The Old New Thing

Undecorating names to see why a function can’t be found

December 29, 2008 Dec 29, 2008 12/29/08
Raymond Chen
Here's a problem inspired by actual events. When I build my project, it compiles fine, but it fails during the link step with an unresolved external: program.obj : error LNK2001: unresolved external symbol "public: virtual wchar_t const * __thiscall UILibrary::PushButton::GetName(class UILibrary::StringHolder * *)" (?GetName@PushButton@...

Then again, sometimes the improvement is merely incremental

December 25, 2008 Dec 25, 2008 12/25/08
Raymond Chen
Several years ago, the security department sent out a company-wide memo: Over the next few months, we will be upgrading the card readers on all of our major campuses. The old card readers show a solid red light when the door is locked, whereas the new card readers show a blinking red light. Aw-right, a blinking light. Now we're cookin' with...

Foiled by my withered hand

December 24, 2008 Dec 24, 2008 12/24/08
Raymond Chen
A few years ago, some email was sent out to the product team asking for a volunteer hand model to demonstrate how to open the Windows Vista box. Alas, I withdrew myself from consideration due to my withered hand...

Why isn’t there a SendThreadMessage function?

December 23, 2008 Dec 23, 2008 12/23/08
Raymond Chen
Here's an interesting customer question: Windows has and . It also has but no . Why isn't there a function? Am I forced to simulate it with an event? What would this imaginary function do? Recall that delivers the message directly to the window procedure; the message pump never sees it. The imaginary function would have to deliver ...

On 64-bit Windows, 32-bit programs run in an emulation layer, and if you don’t like that, then don’t use the emulator

December 22, 2008 Dec 22, 2008 12/22/08
Raymond Chen
On 64-bit Windows, 32-bit programs run in an emulation layer. This emulation layer simulates the x86 architecture, virtualizing the CPU, the file system, the registry, the environment variables, the system information functions, all that stuff. If a 32-bit program tries to look at the system, it will see a 32-bit system. For example, if the ...

What is the mysterious fourth message box button?

December 19, 2008 Dec 19, 2008 12/19/08
Raymond Chen
When you call the MessageBox function, you pass flags specifying which of a fixed set of button patterns you want (for example, Yes/No and OK/Cancel) and which button you want to be the default (MB_DEFBUTTON1 through MB_DEFBUTTON4.) Wait a second. What's with this MB_DEFBUTTON4? None of the button patterns are four-button patterns. The ...

How do I obtain the computer manufacturer’s name?

December 18, 2008 Dec 18, 2008 12/18/08
Raymond Chen
One customer wanted a way to determine the name of the computer manufacturer. For example, they wanted to make some function call and get back "IBM" or "Compaq" or "Dell". I don't know why they wanted this information, and for the moment, I don't care. And of course, when you're looking for information, you don't search MSDN; that's for ...