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Q45704: Using GlobalFlags() to Test for GMEM_DISCARDABLE

Article: Q45704
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 06-NOV-1999

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1 
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SUMMARY
=======

When testing for GMEM_DISCARDABLE, do not use the following:

     if(GlobalFlags(hMem) == GMEM_DISCARDABLE)

Instead, use the following:

     if(GlobalFlags(hMem) & GMEM_DISCARDABLE)

This is necessary because GlobalFlags() returns a one, i.e., 0x0100, rather than
0x0F00 if the object is discardable. It is also possible that the return value
could be 0x0800 or 0x0400 or 0x0200. These cases are also taken care of with the
bitwise AND.

Additional query words: 3.00 3.10

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1

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