Q92500: PRB: exit() Function Does Not Clean Up Nonstatic Objects

Article: Q92500
Product(s): Microsoft C Compiler
Version(s): 1.0,1.5,1.51,1.52,2.0,2.1,4.0,4.1,4.2,5.0,6.0
Operating System(s): 
Keyword(s): kbLangCPP kbVC100 kbVC150 kbVC151 kbVC152 kbVC200 kbVC210 kbVC400 kbVC410 kbVC420 kbVC5
Last Modified: 29-NOV-2001

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The information in this article applies to:

- Microsoft C/C++ for MS-DOS 
- Microsoft Visual C++, versions 1.0, 1.5, 1.51, 1.52, 2.0, 2.1, 4.0, 4.1 
- Microsoft Visual C++, 32-bit Enterprise Edition, versions 4.2, 5.0, 6.0 
- Microsoft Visual C++, 32-bit Professional Edition, versions 4.2, 5.0, 6.0 
- Microsoft Visual C++, 32-bit Learning Edition, version 6.0 
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SYMPTOMS
========

When an application calls the exit(), _exit(), _cexit(), or _c_exit() functions,
the destructors for any temporary or automatic objects that exist at the time of
the call are not called. The text below provides a sample program to demonstrate
this behavior.

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

An automatic object is an object that is defined in a function where the object
is not declared to be "static." A temporary object is an object created by the
compiler.

To destruct an automatic object before calling exit(), explicitly call the
destructor for the object, as follows:

  myObject.myClass::~myClass();

Sample Code
-----------

  /* Compile options needed:  for 16-bit - /f /Od /Zi
  *                           for 32-bit - none
  */ 

  #include <iostream.h>
  #include <process.h>

  class myClass
  {
     int nVal;

  public:
     myClass();
     void View() {cout << nVal << "\n";};
     ~myClass();
  };

  myClass::myClass()
  {
     nVal = 99;
  }

  myClass::~myClass()
  {
     cout << "Destructor has been called\n";
  }

  void main(void)
  {
     myClass myObject;

     myObject.View();

  // Remove the comment from the next line to call the destructor
  // myObject.myClass::~myClass();

     exit(0);
  }

Additional query words: 8.00 8.00c 9.00 9.10

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Keywords          : kbLangCPP kbVC100 kbVC150 kbVC151 kbVC152 kbVC200 kbVC210 kbVC400 kbVC410 kbVC420 kbVC500 kbVC600 
Technology        : kbVCsearch kbVC400 kbAudDeveloper kbZNotKeyword8 kbvc150 kbvc100 kbZNotKeyword3 kbVC410 kbVC420 kbVC500 kbVC600 kbVC151 kbVC200 kbVC210 kbVC32bitSearch kbVC152 kbVC500Search
Version           : :1.0,1.5,1.51,1.52,2.0,2.1,4.0,4.1,4.2,5.0,6.0
Issue type        : kbprb

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