September 2009 | The Old New Thing

2009 Q3 link clearance: Microsoft blogger edition

Raymond Chen September 30, 2009 Sep 30, 2009 09/30/09

It's that time again: Sending some link love to my colleagues...

Why do messages posted by PostThreadMessage disappear?

Raymond Chen September 30, 2009 Sep 30, 2009 09/30/09

The only thread message you can meaningfully post to a thread displaying UI is WM_NULL, and even then, it's only because you want to wake up the message loop for some reason. A common problem I see is people who use PostThreadMessage to talk to a thread that is displaying UI and then wonder why the message never arrives. Oh, the message ...

Microspeak: Net net

Raymond Chen September 29, 2009 Sep 29, 2009 09/29/09

In finance, the net is the total after you have cancelled positive values against negative values. For example, if you took in $30 and paid out $20, then your net is $10. In Microspeak, this term has moved into project planning and has undergone redoubling, so it's not just net; it's net net. The doubling of the word was probably added to ...

Why doesn't Explorer have an interface for creating hard links?

Raymond Chen September 28, 2009 Sep 28, 2009 09/28/09

Nick asks why Explorer doesn't have UI for creating hard links. Heck, while you're at it, why not ask "Why doesn't Explorer have a UI for hex-editing a file?" Remember, all features start out with minus 100 points. Explorer is not under any obligation to expose every last NTFS feature, and it's certainly not going to help to expose an NTFS...

The ways people mess up IUnknown::QueryInterface, episode 2

Raymond Chen September 25, 2009 Sep 25, 2009 09/25/09

Sadly, I get to add another entry to The ways people mess up IUnknown::QueryInterface: Blindly responding to everything. Some people are just too eager to please. No matter what the interface is, they say, "Sure, we do that!" Furthermore, no matter what you ask for, they always return the same interface. Even if it's not what you ...

Don't panic, it's just H1N1

Raymond Chen September 24, 2009 Sep 24, 2009 09/24/09

The media simply can't resist a good panic story, even when there is no panic to be found. On the Media interviews sociology professor Eric Klinenberg on what happens when the media ask you to talk about the nonexistent widespread panic over H1N1. Klinenberg says to the reporter, effectively, "There is no panic." Undaunted by the lack of ...

When people ask for security holes as features: Privileged execution

Raymond Chen September 24, 2009 Sep 24, 2009 09/24/09

A customer wanted to know if there was a way to execute privileged instructions without having to write a driver. "I just need to execute a few instructions, and writing a driver would be overkill since it's only three instructions. Is there a way I can execute these privileged instructions without a driver?" The whole point of having a ...

The COM marshaller uses the COM task allocator to allocate and free memory

Raymond Chen September 23, 2009 Sep 23, 2009 09/23/09

It should be second nature to you that the code which allocates memory and the code which frees memory need to use the same allocator. Most of the time, you think of it as "If you allocate memory, you need to free it with the corresponding mechanism," but this sentence works in the reverse direction as well: If you hand memory to a function ...

We’ve got your hotel surrounded (on one side) (and not even the entire side)

Raymond Chen September 23, 2009 Sep 23, 2009 09/23/09

A local hotel advertises itself like so: Surrounding the hotel are popular Seattle attractions such as Pike Place Market, the Space Needle, Safeco Park, home of baseball's Seattle Mariners, and Qwest Field, home of football's Seattle Seahawks, all just a short drive away. Okay, first, it's Safeco Field, not Safeco Park. Mind you, I've ...

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