NAME

    DateTime::TimeZone::Local::Win32 - Determine the local system's time
    zone on Windows

VERSION

    version 1.97

SYNOPSIS

      my $tz = DateTime::TimeZone->new( name => 'local' );
    
      my $tz = DateTime::TimeZone::Local->TimeZone();

DESCRIPTION

    This module provides methods for determining the local time zone on a
    Windows platform.

NAME

    DateTime::TimeZone::Local::Win32 - Determine the local system's time
    zone on Windows

HOW THE TIME ZONE IS DETERMINED

    This class tries the following methods of determining the local time
    zone:

      * $ENV{TZ}

      It checks $ENV{TZ} for a valid time zone name.

      * Windows Registry

      When using the registry, we look for the Windows time zone and use a
      mapping to translate this to an IANA time zone name.

	* Windows Vista, 2008 Server and newer Windows operating systems

	We look in "SYSTEM/CurrentControlSet/Control/TimeZoneInformation/"
	for a node named "/TimeZoneKeyName". If this exists, we use this
	key to look up the IANA time zone name in our mapping.

	* Windows NT, Windows 2000, Windows XP, Windows 2003 Server

	We look in "SOFTWARE/Microsoft/Windows NT/CurrentVersion/Time
	Zones/" and loop through all of its sub keys.

	For each sub key, we compare the value of the key with "/Std"
	appended to the end to the value of
	"SYSTEM/CurrentControlSet/Control/TimeZoneInformation/StandardName"
	. This gives us the English name of the Windows time zone, which we
	use to look up the IANA time zone name.

	* Windows 95, Windows 98, Windows Millenium Edition

	The algorithm is the same as for NT, but we loop through the sub
	keys of "SOFTWARE/Microsoft/Windows/CurrentVersion/Time Zones/"

AUTHORS

      * David Pinkowitz <dapink@cpan.org>

      * Dave Rolsky <autarch@urth.org>

COPYRIGHT AND LICENSE

    Copyright (C) 2007-2014 Dave Rolsky <autarch@urth.org> Copyright (C)
    2014-2017 by David Pinkowitz <dapink@cpan.org>

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.