Tuesday Afternoon Surf Report

After being out of the water for almost one week, I was going surfing no matter what the conditions were. And today, they were small and junky, with a bit of wind added in for good measure. I made the best of the marginal conditions and had a good time getting back in the water again. It also looks like we'll be getting a bit of swell over the next few days.

Post Memorial Day Weekend Report

Last week was a bit of a traveling whirlwind for me. On Wednesday, I flew out to Philadelphia, PA for a sales presentation the following day. After the conclusion of our sales presentation, we got back on the plane and made our way back home the same day. Man, does air travel really suck now-a-days. Especially on the way back, when I sat next to a gentleman (and I use that term in the most loose sense possibe) who had yet to figure out what deodorant is used for. Talk about a long flight!

Getting home Thursday night, I had about 2 hours to pack my bags for a family trip out to Phoenix, AZ. We drove it, taking around 6 hours of drive time plus one stop each way - not too shabby when you take into account the little ones. As for Phoenix, well it was freaking hot. But I guess one should expect that in a DESERT. We watched my niece graduate, and then it was back on the road to San Diego, to salvage one day of the long weekend.

On Monday, we all went over to my parents' house and enjoyed some beautiful (not too hot, not too cold) weather, great food, and even better company. I was exhausted, but I guess that is what the work week is for - catching up with the weekend!

Tuesday Afternoon Surf Report

I almost decided to not go surfing today, due in large part to the cloudy, blustery weather we experienced yesterday. However, when 12:30 rolled around, I looked outside and the sun was burning through some low clouds. The wind was similarly low, and so I grabbed my CI single fin, and hoped for the best.

The waves were small (in the 3 foot range), but there were some nice shoulders to ride on, and I had three of the best waves I've had in a while. I'm damn glad I did go out, that is for sure. It looks like the conditions for the next few days will be the same, with a nice and juicy pulse (6 to 9 feet) coming in over the weekend from almost due west - perfect for North County! Keep your fingers crossed...

Multithreaded Programming w/ Delphi 5 on Windows XP

I have successfully solved a very nasty little programming problem which only appears to show up under Windows XP. First, a little backround: At my work, we provide loan calculation libraries to other parties, for use in their systems. One of our potential customers requested that we prove that our 32-bit Windows library is thread safe.

I knew that the library (written in Delphi 5) was currently not thread safe (it wasn't written by me!), but estimated that I could get it up to snuff in about a day or two. Before 'fixing' the library, I set out first of all to write a multithreaded client to prove that it was not thread safe. That way, I could then fix the DLL and then re-run the tests, hopefully proving that what was once broken was now fixed, etc.

Delphi is a great language to program in. It is object oriented, with full support for all the OOP buzzwords like: polymorphism, information hiding, etc. Couple that with a great support library and a lightning quick compiler, and you have a very great combination. So, I quickly whipped up an application that spawns 4 worker threads, each of which compute a different loan 4000 times. Each time through the calculation loop, it checks to see if the results returned from the thread-unsafe library have changed from the correct, base line results computed in a single thread at application initialization.

As expected, the app crashes hard with EInvalidPointer exceptions, etc. It is ugly indeed. So, I then go into the DLL and strategically place some critical sections to protect the vulnerable areas, and then run the multithreaded test again. And it still doesn't work. However, it DOES work on Windows boxes of the flavors 98 and 2000. Very odd.

It is hear that my 40 days in the programming wilderness begins. I write a second, simpler console based multithreaded client in the thoughts that perhaps the vcl thread was creating problems. That didn't do the trick. I simplified the test apps as much as possible, with no luck.

After three days of pounding my head against this programming brick wall, scouring the net via Google, I stumbled upon a reference to a global variable names IsMultiThread, supposedly set up by Delphi in System.pas. This variable is supposed to be automatically set to true whenever you use Delphi's TThread object, and one would guess that it should also be set for DLL projects. I decided to explicitly set this variable to True in the initialization section of the DLL, as well as in the test applications startup.

EUREKA! The problem was solved, and I was able to rest over the weekend. Except that 2 out of 3 kids were sick, but that is an entirely different saga. So, the moral of the story is that when writing a multithreaded library or application in Delphi 5, just go ahead and explicitly set IsMultiThread := true. I hope this post can help someone avoid the same problem again!

Tuesday Lunch Break Surf Report

Driving into work today, I went along the 101 and saw some very nice looking waves breaking all along North Country. While kicking myself for not getting out on a Dawn Patrol, I hoped that the waves and conditions would remain consisten, at least through my lunch.

Unfortunately, it wasn't to be. The wind kicked up, and the tide was changing during my lunch break surf, resulting in extremely choppy and mixed up waves. It appears as if we may be getting a nice little bump in the South swell near the end of the week, but it may be coming along with some inclement weather as well. d'oh!