A Professional Technical Conversation

Me: I need to determine if an executable is in my path. So I use which...
Old Sk00l Unix Guru #1: Right.
Old Sk00l Unix Guru #2: Right.
Me: But I need to do it from a script, so I'm checking the exit code....
OSUG #1: Right.
OSUG #2: Right.
Me: And that works great on Linux. But on Solaris, it's 0 on both success and failure.
OSUG #1: Can't you just put it in backticks and grep the output?
Me: Well sure, I can. But it seems like such an old utility should have a way to return 'yes' or 'no'. What's the Old Sk00l UNIX Way to do this?

*all three characters pore over Solaris man page, which was last updated in 1992*

Me: I guess I'll do that. I just wanted to be sure that if I did the backtick and grep thing, someone isn't going to look at that later and say "what a n00b".
OSUG #1: You can write a comment that says "let me know if you have a better way".
OSUG #2: Or "to overcome braindead Solaris return code values".
Me: I guess leaving a comment about someone being braindead IS the Old Sk00l UNIX Way.

The Children Are Our Future

Number Two son (age 8) comes in to report that Number One son (age 10) is calling him stupid!

Number One son comes in holding a piece of paper:

Invention Idea #6

My office kitchen fridge has an incredible profusion of soda cans. (As an aside, I don't understand why: If you want it cold, just buy it from the machine right before you drink it. If you brought it from home to save money, you should be buying it in 2L bottles, not cans.)

Many cans are unlabeled, but some have a name scrawled on them, or some tape, or a business card stuck under the tab. However, these solutions have a couple problems. First, they only provide identification, not security. Second, some of these are kind of time-consuming. The tape, for instance, can't take less than 60-90 precious seconds during which you could be reading some hilarious emails forwarded from the secretary.

Thus my invention, which I call "Club Soda". You slip it on, snap it shut and club it with a tiny key. It would be personalized with your name via a tag or engraving or something. Security and identification in under 10 seconds. MSRP $4.99.

Garden Notes

Notes for next year:

• Plant only about 4 tomato plants, not 6.


• Same for the jalapeños.


• MORE green peppers. Or maybe they were just shaded by the tomatoes?


• Plant the tall things in the back. Which is to say, the tomatoes.


• Tomato cages have very little resistance to bending from being overloaded. Stake them.


• The Garden-Fresh Vegetable Cookbook has a trillion good ways to use all the results. (By the time I re-read this next year, I should know if they are actually yummy.)


• I will also know if making my own crushed tomatoes worked.


• Add snap peas, basil, cilantro and possibly watermelons.

Puzzle

Another hard one from the problem-a-day calendar.

My officemate and I discussed this one on-and-off throughout the day, drawing and redrawing many extra lines and triangles. We did finally solve it, but by a kind of questionable meta-method. Here's the basic idea:

Imagine blowing up the circle just a little bit. The line on the left can still be 12 units long. It will still be possible to have another line cut a chord 7 units long. And it will still be possible to have those two lines meet at a point. The angle they form will be different, though, and the value of x may be different. But the angle isn't a given and neither is the diameter of the circle. Therefore that problem is the same problem as this one. Since we know this puzzle has a unique solution, the value of x must actually be a constant and we can make that angle whatever we want. We will make it such that the chord is actually a diameter.

From that point the puzzle is easy and this method did yield the correct answer. The questionable part is assuming there was a unique solution. If we had come across this puzzle "in the wild" this wouldn't have been at all kosher. So how did the first person solve this puzzle? What's the real solution?

I Did It!

• Woooo! On 03/26/2007 I started at 259. Today I'm at 199.

  That's right, just 1/2 lb per week. Slow and steady catches the worm. In graphical form:

  My BMI is still technically overweight, though. Granted, BMI isn't a very good measure, but in this case I agree with the assessment and I'm going to go for 10 more lbs.



• I've only recently started using multiple colors of clay together. I have an irrational fear of "using up" the clay when I mix it, even though a pound of clay is like $1. However, a clay model gathers impossible-to-remove dust and small nicks. So I've finally bitten the more expensive bullet of switching to sculpey.

  A 4 year old of my acquaintance calls this "the treasure cat" and a 2 year old, also of my acquaintance, calls it "measure cat". (Also, any Cheshire Experts will notice right away the wrong color I didn't notice until too late.)



• I have a scrollsaw from way back but the blade broke and it turns out that that size is hard to find. Then last weekend I found a bandsaw at the flea market! After some tuning and tweaking, it's running great.

  Is this

  the first step on the road to this?

  Doubtful. But maybe!

I Just Won The Nobel Prize In Sandwiches

A BLT, only instead of mayonnaise, guacamole.

I wonder if egg salad could also benefit.

Contributing to the NERDliness of a Minor

Two minors, actually. A few months ago, I caved in to demands of my oldest two boys (10 and 8) to play D&D. They made me be the DM and they loved it. I did not really love it for several reasons:

1. Never played before. Any halfway game is annoying the first few times as you learn The System and what is and isn't important, etc.
2. Takes a lot of time to set up.
3. I feel like a real dork saying things like "leathern helm" or "dwarf mage".

So I didn't do it again. But that didn't make the demands stop. Finally, I told the 10 year old that I would play with them if he was the DM. Last night, we started that game.

Which brings me to the nerdliness. Playing D&D. Around the dining room table. While eating pizza, hot dogs and nachos. At least none of us has a neckbeard or obesity problem. Although one of us runs Linux. Oh and Mom brought in a sugary snack, plus we had our first game-based injoke.

Anyway, he actually did really, really well at it. I mean, we're wandering around without a clue in a very haphazard dungeon and he's giving hints pretty often ("do you want to check behind you?")...but he has the right attitude. He's confidently telling us what's what and taking our unanticipated actions completely in stride. Kudos, proto-NERD!

Happy Modification Of Most Sigificant Digit In Base 10 Representation Day!

I didn't even think to comment when the MSB in base 2 changed. What kind of a NERD am I?

Once my average catches up with the daily weigh-in, I'll be Officially At My (Original) Goal. I think I'm going to aim at another 10 lbs, though.

In other news, I've been messing around with Haskell, but I need a real programming project to really do something. I was thinking about this again.

I realized yesterday that it's not just hard but actually logically impossible to represent a mechanical object physically as a strict tree. Consider even just a triangle of beams. Two of them attach, making them children of the same parent (the joint). The third attaches to both, which is illegal.

A commenter suggested the netlist approach that electronic simulators take. The problem is that the netlist is a genome of the device. I have to be able to take a subset of the genome and swap it out for another piece that also has to drop in place. How does that work without leaving dangling "wires"? I could just leave them there for Nature to work out, but is that going to make success too infrequent for me to have patience for?

I think my algorithmic approach could work. But I haven't really worked it out. In any case, Haskell (or possibly better yet, Tcl or Lisp) is probably a good match. These languages already allow you to run data as code and treat code like data easily. Actually, now that I think about it, I'm not sure Haskell does that. What is that property even called?

Potpourri

• Continuing an Obsolete Technology theme from my last entry, I got a mechanical alarm clock at the flea market. All the parts worked, but it lost 5-10 minutes over a 12 hour period, at which point it would stop.

  I got a couple old-timey clock repair books at the library for tips on what to clean and/or adjust. Now it actually gains 2-3 minutes in 24 hours, but I recentered the little adjusty lever, so I should be able to make it keep good time. Unfortunately it still alarms 10 minutes before the set time. Also, it sounds like a fire alarm, which is maybe not the ideal thing to wake up only a single person at 5:30 am.

• Could have used this site years ago. Or is there a way to put MathML on Blogger now? If not, I guess I should learn LaTeX.

  

• While looking forward to LogiComix, I came across Uncle Petros and the Goldbach Conjecture. Fun, short read. I already knew about the Goldbach Conjecture, but the book gave me an idea for a possible disproof that probably doesn't work. First, the Conjecture: All even numbers > 2 can be expressed as the sum of two primes. One way to disprove this would be to find a number n such that no numbers from n to 2n are prime. There is already a theorem that proves that you can construct a "prime gap" of any size, so one of length n is no problem. The reason this doesn't quite work is that you also have to specify that the gap starts at n. Oh wait, it's even worse than that. There's a prime between n and 2n for all n. Pffff.
• You know what would be a killer app? Online WINE/Crossover. I could upload a Windows/OSX app and install it on a virtual machine and then interact with it via a generated Flash interface. I guess the only really hard part of this is the "generated Flash interface". Kind of like those programs that let me display on another computer (like X-Windows, but for all OSes) where the "another computer" is "a Flash app".