August 2014 | Page 2 of 3 | The Old New Thing

News flash: Big houses cost more to maintain

Raymond ChenAugust 18, 2014Aug 18, 201408/18/14

In 2005, we learned that big houses cost more to heat. In 2006, we learned that big houses cost more to cool. But then the research into big houses seems to have stalled. No worries. The research journal The Wall Street Journal recently released a paper concluding that big houses cost more to maintain.

Deleting elements from an JavaScript array and closing up the gaps

Raymond ChenAugust 18, 2014Aug 18, 201408/18/14

Today's Little Program is an exercise that solves the following problem: Given a JavaScript array a and an unsorted array indices (possibly containing duplicates), calculate the result of deleting all of the elements from the original array as specified by the indices. For example, suppose a = ["alice", "bob", "charles", "david", "eve"] an

The scope of the C# checked/unchecked keyword is static, not dynamic

Raymond ChenAugust 15, 2014Aug 15, 201408/15/14

C# has operators checked and unchecked to control the behavior of the language in the face of integer overflow. There are also checked and unchecked statements which apply the behavior to blocks of statements rather than single expressions. Why, then, doesn't this code below raise an overflow exception? (Mini-exercise: Why couldn't I ha

Customers not getting the widgets they paid for if they click too fast -or- In C#, the += operator is not merely not guaranteed to be atomic, it is guaranteed not to be atomic

Raymond ChenAugust 14, 2014Aug 14, 201408/14/14

In the C# language, operation/assignment such as += are explicitly not atomic. But you already knew this, at least for properties. Recall that properties are syntactic sugar for method calls. A property declaration is internally converted to the equivalent of Accessing a property is similarly transformed. Note that the only operation

Keep your eye on the code page: C# edition (the mysterious third code page)

Raymond ChenAugust 13, 2014Aug 13, 201408/13/14

A customer was having trouble manipulating the console from a C# program: We found that C# can read only ASCII data from the console. If we try to read non-ASCII data, we get garbage. Observe that this program is unable to read the Å and ö characters. They come back as garbage. Although there are three code pages that have

Keep your eye on the code page: C# edition (warning about DllImport)

Raymond ChenAugust 12, 2014Aug 12, 201408/12/14

Often, we receive problem reports from customers who failed to keep their eye on the code page. Does the SHGetFileInfo function support files with non-ASCII characters in their names? We find that the function either fails outright or returns question marks when asked to provide information for files with non-ASCII character

Revival of the Daleks: Act One, Scene One

Raymond ChenAugust 11, 2014Aug 11, 201408/11/14

In 2009, a group of volunteers on a routine cleanup of a pond in Hampshire, England discovered a Dalek. (Later in the episode, the story may introduce a scientist who is thawing out a 30,000-year-old-virus.)

If you want to set a thread's apartment model via Thread.CurrentThread.ApartmentState, you need to act quickly

Raymond ChenAugust 11, 2014Aug 11, 201408/11/14

Welcome to CLR Week 2014. Don't worry, it'll be over in a few days. A customer wanted to know why their FolderBrowserDialog was displaying the infamous Current thread must be set to single thread apartment (STA) mode before OLE calls can be made error. "Even though we set the ApartmentState to STA, the apartment state is s

The case of the orphaned LpdrLoaderLock critical section

Raymond ChenAugust 8, 2014Aug 8, 201408/8/14

A customer found that under heavy load, their application would occasionally hang. Debugging the hang shows that everybody was waiting for the LpdrLoaderLock critical section. The catch was that the critical section was reported as locked, but the owner thread did not exist. How can a critical section be owned by thread that no l

The latest technologies in plaintext editing: NotepadConf

Raymond ChenAugust 7, 2014Aug 7, 201408/7/14

On November 13, 2014 November 14, 2014, Saint Paul, Minnesota will be the home to NotepadConf, which bills itself as "the premier technology conference for Notepad.exe users and text enthusiasts." I'm still not sure whom Microsoft will send to the conference, but maybe that person could give a talk on how you can use Notepad to take down th

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