dspector is a longtime Web and Windows programmer. Besides doing software engineering, his hobbies include working for civil rights for blind and visually impaired people, teaching deep meditation, playing Go, and contributing to Wikipedia.

Global variables are a fact of life. Although global variables are technically never necessary, particularly in PHP programs that use object-oriented design, they often make programs easier to read and easier to write. There are definitely situations in which they are reasonable and appropriate: resources or handles returned from API calls that are used in many functions, frequently-used arguments passed in via GET or POST, and very long strings used in cryptological protocols are some cases that come to mind.

The problem I have with global variables in PHP is that they work the opposite way they do in other languages: they are declared in each function, instead of at file level. This is about as verbose and difficult to maintain as passing each global variable used by a function in its argument list. Argument lists (or "global" statements) become longer, and must change wherever needed when a new global variable is added to the program.

I've spent hours debugging problems caused by omitting a variable from a "global" statement. I consider it a crime to have robbed me of my time like this. And no, I can't make do by using the special $GLOBALS array. That syntax is even worse, because it puts the syntactic burden on every reference to a global variable. The syntactic burden should only be in one place: at a single declaration of the global variable at file level, as it is in most other programming languages.

Here is my solution: a way in PHP to declare global variables at file level and have them automatically be available inside functions, using a modicum of elegance (although this method does incur the expense of importing all declared global variables into each function, whether they are referenced or not). Here is the usage, given by example:

If you want the global declaration to include an initial value, you can write it like this:

Here's all the code you need to implement this technique; include this code at the start of each PHP file:

Netminder is one of the Site Administrators at Experts Exchange.

We'll be the first to admit it: we don't do games much. Except for the ones that came with the operating system, our experience with them is limited to kibbitzing over our better half's shoulder once in a while -- and even then, we don't claim to know much about what's going on. We did once fiddle around with Myst, and a four-year-old of our acquaintance was a whiz when it came to playing Doom -- but for whatever reason, we never got into them much.

But three stories caught our eye last week, so we thought we would pass them along, if only because we know we have not given the Gamers their due. We caught some flak back in January when we announced the Expert of the Year awards because the Game Emulators topic area was included. Memo to Experts: Game Emulators was 32nd on the list of TAs by page views, right below C++ Programming, and right above Microsoft Excel.

The first story says that the Quad Core computers will be useless for games. The main problem, developers say, is that the performance isn't very scalable. That's something the database and programming folks have been dealing forever, but for the gaming developers, the notion of introducing more cores is also a red flag because it means more bugs. Since the market for games is dependent on new products fairly frequently (people can only figure out the tricks and win the game so many times before they are bored), optimizing for four cores will hurt, rather than help.

The second story is about everyone's favorite whipping boy: Microsoft's Vista, and in this particular instance, it is Microsoft that is delivering the bad news: Games will run ten to fifteen per cent slower using Vista, compared to Windows XP. The rap is on the 3-D desktop API -- which Microsoft has been telling developers will work up to four times faster.

Finally -- and this is only marginally related -- PCPro/UK has found the fastest PC on the market: the Apple Mac Pro with the Quad Core Intel processor. Now, before all you Mac fans start needling all of us who use PCs, that's the good news. The bad news: you have to dump the OS X operating system and use Windows XP. Still, given the price tag of the basic model, it's worth a second look.

Especially if you plan to buy new Desperate Housewives game as an early Christmas present to yourself.

ericpete is the editor of the Experts Exchange newsletter. He considers the main benefit to doing that job to be the opportunity to write -- something he has done professionally since he was a young boy.

My father is one of my favorite writers. He spent most of his early life shaping his craft before he finally bought a couple of small newspapers where he could write what he wanted without worrying about what his boss might think. He was passionate without being strident, compelling and not overbearing, witty without stretching to make a joke. But his most remarkable attribute, as a reporter, was in his ability to get to the heart of a story in very few words.

We didn't get a lot of advice from him in advance, which was probably a good thing; the surest way to get children to do things is to tell them not to do them, right? So his counsel was generally limited to brief comments after the fact, when they would have the most impact.

One such piece of advice: Never get into a pissing contest with a skunk.

So what does this have to do with the digital world we live in? Well, a few weeks ago we happened to pick up the Kansas City Star's sports section. In it, there was a column written by Jason Whitlock, in which he called out one of his colleagues, Scoop Jackson of ESPN. A decade or so ago, newspaper columnists didn't do that kind of thing; they might disagree, but they would worry about their own point of view, and making their own case.

Not that we mind the ongoing war of words; there's something deliciously gratifying about watching two oversized egos going at it like seven-year-olds on a playground. In the days -- when one had to pick up a newspaper and get one's fingers a little discolored -- we never would have been able to read the literate but pretentious Whitlock, and wouldn't have bothered with the self-serving but relevant Jackson. It's almost as entertaining as hearing about Paris Hilton's cell-phone.

Another piece of advise from Pop: Report the story, don't become the story.

But that's what the Internet has done, although there's no question that the money and exposure of television set the table. Forget all the angst about "Web 2.0" -- mass communication changed fifty years ago, when a lot of newspapers switched to offset printing. Bigger newspapers had an expensive piece of equipment on which they wanted a return on investment (a press), and smaller newspapers couldn't justify the expense of equipment that ran for only a few hours a week -- and all of a sudden, anyone with a carbon ribbon typewriter and a camera could start his own paper.

The Internet has taken it one step further. Anyone can have a website, anyone can set up a blog, and anyone can have his say. What we fear, though, is that if everyone is talking, it means that no one is listening. Freedom of speech -- the right to say what you want about your political beliefs, or about your religious beliefs -- is not the same as the right to be heard, and it certainly doesn't mean that you have anything valuable to say. "Everybody's talkin' at me," Fred Neil wrote, "I don't hear a word they're saying."

And it's not just your everyday blogger -- even the world's self-proclaimed "most respected name in journalism" is susceptible: the lead story the day Katie Couric took over the anchor desk for CBS News was Katie Couric taking over the anchor desk at CBS News. But that's what we have done to ourselves; our little corner of the universe is now the center of it.

I got an email the other day from someone asking me if they should upgrade to Vista when it comes out. Now, I don't claim to know all the ins and outs of Vista, but I will tell you this: I don't like upgrading just because. My computer has Windows XP on it, but that's because my other half bought it for me early this year, and that's what came on it; my old one was dying, but I was perfectly happy with Windows98.

So with that in mind, here's what I can tell you about Vista. The interface reminds me more of a Mac than it does Windows XP. It's very futuristic, and very slick. Along with that, Microsoft is completely reworking Internet Explorer, Windows Movie Maker and Media Center. But there are a few downsides too. For one, you need to have a fairly new computer if you plan on upgrading, because Vista's hardware requirements are pretty steep. Second, at this point, Microsoft wants you to use their security system, which, if you have been reading this column for a while, you know is... well ... silly. Personally, I want at least two different programs monitoring my computer, because with all the spyware, viruses and stuff going around, no one program ever seems to get them all. At the very least, I want a choice.

I expect that EE will be adding a Windows Vista topic area pretty soon, and most of the Experts at EE know a lot more about it than I do, so be patient -- it will be there. But I will tell you this: I probably won't move to Vista until I absolutely have to.

The newsletter had an item a while back about how Yahoo was coming out with a beta version of its email that had an Outlook Express type of interface. Now Hotmail is doing the same kind of thing. It has a preview pane and autocomplete for addresses in your address book, and offers 2 Gb of storage.

Sophos -- my favorite site for information about threats, by the way -- has a new paper out on what is the biggest threat, in my book, to your computer: having it become a zombie. The paper has a really good description of how they are created, how they have evolved, and what you can do about them. The last numbers I saw suggested that something like 5 million computers are being controlled by bots, so it's serious. If you're interested, Symantec's report on security threats in the first half of 2006 is also available.