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From: altman@sbpmt.cs.sunysb.edu (Jeff Altman)
Newsgroups: comp.windows.ms.programmer
Subject: Re: tzset and Windows
Message-ID: <1991Mar27.203753.20851@sbcs.sunysb.edu>
Date: 27 Mar 91 20:37:53 GMT
References: <1991Mar27.020414.2525@sbcs.sunysb.edu>
Sender: usenet@sbcs.sunysb.edu (Usenet poster)
Organization: State University of New York at Stony Brook
Lines: 21

Well, it wasn't a windows problem.  Its a problem with
unclear documentation in Borland C++ (and probably every
other C Library reference manual.)

The problem is that gmtime and localtime both return 
pointers to structures that the manual refers to as
static structures that are re-written with each call.
What the manual does NOT say is that gmtime and localtime
both use the SAME static structure.

So:
	gmt = gmtime(&t) ;
	lt  = localtime(&t) ;
	printf (asctime(lt)) ;
	printf (asctime(gmt)) ;

both use the localtime value.


--
- Jeff (jaltman@ccmail.sunysb.edu)