February 2011 | Page 2 of 3 | The Old New Thing

WM_NCHITTEST is for hit-testing, and hit-testing can happen for reasons other than the mouse being over your window

Raymond ChenFebruary 18, 2011Feb 18, 201102/18/11

The WM_NCHITTEST message is sent to your window in order determine what part of the window corresponds to a particular point. The most common reason for this is that the mouse is over your window. Although WM_NCHITTEST triggers most often for mouse activity, that is not the only reason why somebody might want to ask, "W

What is the highest numerical resource ID permitted by Win32?

Raymond ChenFebruary 17, 2011Feb 17, 201102/17/11

A customer asked the following question: What is the maximum legal value of a resource identifier? Functions like LoadString take a UINT as the resource ID, which suggests a full 32-bit range, but in practice, most resource IDs appear to be in the 16-bit range. Is there any particular history/precedent for avoiding large numbers as res

What is the difference between a directory and a folder?

Raymond ChenFebruary 16, 2011Feb 16, 201102/16/11

Windows 95 introduced Windows Explorer and along with it the term folder. What is the relationship between folders and directories? Some people believe that Windows 95 renamed directories to folders, but it's actually more than that. Windows Explorer lets you view folders, which are containers in the shell namespace. Directories a

Don't mention the war. I mentioned it once, but I think I got away with it all right (Episode 2)

Raymond ChenFebruary 15, 2011Feb 15, 201102/15/11

In preparation for the 2012 Olympic Games in London, the official UK tourism bureau produced tips for dealing with people from other countries.

Window message parameters do not come with metaphysical certitude

Raymond ChenFebruary 15, 2011Feb 15, 201102/15/11

The MSDN documentation for window messages describes what each of the parameters means, but just because it means something doesn't mean that it is that something; it merely means it. But you knew this already. If you have a window handle, you can send it whatever message you like, with whatever parameters you like, even if those parameters c

What happens when you email the people in the I'm a PC commercial?

Raymond ChenFebruary 14, 2011Feb 14, 201102/14/11

In 2008, the first I'm a PC ad aired, opening with Sean Siler doing an impression of John Hodgman portraying a PC, and continuing with montage of people proudly announcing, "I'm a PC!" Accompanying the first four people to appear on screen are email addresses. The addresses are live (or at least they were when the campaign launched), and if

Any intelligent human being

Raymond ChenFebruary 11, 2011Feb 11, 201102/11/11

The story of The Best reminded me of a classmate from school who was inordinately fond of the phrase any intelligent human being. For example, our classmate would say, "Any intelligent human being would do X" or "It's obvious to any intelligent human being that Y." (I often—but not always—consider myself to be an intelli

How do specify that a shortcut should not be promoted as newly-installed on the Start menu?

Raymond ChenFebruary 11, 2011Feb 11, 201102/11/11

Windows XP employed a number of heuristics to determine which Start menu shortcuts should be promoted when an application is newly-installed. But what if those heuristics end up guessing wrong? You can set the System.AppUserModel.ExcludeFromShowInNewInstall property to VARIANT_TRUE to tell the Start menu

Psychic debugging: Because of course when something doesn't work, it's because the program was sabotaged from above

Raymond ChenFebruary 10, 2011Feb 10, 201102/10/11

When something stops working, you begin developing theories for why it doesn't work, and normally, you start with simple theories that involve things close to you, and only after you exhaust those possibilities do you expand your scope. Typically, you don't consider that there is a global conspiracy against you, or at least that's not usuall

Why does SHGetKnownFolderPath return E_FAIL for a known folder?

Raymond ChenFebruary 9, 2011Feb 9, 201102/9/11

A customer reported having problems with the SHGetKnownFolderPath function. I've left in the red herrings. On Windows 7, I'm trying to retrieve the Internet folder with the following code: The call always fails with E_FAIL. What am I doing wrong? I tried passing NULL as the token, but that didn't help. The re

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