The debugger lied to you because the CPU was still juggling data in the air

A colleague was studying a very strange failure, which I’ve simplified for expository purpose. The component in question has the following basic shape, ignoring error checking: // This is a multithreaded object class Foo { public: void BeginUpdate(); void EndUpdate(); // These methods can be called at any time int GetSomething(int x); // These methods…


Various ways of performing an operation asynchronously after a delay

Okay, if you have a UI thread that pumps messages, then the easiest way to perform an operation after a delay is to set a timer. But let’s say you don’t have a UI thread that you can count on. One method is to burn a thread: #define ACTIONDELAY (30 * 60 * 1000) //…


Why are there both FIND and FINDSTR programs, with unrelated feature sets?

Jonathan wonders why we have both find and findstr, and furthermore, why the two programs have unrelated features. The find program supports UTF-16, which findstr doesn’t; on the other hand, the findstr program supports regular expressions, which find does not. The reason why their feature sets are unrelated is that the two programs are unrelated….


Security vulnerability reports as a way to establish your l33t kr3|)z

There is an entire subculture of l33t l4x0rs who occasionally pop into our world, and as such have to adapt their communication style to match their audience. Sometimes the adaptation is incomplete. I have appended a file which exploits a vulnerability in XYZ version N.M. The result is a denial of service. The perl…


Puzzling triple rainbow clearly identifies location of pot of gold

I noted to some friends that the weather forecast for Seattle two weekends ago called for rain on Friday, rain on Saturday, and rain on Sunday. But at least on Monday, the forecast was not for rain. It was for heavy rain. One of the consequences of Seattle’s annual Rain Festival (runs from January 1…


How does the window manager decide where to place a newly-created window?

Amit wonders how Windows chooses where to place a newly-opened window on a multiple-monitor system and gives as an example an application whose monitor choice appears inconsistent. The easy part is if the application specifies where it wants the window to be. In that case, the window is placed at the requested location. How the…


The Hater’s Guide to the Williams-Sonoma Catalog

Today is the traditional start of the holiday shopping season in the United States. If you are thinking of getting something from Williams-Sonoma, Drew Margary has selected a few items of note for your consideration (NSFW: language). (It cracks me up that the model is using the batter dispenser which “measures out uniform circles” to…


When studying performance, you need to watch out not only for performance degradation, but also unexpected performance improvement

In addition to specific performance tests run by individual feature teams, Windows has a suite of automated performance tests operated by the performance team, and the results are collated across a lot of metrics. When a number is out of the ordinary, the test results are flagged for further investigation. The obvious thing that the…


The resource compiler will helpfully add window styles for you, but if you’re building a dialog template yourself, you don’t get that help

A customer was having trouble with nested dialogs. They were doing something very similar to a property sheet, with a main frame dialog, and then a collection of child dialogs that take turns appearing inside the frame dialog based on what the user is doing. The customer found that if they created the child dialogs…