From reading the Perl docs, I've come to the same conclusion: Perl uses the O/S's to determine whether daylight savings time is in effect. Given the need to patch the underlying O/S, application programmers (in Perl, and everything else) may need to manage the DST switch explicitly for quite a while.

Another good reason to do everything in UTC.

Addendum

Poking through the Risks repository, specifically here, I've found out some potentially useful information: All versions of *ix, Windows NT and its derivatives (Windows 2000, XP, etc), and at least the more recent versions of the Mac O/S convert from GMT/UTC (these are almost, but not quite the same thing, by the way) to local time. The older Windows O/S kept local times.

emc

At that time [1909] the chief engineer was almost always the chief test pilot as well. That had the fortunate result of eliminating poor engineering early in aviation.

—Igor Sikorsky, reported in AOPA Pilot magazine February 2003.

In reply to Re: Impact of U.S. Daylight Savings Time changes in 2007 on Perl distribution/code by swampyankee
in thread Impact of U.S. Daylight Savings Time changes in 2007 on Perl distribution/code by kool_delhite

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