TZ and tzset Only Use Whole Hours: How to Work Around

 Last reviewed: January 19, 1996
Article ID: Q68383
The information in this article applies to:
  • Microsoft C for MS-DOS, versions 5.1, 6.0, 6.0a, and 6.0ax
  • Microsoft C for OS/2, versions 5.1, 6.0, and 6.0a
  • Microsoft Visual C++ for Windows, versions 1.0 and 1.5
  • Microsoft Visual C++, 32-bit Edition, versions 1.0, 2.0, and 2.1

In Microsoft C versions 5.1, 6.0, 6.0a, and 6.0ax, the TZ environment variable and the tzset() function can use only whole hours for time zone adjustments. These functions cannot be used, for example, to calculate the time in Sri Lanka, which is 330 minutes off of GMT.

The only workaround in C 6.x is to use a second environment variable (for example, TZ2) to add thirty minutes to the times passed by functions that return and use local times.

Beginning with C/C++ version 7.0, tzset() and TZ have been enhanced to accept TZ values of the form tzn[+|-]hh[:mm[:ss]][dzn].

Additional reference words: kbinf 6.00 6.00a 6.00ax 1.00 1.50 2.00 2.10
KBCategory: kbprg kbfasttip
KBSubcategory: CRTIss

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Last reviewed: January 19, 1996
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