send out a monthly ‘password reminder’ – as well as reminding people that they belong to one or more mailing lists and giving them the password and url they need to know if they need to make changes to their subscription, it’s also a good way for Mailman to test if the address is still valid so it can unsubscribe invalid addresses automatically.

The monthly mailing list reminder looks like:


This is a reminder, sent out once a month, about your list.xcski.com
mailing list memberships. It includes your subscription info and how
to use it to change it or unsubscribe from a list.

You can visit the URLs to change your membership status or
configuration, including unsubscribing, setting digest-style delivery
or disabling delivery altogether (e.g., for a vacation), and so on.

In addition to the URL interfaces, you can also use email to make such
changes. For more info, send a message to the '-request' address of
the list (for example, mailman-request@DOMAINNAME) containing just
the word 'help' in the message body, and an email message will be sent
to you with instructions.

If you have questions, problems, comments, etc, send them to
mailman-owner@DOMAINNAME. Thanks!

Passwords for YOUR_EMAIL_ADDRESS:

List Password // URL
---- --------

followed by the name of each list you subscribe to, the password you use for that list, and the url to change your user options (or unsubscribe) for that list.

Frequently on the first of the month, I get an email or two from people who see these emails and rather than following the instructions and doing their own list maintenance, write to me and say “please unsubscribe me” or “please change my address to foo” or whatever, and I have a form letter that basically says “read the instructions and do it yourself”. But today I got a new variation:

It seems I have been added to this list by mistake. It looks as though this
address was found from the lugor mailing list. Please remove me from the
xcski mailing list.

My response was along the lines of “If you can’t tell the difference between a domain name and a list name, maybe Linux isn’t the OS for you.” Harsh, maybe, but hey, it amuses me and I get so few pleasures from mailing list hosting.

Why is it that a tech support problem doesn’t become an emergency until it’s most inconvenient?

I was quite literally standing up and collecting my wallet to go to lunch when I got approached by one of our support people and a fellow developer with a problem at a partner site. They described the problem and asked if I can log on to see if I can figure out the answer. I asked if it could wait until after lunch, and they said no because the system is going to be packed up and shipped to the evaluation center and it has to be working by then, and so we’ve got a 1 hour window to get it working.

So I go over and get Bob to log me on, and at first I’m lost. The subsystem that sends back the heart beat from one system to the other was the responsibility of a programmer who doesn’t work here any more. The log files don’t help much. But one thing I notice is that according to the logs, they’ve had this problem as far back as the logs go, about 14 days. Ok, it’s been a problem for 14 days, but evidently you can’t be bothered to fix it until there is 1 hour to go before an irrevokable deadline. Why is this my problem again?

I do some poking around a config file that I’ve had very little to do with in the past and I notice something glaring – the system is configured as [system] “2”, but it has another similar parameter set to an id of “1”. Ok, leaving aside the little question of why there are two parameters that control the same thing when one could probably be derived from the other, is this it? I change the second parameter to a 2 and restart it. And almost immediately start seeing heartbeats coming.

I’m out of there before they can find something else for me to work on, and the cafeteria doesn’t close for another 45 minutes. Yeah, me.