The Old New Thing

How do I perform shell file operations while avoiding shell copy hooks?

March 30, 2012 Mar 30, 2012 03/30/12

Raymond Chen

Okay, the subject line of the article gives away the answer to the puzzle, but here's the puzzle anyway: A customer reported a problem with the function: Consider the following program: If "a" is a file, then everything works fine, but if it's a directory, then Application Verifier raises the following error: Heap violation detected ...

Why can't I delete a file immediately after terminating the process that has the file open?

March 29, 2012 Mar 29, 2012 03/29/12

Raymond Chen

A customer discovered a bug where terminating a process did not close the handles that the process had open, resulting in their emergency cleanup code not working: Their workaround was to insert a call to before deleting the file. The customer wanted to know whether they discovered a bug in , and they were concerned that their workaround ...

Why does a maximized window have the wrong window rectangle?

March 26, 2012 Mar 26, 2012 03/26/12

Raymond Chen

Commenter configurator wonders why the maximum size for a form is the screen size plus (12,12). Somebody else wonders why it's the screen size plus (16,16). Let's start by rewinding the clock to Windows 3.0. When you maximize a window, the default position of the window is such that all the resizing borders hang "off the edges of the ...

Why is the Heap32Next function incredibly slow on Windows 7?

March 23, 2012 Mar 23, 2012 03/23/12

Raymond Chen

Improved correctness but at a price.

Why does my window style change when I call SetWindowText?

March 22, 2012 Mar 22, 2012 03/22/12

Raymond Chen

A customer observed some strange behavior with window styles: We ran some weird behavior: Calling the function causes a change in window styles. Specifically, calling results in the and messages, and sometimes the result is that the style is removed. Is this a bug? What would cause this? The message sends the message to the control, ...

Isn't there a race condition in GetFileVersionInfoSize?

March 21, 2012 Mar 21, 2012 03/21/12

Raymond Chen

In response to my explanation of what the parameter in is used for, Steve Nuchia wonders if there's a race condition between the time you get the size and the time you ask for the data. Yes, there is a race condition, but calling the function in a loop won't help because the function does not report that the buffer is too small to hold ...