Showing archive results for 2012

Every few years, the building maintenance people have to perform tests on the elevators to ensure they meet safety regulations. And the real estate department sends out the usual notice informing the building occupants that the elevators in the building will be taken out of service at various times during the day. They were kind enough to include...

Ian Boyd wants to know why the specific value of 500ms was chosen as the edit delay in Windows Explorer. Because it's your double-click time. Since the double-click action (execute) is not an extension of the single-click action (edit), Explorer (and more generally, list view) waits for the double-click timeout before entering edit mode so it c...

In a discussion of how real-mode Windows walked stacks, commenter Matt wonders about fixing jumps in the rest of the code to the discarded functions. I noted in the original article that "there are multiple parts to the solution" and that stack-walking was just one piece. Today, we'll look at another piece: Inter-segment fixups. Recall that ...

One quirk of nested dialogs lies in what happens when the user presses Enter to invoke the default pushbutton: The resulting message goes to the top-level dialog, even if the default pushbutton belongs to a sub-dialog. Why doesn't it send the to the parent of the default pushbutton? I mean, the dialog manager knows the handle of the button, so...

Today is the last day of school in Seattle public school. My friend the seventh-grade teacher told me that students count down to the last day of school in a rather unusual way. Some people might count the number of calendar days until the end of school. For example, if there are 35 days between today and the last day of school, we say that it's 3...

The extended style (known in dialog templates as ) instructs the dialog manager that the dialog's children should be promoted into the dialog's parent. This is easier to explain in pictures than in text. Given the following window hierarchy: The result of the extended style being set is that the children of B are treated as if they were di...

When you build a dialog, either from a template or by explicitly calling , one of the pieces of information about each control is a child window identifier. And it's probably in your best interest to make sure two controls on the dialog don't have the same ID number. Of course, one consequence of giving two control the same ID number is that the ...

An anonymous commenter was curious about how the function arrived at its strange name, what the purpose of the third parameter is, and why it is inconsistent between Windows 95 and Windows NT. The sense of word "random" here is hacker slang rather than its formal probabilistic definition, specifically sense 2: "Assorted, undistin...

The Corporate Citizenship Tools; Microsoft Local Language Program Web site contains a map of the world, coded by region. There was a bug on the map. See if you can spot it: After I pointed out the error, they fixed the map on their Web page, so no fair clicking through to the Local Language Program Web page and comparing the pictures! Non-use...

Up until Windows XP, applications could intercept the message and tell Windows, "No, don't shut down." If they were polite about it, they would also inform the user which application blocked system shutdown and why. And if they were really polite about it, they would even provide a way for the user to say, "I don't care; shut down anyway." A...