The principle of "garbage in, garbage out" applies to Unicode collation. If you hand it a meaningless string and ask to compare it to another meaningless string, you get meaningless results. I am not a Unicode expert; I just play one on the web. A real Unicode expert is Michael Kaplan, whose explanation of how comparing invalid Unicode ...
Random number generation is hard. That's why you should leave it to the experts. But even if you choose a good random number generator, you still have to seed it properly. The best random number generator in the world isn't very useful if people can guess the seed. That's why seeding the random number generator with the current time is...
If the "Group similar taskbar buttons" box is checked (default) and space starts to get tight on the taskbar, then then the taskbar will group together buttons represending windows from the same program and give them a common name. Where does this common name come from? The name for grouped taskbar buttons comes from the version resource of ...
One of the big advantages of managed code is that you don't have to worry about managing object lifetimes. Here's an example of some unmanaged code that tries to manage reference counts and doesn't quite get it right. Even a seemingly-simple function has a reference-counting bug. The point of this function is to take a (pointer to) a variable t...
The regular expression *? operator means "Match as few characters as necessary to make this pattern succeed." But look at what happens when you mix it up a bit: This pattern matches a quoted string containing no embedded quotes. This works because the first quotation mark starts the string, the .*? gobbles up everything in between, and th...
I've seen people using the following cheat when forced to implement an enumerator: Why create a separate enumerator object when you can just be your own enumerator? It's so much easier. And it's wrong. Consider what happens if two people try to enumerate your formats at the same time: The two enumerators are really the same enumerator, so o...
All these functions have an optional LPSECURITY_ATTRIBUTES parameter, for which everybody just passes NULL, thereby obtaining the default security descriptor. But what is the default security descriptor? Of course, the place to start is MSDN, in the section titled Security Descriptors for New Objects. It says that the default DACL comes from ...
Warning: .NET content ahead! Yesterday, Brad Abrams noted that Char.IsLetter() matches more than just "A" through "Z". What people might not realize is that Char.IsDigit() matches more than just "0" through "9". Valid digits are members of the following category in UnicodeCategory: DecimalDigitNumber. But what exactly is a DecimalDigitNumber? ...
How the design of the C++ language subverts thread safety.
If you want to display modal UI, you need to disable the owner and enable the modal child, and then reverse the procedure when the modal child is finished. And if you do it wrong, focus will get all messed up. If you are finished with a modal dialog, your temptation would be to clean up in the following order: But if you do that, you'll...
