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Q142420: DOC: Setdflag.c Sample for _CrtSetDbgFlag Missing Tilde (~)

Article: Q142420
Product(s): Microsoft C Compiler
Version(s): WinNT:4.0,4.1,4.2,5.0
Operating System(s): 
Keyword(s): kbdocerr kbCRT kbVC400 kbVC410 kbVC420 kbVC500
Last Modified: 30-JUL-2001

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The information in this article applies to:

- The C Run-Time (CRT), included with:
   - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Professional Edition, version 4.2 
   - Microsoft Visual C++, 32-bit Enterprise Edition, version 5.0 
   - Microsoft Visual C++, 32-bit Professional Edition, version 5.0 
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SUMMARY
=======

The Setdflag.c sample program in the Help under _CrtSetDbgFlag(), contains the
following section of code which is missing a tilde (~) character:

  /*
  * Set the debug-heap flag to no longer keep freed blocks in the
  * heap's linked list and turn on Debug type allocations (CLIENT)
  */ 
   tmpDbgFlag = _CrtSetDbgFlag(_CRTDBG_REPORT_FLAG);
   tmpDbgFlag |= _CRTDBG_ALLOC_MEM_DF;
   tmpDbgFlag &= _CRTDBG_DELAY_FREE_MEM_DF;  // This line is wrong
   _CrtSetDbgFlag(tmpDbgFlag);

The third line of code should be:

   tmpDbgFlag &= ~_CRTDBG_DELAY_FREE_MEM_DF;

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

To disable a flag with the _CrtSetDbgFlag() function, you should AND the
variable with the bitwise NOT of the bitmask.

Additional query words: kbVC400bug

======================================================================
Keywords          : kbdocerr kbCRT kbVC400 kbVC410 kbVC420 kbVC500 
Technology        : kbVCsearch kbAudDeveloper kbCRT
Version           : WinNT:4.0,4.1,4.2,5.0

=============================================================================

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