Means to an end

​I used to think that knowing the ropes at the kernel level was not only cool, but it had value on its own. Very few people could debug a system crash, so it seemed like rocket science. Not for long!

One day, at a party, I was talking with a friend, the usual topics over a drink: politics, gossip, how's work. They were having trouble connecting two applications, of which one was running on Coral-11 and the other was part of an Alenia system. What?

Anyway, I offered to help and the next weekend I went to his workplace, the Romanian Air Traffic Services Administration (ROMATSA). They were working on an interim solution to pair the flight data (hosted on Coral) with the radar tracks managed on a UNIX platform.

In theory, I knew what real-time means and I knew how to write a driver, but it was like doing calculus in school - you learn the means without having much understanding of the ends.

Real-time processing does not not have to be fast, just fast enough. Get it done before the next set of data comes. And if not, and there is no way to get a break, just drop it, don't keep queueing obsolete data. It's much easier today if you chose the proper middleware.

That was a very basic application, nothing fancy, just receiving an aircraft transponder code and using a lookup table to retrieve the flight id and send it back, such that the controller would have not only the aircraft position, speed and altitude, but also know which flight was that and where was going. All I had to do was to decouple the I/O part from the original application, such that it could run uninterrupted while reading/writing the registers and buffer properly the requests. Debugging was a bit painful, though; they didn't have a lab for testing the code, just the operational system, so I had to work odd hours when the traffic was low.

It all worked fine in the end and I was given not only the visitors tour in the Ops room, but also the chance to work for them. They were building a team of engineers to support the management of an increasingly complex air traffic.

I rarely let things pass by me.