So the new place to bookmark is boyet.com, and the new feed to subscribe to is here.

This original website will remain in stasis, with all the action happening on the new blog. See you over there!

Email me if you have comments about this article.

What you do is to create an account (it makes it easier later on), and then tell it what music you like by specifying an artist, a band, an album, or a song. From that, and from some metadata on what the music is all about, Pandora then creates your own personal "radio station" selecting and playing songs that are similar in vein to the information you provided.

Easy enough. I created a radio station based on Massive Attack and another on Thievery Corporation as an experiment to see what it could do. Blimey, it ain't 'arf good at it. The music it's been playing has been very interesting and some of it makes me pause to see what's playing. This is supposed to be background music, dammit, to help me work, and instead I'm checking to see what's playing.

Worse than that, some of it I like so much, I end up buying the album. Hence the blog.

Every time this happens, I'm spending another $10 at Amazon's MP3 store. Help!

Here's some examples of what I've purchased since listening to Pandora using these two "radio stations". None of these artists I'd heard of before, but I certainly like what I've bought very much.

• Freaks & Icons by dZihan& Kamien
• Reflections by Paul van Dyk
• Vertigo by Groove Armada
• Far Away Trains Passing By by Ulrich Schnauss
• A Heap of Broken Images by Blue Sky Black Death

I will note in passing that these artists are all British or European. Hmm.

Anyway, I certainly recommend you trying Pandora if you want to spend a nice chunk of cash if you want to want to listen to music that you like.

UPDATE: One of my readers in Germany (hi, Joe!) tells me that Pandora is US-only at this point. Their license agreement does not extend outside the US. Bummer.

Email me if you have comments about this article.

Being as I'm yer actual CTO with DevExpress, one of if not the biggest third-party VCL component vendors, I get to play with the new toy before many others. Several times a month, in fact. Betas are popping out like rabbits in a lush green field. To say Delphi R&D have been going through smacking bugs in the bug reporting system like Orkin does with the ants in my garden is an understatement.

Only a couple of days ago, some of us were asked to discuss Tiburón publicly after we'd used it for a while. Well, "a while" for me is a couple of recent evenings, playing with it using my particular codebases.

I duped a nice clean Windows XP virtual machine (VM) and installed the latest beta on it. OK, it was a VM and, to alleciate that a little, I do have a fast four-core 64-bit monster of a machine, but the install was nevertheless nice and rapid. Delphi 2007 was a little slothful, shall we say, about installing, but Tiburón was decidedly snappy. So much so, that your intrepid reporter didn't even make a note of how quick it was to install. Doh! I did some other simple work that was on my plate and the next thing I noticed was the install was complete. In the order of 10 minutes, perhaps. Now, agreed I didn't install the C++Builder personality, nor was there any help install with this particular beta, but this was certainly a major leap in the right direction.

I then loaded my venerable EZDSL library into the IDE and recompiled it.

One hint, no errors, and that was it. It was really boring. Honestly, I was flexing my mental and authorial muscles ready to desk check my string usage, modify it, and then talk at length about it, but there was nothing to do. Damn.

So, apart from adding another compiler option block for Delphi 2009 ($IFDEF VER200, don'tcha know), all I had to do was remove the word "packed" from a single record type definition. To be honest I don't think even that was needed, so I've got a query on the internal newsgroups about it.

Well then, er, sorry, but there's no big story about burning the midnight oil on this one. EZDSL works with Delphi 1 through Delphi 2009, at least in my VM, without very much ado at all.

The test programs though, gaak, what a mess; compiler warnings all over the place. To be expected somewhat since I'd been mixing short and long strings willy-nilly in there, so next time I'll talk about how I fixed all that. And of course, I'll be porting my book's code as well, so stay tuned.

Email me if you have comments about this article.

No matter how I look at this, it has scam writ large all over it, even on the front.

1. The postage was paid for in Florida, but the company is in Missouri.
2. It has a big red band with "Final Notice" written on it. Funny that I don't recall receiving any prior notice.
3. The company name, "Dealers Warranty" is to make me think this is part of the network of dealers for my car. Except I have two cars, of two different makes.
4. Nice random GUID-like customer number there. Maybe the "-07" means July?

Turning to the back now. Man, it's looking bad for me. "Final" is all over the place, in red again, and to make it more urgent, it mentions 48 hours and 20% discount. Twice. There's a special code too! Oh, noes! I'd better do something right now. Except...

1. 48 hours from when exactly? There is no date. The postcard was bulk mailed from Florida, taking, what, 3 or 4 days to arrive?
2. Why do they want the VIN#? Surely they know, since they're part of the dealer network? Can't they track it from my (random) customer number?
3. I've been pre-selected for this exclusive program, so you'd imagine they'd know something about me, like what I drive. Er, that would be no.
4. In short, there is absolutely no mention of the actual car the final notice is all about. Zero, nada, zilch. As I mentioned I have two, neither of which is anywhere near falling out of warranty. So which car is this for again?
5. And I'm supposed to phone at certain times, CST, Central Standard Time. But it's summer and they're presumably in daylight savings time now, aren't they? Why not just put CT? Or is the postcard so generic they could post it in the winter?

So, all in all, this is one postcard I won't be replying to. (More.)

UPDATE: These types of car warranty scam artists are prone to phoning you as well. All you get is a recorded message with "Press 1 to speak to an operator or 2 to be removed from the list". Yeah, right. Dream on. The thing is, there is no list. These are robocalls from some computer system. They don't know who they're calling because they're just calling all numbers in rotation. In fact, they don't know if it's a landline (we're on the Do Not Call list, but they don't have it and wouldn't pay attention to it if they did) or a cell phone (that's illegal).

Here's a list of numbers from which I've been phoned about car warrenty scams. I'd add to it as and when I get called. Since they're paying for the call I generally listen to the entire message.

1. 323 581 3046  (06-Aug)
2. 805 985 4838  (11-Aug)
3. 304 862 3407  (14-Aug)
4. 843 248 9071  (15-Aug)
5. 804 417 1862  (22-Aug)
6. 207 674 2609  (29-Aug)

Email me if you have comments about this article.

That's all very well, but you should practice some what I may call prophylactic procedures first.

Take a look at the code you're about to use. Do you understand it? Is it using classes, methods, properties you've not met before? Read up on them. Put it into a test harness and run it. Does it run as you'd expect? Think of failure cases, and try them out: does it behave?

But most of all: read the code and understand it.

Let's take an example. There's a blog I read occasionally, found though Jeff Duntemann, hosted by Michael Covington. Very interesting blog, especially with regard to astronomy photos. He takes some stunning photos of planets, stars, clusters, galaxies. Magic.

I wish however he'd keep away from programming. Here's a very recent example: finding the speed of the CPU using C# and WMI (Windows Management Instrumentation).

I learnt a whole bunch about WMI when I worked at Configuresoft, and in those days I learned how flaky it could be (I dare say things have improved since then). In essence it's an interface to a whole bunch of configuration options and values from the current or perhaps remote system. It runs as a service that you can stop or disable.

So Covington has this code, the idea for which was obtained from the internet, I'm guessing.

    static double? CpuGHz() {
      double? GHz = null;
      try {
        ManagementClass mc = new ManagementClass("Win32_Processor");
        foreach (ManagementObject mo in mc.GetInstances()) {
          GHz = 0.001 *
             Int16.Parse(mo.Properties["CurrentClockSpeed"].Value.ToString());
          break;
        }
      }
      catch {
        // do nothing
      }
      return GHz;
    }

As soon as I read the piece and the code red flags appeared.

The first was the blithe justification for the empty catch block. This is just bad coding practice. You should never have an empty catch block because it will catch everything, not just exceptions form your own code. Even very bad exceptions that really say "shut down now, abandon all hope, Buster" will be caught and tossed aside. Equally as bad is a catch block that catches objects of type Exception. Nuts to that: you should catch only those exceptions you are willing to catch and process, If you are not willing to handle any exceptions then don't catch them, let something else further up the food chain worry about handling them. If you find out later that there's some exception type you can catch and, say, ignore, then modify the code to do so. Ignoring all exceptions is never "precisely the desired action".

So I decided to play around with the code. First I paused the WMI service. I then added a couple of lines to the catch block to actually catch the damn exception and print it out. The call to create the ManagementClass takes a long time to execute now, but eventually it fails with a System.Runtime.InteropServices.COMException. The message is "Server execution failed (Exception from HRESULT: 0x80080005 (CO_E_SERVER_EXEC_FAILURE))". So now I know what to put in my catch block should the code be run on a system without the WMI service running. (Some other research revealed that System.Management.ManagementException could be thrown too.)

Habing done thnis research I decided that a "low-level" method such as this shouldn't be in the business of catching anything, expecially COMExceptions. So I took out the try..catch.

The next red flag is just as visible, since Covington brings attention to it as well. The result value of the GetInstances() call is some kind of enumerable collection that does not indexing defined on it, so you have to use an enumerator. Covington just breaks after the first item, but my immediate reaction was are there any more items in this collection. What is so special about the first?

So I altered the code to print out all of the items. As it happened there was only one. I did wonder, since I'm using a quad core, whether there might be 4 items in this collection. Guess not.

Next up is the requirement to convert the Value property of the CurrentClockSpeed value to a string and then parse it back into an integer. Yuk. Let's write a little code to check what type Value is in this instance, ah, UInt32. (In fact, browsing through the MSDN documentation for WMI reveals the same type for this property.) Cool: we can get rid of the ToString() and Parse() calls.

The next red flag is more subtle, but it's something I've learned from the school of hard knocks to watch out for. If there's a class being instantiated I don't know, especially when it's going to be discarded pretty much immediately, I go check to see whether it's implementing IDisposable. If it is, I should use the using() construct in C# to ensure that Dispose is called.

With Refactor! Pro, this check is really simple. Put the caret on the new object being created, press the Refactor key, and look to see if the "Introduce Using Statement" option is present. If it is, select it.

So, after that little bit of research and experimentation, here's a better (more efficient, more robust, won't knife you in the back) routine to get the current CPU speed.

using System;
using System.Management;

namespace CpuSpeed {
  class Program {

    static double? GetCpuSpeedInGHz() {
      double? GHz = null;
      using (ManagementClass mc = new ManagementClass("Win32_Processor")) {
        foreach (ManagementObject mo in mc.GetInstances()) {
          GHz = 0.001 * (UInt32) mo.Properties["CurrentClockSpeed"].Value;
          break;
        }
      }
      return GHz;
    }

    static void Main(string[] args) {
      Console.WriteLine("The current CPU speed is {0}", (GetCpuSpeedInGHz() ?? -1.0).ToString());
      Console.ReadLine();
    }
  }
}

My point here is you really should make some effort to sanitize code you download from the internet. This is not an NIH attitude, but a recognition that you really don't know how experienced the developer at the other end of the URL really is.

Email me if you have comments about this article.