Technology: October 2004 Archives

(I promise I'll get back to ugly, nasty, brutal city politics shortly, but I need a break, and you probably do, too.)

Back in the early days of electronic calculators, there were books of calculator tricks -- calculate a certain formula and the result, when viewed upside down, spelled something. For example, on those primitive LED displays, 7734 upside down looked like H-E-double-hockey-sticks.

Programmers play similar tricks with numbers in hexadecimal notation. Hexadecimal notation is the base-16 representation of a number, unlike the base-10 notation you humans use, and in addition to 0 through 9, the letters A through F are used to represent 10 through 15, respectively. Hexadecimal notation is the usually the most convenient notation to represent the way data is stored in the memory of a computer. In the C programming language and its derivatives, hexadecimal numbers are differentiated from decimal numbers with a leading "0x". For example, 0x100 (hexadecimal) is 256 (decimal):

1 x 16² + 0 x 16¹ + 0 x 16⁰ = 2 x 10² + 5 x 10¹ + 6 x 10⁰

As a way to help debug software, programmers will create bogus values to be able to differentiate between uninitialized memory and memory initialized to 0. Any pattern will do, but it's more fun to use the letters of the hexadecimal digits to spell something. IBM engineers based in Austin programmed the AIX operating system to initialize memory to 0xDEADBEEF (must have been a Sooner that came up with that). Other examples (and they must be 8 digits long) are 0xBEEFCAFE and 0xf00dd00d (using 0 for O). Here are some examples, which also use decimal digits to represent numbers.

I recently came across a clever hexadecimal word that was unfamiliar to me. It's used as a domain name -- I found it while looking for information on how to stop referrer spam -- and in eight hex digits it sums up an important programming truth.

0xDECAFBAD

I couldn't agree more.

The site is worth a look around for those interested in creative ways to piece together different web tools to make interesting new things happen. And if you don't mind a couple of bad words, he has some sound advice for bloggers trying to figure out what to write about:

I haven’t been writing a lot here, but things have been percolating in my head. I’ve gone through phases of wanting this place to be a bit of a techie zine, I’ve been in a funk, and lately I’ve been telling myself that I should blog like no one’s watching....

The way I perceive this whole blogosphere working, long term, is for bloggers to read some Joseph Campbell and “Follow Your Bliss”. You could serve the whims of “traffic” for awhile, but if it’s not following your bliss, you’ll get tired of keeping up. But if you hook into your bliss, there’s bound to be traffic-a-plenty coming just to watch you do your own funky breakdance on that piece of cardboard you threw down on your domain name.

I hereby give myself permission to write about whatever the heck I feel like writing about. (But don't worry, I will still keep you up-to-date on Tulsa news, although lately that's less like dancing and more like a slog through the Slough of Despond.)