DOCUMENT:Q123809  29-JUL-2001  [visualc]
TITLE   :FIX: Development Environment Doesn't Unload DLL on Termination
PRODUCT :Microsoft C Compiler
PROD/VER:2.00
OPER/SYS:
KEYWORDS:kbide kbVC600fix kbGrpDSToolskbbuglist

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The information in this article applies to:

 - Microsoft Visual C++, 32-bit Editions, version 2.0 
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SYMPTOMS
========

The Visual C++ development environment may fail to unload a DLL from memory if
an abnormal program termination occurs.

CAUSE
=====

The Visual C++ development environment loads the DLLs into memory when the
application starts in the debugger. An abnormal program termination may cause
the debugger to fail to remove the DLLs from memory.

RESOLUTION
==========

When this happens, you need to exit the development environment and possibly
even log off Windows NT to force the DLL to be removed from memory.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This problem was corrected in Microsoft Visual C++,
version 6.0.


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

To reproduce this problem, it is necessary to create a Win32-based application
that calls a Win32-based DLL. That DLL should call another DLL. You can use the
SELECT example from the Win32 SDK samples, and add another DLL with a single
function. Call it from one of the SELECT.DLL functions.

Once this is set up, remove the secondary DLL from your hard drive. Then attempt
to debug the program in the Visual C++ development environment. An error message
will appear saying it could not find the secondary DLL, and the executable will
terminate.

Now, attempt to delete the primary DLL being called. Windows will generate an
error message saying that the primary DLL is still in use, even though the
application calling the DLL was terminated.

Additional query words: IDE

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Keywords          : kbide kbVC600fix kbGrpDSTools kbbuglist
Technology        : kbVCsearch kbAudDeveloper kbVC200 kbVC32bitSearch
Version           : 2.00
Issue type        : kbbug
Solution Type     : kbfix

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