DOCUMENT:Q81332  06-DEC-1999  [win16sdk]
TITLE   :HookAll2.exe Demos WH_CALLWNDPROC & WH_GETMESSAGE Hooks
PRODUCT :Microsoft Windows Software Development Kit
PROD/VER:WINDOWS:3.1
OPER/SYS:
KEYWORDS:kbfile kbsample kb16bitonly kbHook kbGrpDSUser kbOSWin310

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The information in this article applies to:

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

HookAll2.exe is a sample that demonstrates how to use the WH_GETMESSAGE and
WH_CALLWNDPROC hooks in Windows 3.1. HookAll2.exe contains the code for a
dynamic-link library (DLL) with functions that set and remove the hooks, as well
as the hook filter functions. The DLL uses the new hook functions provided by
Windows 3.1: SetWindowsHookEx, UnhookWindowsHookEx, and CallNextHookEx.
HookAll2.exe also contains code for a TESTHOOK application that tests the DLL.

HookAll2.exe updates the HOOKALL sample to use the features provided by Windows
3.1. For more information about HOOKALL, query on the following words in the
Microsoft Knowledge Base:

   " hookall " (without the quotation marks)

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

The following files are available for download from the Microsoft Download
Center:

HookAll2.exe

For additional information about how to download Microsoft Support files, click
the article number below to view the article in the Microsoft Knowledge Base:

   Q119591 How to Obtain Microsoft Support Files from Online Services

Microsoft used the most current virus detection software available on the date of
posting to scan this file for viruses. Once posted, the file is housed on secure
servers that prevent any unauthorized changes to the file.


With the exception of WM_LBUTTONDOWN messages, the hook filter functions pass all
messages directly to the next hook function in the hook chain. When they receive
a WM_LBUTTONDOWN message, the filter functions draw a rectangle of random size
and color in the TESTHOOK application's client area. One corner of the rectangle
is at the point where the user pressed the mouse button.

Additional query words:

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Keywords          : kbfile kbsample kb16bitonly kbHook kbGrpDSUser kbOSWin310 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310
Version           : WINDOWS:3.1

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THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 1999.