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Q86266: DOC: Overview Manual Documents PostAppMessage Incorrectly

Article: Q86266
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.1
Operating System(s): 
Keyword(s): kbdocfix kb16bitonly kbSDKPlatform kbWndw kbWndwMsg
Last Modified: 11-JUN-1999

3.10
WINDOWS
kbprg kbdocerr

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) 3.1 
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SUMMARY
=======

Section 1.1.4 (page 10) of the "Microsoft Windows Software Development Kit:
Programmer's Reference, Volume 1: Overview" manual for version 3.1 documents
that the PostAppMessage function posts a message to an application using its
module handle. This statement is incorrect; PostAppMessage posts a message to an
application using its task handle.

MORE INFORMATION
================

Microsoft Windows makes a very important distinction between a task handle and a
module handle. Each instance of an application has exactly one task, which
consists of a stack, a message queue, and an execution state (CPU registers).
However, all instances of an application share the same module, which consists
of the application's executable code and resources.

One cannot post a message to a module for two reasons:

- A module does not have a message queue; therefore, it cannot process a
  message.

- Potentially, several application instances (tasks) share a module; therefore,
  a module handle does not identify a unique task to receive the message.

By posting a message to a task handle, the message is sent to only one instance
of an application.

Additional query words: 3.10 SDK docerr

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Keywords          : kbdocfix kb16bitonly kbSDKPlatform kbWndw kbWndwMsg 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310
Version           : WINDOWS:3.1

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