October 2018 | The Old New Thing

Dulce et decorum est pro patria party

Raymond Chen October 31, 2018 Oct 31, 2018 10/31/18

On April 2, 1996, at the then-named Computer Game Developers Conference, Microsoft introduced DirectX 2.0 to great fanfare. And by great fanfare, I mean "ridiculous fanfare." Read Jay Barnson's account of the event. Do it. I did not attend the party, but I did receive a surplus toga kit. I've donated it to the Microsoft archives. The ...

What happened to the Arial Unicode MS font?

Raymond Chen October 30, 2018 Oct 30, 2018 10/30/18

A customer wanted to know what happened to the Arial Unicode MS font. It used to be installed with Microsoft Office, but was dropped starting with Microsoft Office 2016. Various conspiracy theories have developed as to why. Wikipedia cites a Microsoft forum answer that says that When Microsoft included Arial Unicode MS with earlier versions ...

The case of the oplock deadlock poppycock

Raymond Chen October 29, 2018 Oct 29, 2018 10/29/18

A customer reported that their application would sometimes hang trying to open a file. The call to CreateFile would simply hang, rather than failing with ERROR_SHARING_VIOLATION or some other error code. One case where a CreateFile can hang is when there is an oplock on the file that needs to be broken. Explorer takes an oplock on ...

How do I prevent users from using the mouse to drag the trackbar thumb to positions that aren’t multiples of five? Part 2: Nudging the thumb position

Raymond Chen October 26, 2018 Oct 26, 2018 10/26/18

Last time, we investigated one approach to the problem of keeping a trackbar position on multiples of five: Just divide everything by five! (And then multiply by five when you read the value.) This works great, except that accessibility tools report the range as 0–20 in one-unit increments, even though you are presenting it to the user ...

How do I prevent users from using the mouse to drag the trackbar thumb to positions that aren’t multiples of five? Part 1: Reframe the problem

Raymond Chen October 25, 2018 Oct 25, 2018 10/25/18

A customer had a trackbar common control, set the range to 0–100, set the line size to 5 (so that pressing an arrow key moves the thumb by five units), and set the page size to 20 (so that pressing the PgUp and PgDn keys move the thumb by twenty units). This ensures that the keyboard can set the trackbar position only to values that are ...

Adding a Ctrl+arrow accelerator for moving the trackbar by just one unit, part 2: Second try

Raymond Chen October 24, 2018 Oct 24, 2018 10/24/18

Last time, we looked at how we could add support to the trackbar so that Ctrl+arrow moved the thumb by one unit, even if the line size was set to a larger value. We tried doing this by subclassing the control and adding additional keyboard handling, but this turned into a bit of a mess because of all the special cases in the trackbar to ...

Adding a Ctrl+arrow accelerator for moving the trackbar by just one unit, part 1: Initial plunge

Raymond Chen October 23, 2018 Oct 23, 2018 10/23/18

When you create a trackbar common control, you can specify how far the arrow keys will change the trackbar position (default: 1 unit) and how far the PgUp and PgDn keys will change the trackbar position (default: one fifth of the range). If you change the default distance for the arrow keys to, say, five units, then you probably want to add a...

Why does the Entry Point Not Found error dialog sometimes not include the name of the missing entry point?

Raymond Chen October 22, 2018 Oct 22, 2018 10/22/18

A customer observed that sometimes the Entry Point Not Found error dialog does not include the name of the missing entry point. Usually, it looks like this: Contoso.exe - Entry Point Not Found But sometimes it looks like this: Contoso.exe - Entry Point Not Found Why does the error message sometimes leave out the name of the ...

File-extending writes are not always synchronous, which is entirely within the contract

Raymond Chen October 19, 2018 Oct 19, 2018 10/19/18

I noted some time ago that the current implementation of NTFS forces certain kinds of writes to be synchronous, even when issued asynchronously. Note that this is an implementation decision which is not contractual. Formally, the rule is that any asynchronous operation is permitted (but not required) to complete synchronously. Malcolm Smith ...

After reporting a non-responsive program to Windows Error Reporting, why does the process spawn a suspended child process?

Raymond Chen October 18, 2018 Oct 18, 2018 10/18/18

That's just a ghost, a shadow of the original.

The Old New Thing