I am also curious as to what happens with these ambiguous local times, like in the US 1:23 AM can occur twice during the same day.

What...? Anyway, see the %p and %P tokens.

Invalid offset: CST

As per DateTime::Format::Strptime: "By default, the parser will die when it parses an ambiguous abbreviation."

$ perl -wMstrict -MDateTime -le 'print DateTime->now(time_zone=>$_)->s
+trftime("%Z %z") for qw# America/Havana Asia/Shanghai America/Chicago
+ #'
CST -0500
CST +0800
CST -0600

[download]

See also List of time zone abbreviations, ISO8601 Time zone designators, and Names of time zones.

Also occasionally a specific location can change its time zone - the International Date Line was moved some years back - this affected some islands in the Pacific.

Hence the existence of location-based time zone names that are unambiguous in that respect.

$ perl -wMstrict -MDateTime -le 'print DateTime->new(year=>$_,time_zon
+e=>"Pacific/Apia")->strftime("%Y %z") for qw/ 2010 2012 /'
2010 -1100
2012 +1400

[download]

In reply to Re^4: Question regarding Time::Piece and timezones by haukex
in thread Question regarding Time::Piece and timezones by atcroft

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