October 2012 | The Old New Thing

The TEMP directory is like a public hot tub whose water hasn’t been changed in over a year

Raymond Chen October 31, 2012 Oct 31, 2012 10/31/12

All sorts of germs.

The wisdom of seve^H^H^H^Hsixth graders: Living without electronics for a week

Raymond Chen October 30, 2012 Oct 30, 2012 10/30/12

Sixth grade students (ages 11 to 12, roughly) were instructed to imagine that they have no television, computer, or telephone for a week and write an essay (in the form of a letter to their parents) on what they would do with their time and why. The assignment was given under standardized test conditions: 90 minutes with nothing but pencil and...

Keyboard shortcut for resizing all columns in a listview control to fit

Raymond Chen October 30, 2012 Oct 30, 2012 10/30/12

The keyboard shortcut for resizing all columns in a report-mode (also known as Details mode) list view control to fit the current content width is Ctrl+Num+. That's the + key on the numeric keypad. (If you're using Explorer, you can also right-click the column header and choose Size All Columns to Fit.) Note that this command is a verb, not...

In the conversion to 64-bit Windows, why were some parameters not upgraded to SIZE_T?

Raymond Chen October 29, 2012 Oct 29, 2012 10/29/12

James wonders why many functions kept DWORD for parameter lengths instead of upgrading to SIZE_T or DWORD_PTR. When updating the interfaces for 64-bit Windows, there were a few guiding principles. Here are two of them. Don't change an interface unless you really need to. Do you really need to? Changing an interface causes all sorts of ...

Whether the Unicode Bidi algorithm is intuitive depends on your definition of "intuitive"

Raymond Chen October 26, 2012 Oct 26, 2012 10/26/12

In Windows, we spend a good amount of time with the pseudo-mirrored build. And one of the things that you notice is that pseudo-mirrored text comes out looking really weird. For example, the string really? (yup). comes out pseudo-mirrored as .(really? (yup. Just for fun, here's here's how your browser renders it: really? (yup). Even ...

Keyboard layouts aren't like Beetlejuice – they won't appear just because you say their name

Raymond Chen October 25, 2012 Oct 25, 2012 10/25/12

A customer reported a bug in Windows Vista Home Editions: We are handling a Ctrl+V keyboard event and want to interpret it in the context of a US-English keyboard. On Windows XP and versions of Windows Vista other than Home editions, the three calls all succeed, whereas on Windows Vista Home Editions, the calls fail. On the other ...

You can't use the WM_USER message in a dialog box

Raymond Chen October 24, 2012 Oct 24, 2012 10/24/12

Today, I'm not actually going to say anything new. I'm just going to collate information I've already written under a better title to improve search engine optimization. A customer reported that they did the following but found that it didn't work: "I send the MDM_SETITEMCOUNT message to my dialog, but the value doesn't stick. ...

Diversion: Generating a random color from JavaScript

Raymond Chen October 23, 2012 Oct 23, 2012 10/23/12

A colleague posed a little puzzle for a fun little app he was writing in HTML: He wanted to generate a random color. If you search around the intertubes, you can find several possible attempts at a solution, like this collection, and an interesting example that has trouble with the pigeonhole principle. The original function to generate...

How do you come up with new shortcut keys?

Raymond Chen October 22, 2012 Oct 22, 2012 10/22/12

Anon asks, "How do you come up with new shortcut keys and how do you deal with different keyboard layouts? What is the process; is there a company-wide procedure to keep things consistent?" This is several questions (none of them really a suggestion, but I've given up on making the Suggestion Box about suggestions; now it's just the "Ask ...

Using WM_COPYDATA to marshal message parameters since the window manager otherwise doesn’t know how

Raymond Chen October 19, 2012 Oct 19, 2012 10/19/12

Miral asks for the recommended way of passing messages across processes if they require custom marshaling. There is no one recommended way of doing the custom marshaling, although some are hackier than others. Probably the most architecturally beautiful way of doing it is to use a mechanism that does perform automatic marshaling, like COM ...

The Old New Thing