DOCUMENT:Q130769  25-JUL-2001  [visualc]
TITLE   :FIX: Negative Value Passed to mktime() Generates Wrong Date
PRODUCT :Microsoft C Compiler
PROD/VER::2.0,2.1
OPER/SYS:
KEYWORDS:kbList kbCompiler

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft C/C++ Compiler (CL.EXE), included with:
    - *EDITOR Please do not choose this product*Microsoft Visual C++ 32-bit Edition* use 241, 265, 225, versions 2.0, 2.1 
-------------------------------------------------------------------------------

SYMPTOMS
========

The wrong date is returned when a negative value is passed for the month to the
mktime() function.

For example, in the sample code in this article, -1 is passed for the month, so
the mktime() function should return December 15, 1994. However, it incorrectly
returns January 16, 1995.

RESOLUTION
==========

Verify that the value for the month is greater than or equal to zero, when
calling the mktime() function.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in Microsoft Visual C++,
32-bit Edition, version 4.0.

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

Sample Code to Reproduce Problem
--------------------------------

      /* Compile options needed: none
      */ 

      #include <time.h>
      #include <stdio.h>

      void main() {
          time_t   CurrentTime, NewTime;
          struct tm TimeStruct;

          time ( &CurrentTime );
          TimeStruct = *localtime(&CurrentTime);
          TimeStruct.tm_mday = 15;
          TimeStruct.tm_mon  = -1;
          TimeStruct.tm_year = 95;

          NewTime = mktime (&TimeStruct);
          printf("%s", asctime( &TimeStruct));
      }

Additional query words: 9.00 9.10

======================================================================
Keywords          : kbList kbCompiler 
Technology        : kbVCsearch kbAudDeveloper kbCVCComp
Version           : :2.0,2.1
Issue type        : kbbug
Solution Type     : kbfix

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

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 2001.