Newsgroups: comp.std.c
Path: utzoo!utgpu!watserv1!watmath!datangua
From: datangua@watmath.waterloo.edu (David Tanguay)
Subject: Re: Questions about mktime()
Organization: University of Waterloo
Date: Mon, 21 Jan 91 11:52:49 GMT
Message-ID: <1991Jan21.115249.24661@watmath.waterloo.edu>
References: <1991Jan18.225155.7310@druid.uucp> <1991Jan20.205039.7056@sq.sq.com>
Lines: 18

In article <1991Jan20.205039.7056@sq.sq.com> msb@sq.sq.com (Mark Brader) writes:
|The rule is that if tm_isdst is positive, you have to assume Daylight
|Saving Time; if zero, you have to assume Standard Time; if negative, you
|have to "attempt to determine whether Daylight Saving Time is in effect
|for the specific time".
[...]
|One way to do this would be to first assume Standard Time, adjusting
|the computed time by 3600 seconds if tm_isdst was positive; then call
                      ^^^^
|localtime() on the computed time, and see what it gives for tm_isdst;
|if it's 1, adjust the computed time by 3600 seconds and call localtime()
|again.  If tm_isdst was originally positive or zero, you're done.

Now what do we do with the double DST that Newfoundland has/had?
Not only do you have to figure out if DST is in effect, you have to figure
out exactly how much of a time shift DST represents.
-- 
David Tanguay            Software Development Group, University of Waterloo