VC plus plus

Tips

Latest Articles

Will the trend of reverse offshoring continue?
August 06, 2008
A Windows Device Driver Primer (2/10): Device Driver Programming
July 16, 2008
A Windows Device Driver Primer (1/10): Introduction
July 08, 2008
Demystifying Penetration Tests – Planning and Managing Tests (Part 4 of 4)
June 04, 2008
Demystifying Penetration Tests – Classification of Tests (Part 3 of 4)
May 27, 2008
Demystifying Penetration Tests – Attack Vectors (Part 2 of 4)
May 20, 2008
Chapter 1: Security Principles and the SDL (Online Book Preview)
May 20, 2008
Strategic Outsourcing – The Art and Craft of Outsourcing for Long Term Benefit (1/4)
May 13, 2008
Data Protection and Privacy – The Indian Paradigm
May 07, 2008
Conversations Within Asia – Stage 1: India and Japan
May 07, 2008

“Chishiki” is Japanese for “knowledge.” e-chishiki.com aims to bring software developers, information security professionals, IT executives and other IT pros a rich body of knowledge in the form of articles, interviews, tutorials and technical discussions. Our contributors are among the biggest names in the Indian IT industry and include noted authors, educators and practitioners.

VC++: What are the series of actions that take place when I try to close a window?

Yashavant Kanetkar

December 26, 2007

What are the series of actions that take place when I try to close a window?

When we try to close an application by clicking on the close button, a WM_CLOSE message is sent to our application. If we do not handle this message then it is passed on to the default window procedure. The default window procedure destroys the window by calling the ::DestroyWindow( ) API function. This function places a WM_DESTROY message in the message queue of our application. If we do not handle this message once again the default window procedure gets a shot at it. Following WM_DESTROY, is another message called WM_NCDESTROY. In reaction to this message a handler OnNcDestroy( ) gets called. This handler calls another function・b>PostNcDestroy( ). It is in this function that the ::PostQuitMessage( ) function is called. This function places a message WM_QUIT in the message queue. When this message is retrieved, the message loop is terminated. This ultimately leads to termination of the application.