---
name: "DateTime::TimeZone::Local::Win32"
section: "3pm"
platform: "linux"
package: "libdatetime-timezone-perl"
version: "1:1.20-1+2010k"
release: "Debian 6.0 (Squeeze)"
platforms: ["linux"]
url: "https://new.carta.tech/DateTime::TimeZone::Local::Win32"
---

# DateTime::TimeZone::Local::Win32(3pm)

Determine the local system's time zone on Windows

## NAME

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

## 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.

## 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 Olson time zone name.

  - •

    Windows Vista and 2008

    We look in "SYSTEM/CurrentControlSet/Control/TimeZoneInformation/" for a node named "/TimeZoneKeyName". If this exists, we use this key to look up the Olson 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 Olson 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/"

## AUTHOR

Dave Rolsky, \<autarch@urth.org\>

## COPYRIGHT & LICENSE

Copyright (c) 2003-2008 David Rolsky.  All rights reserved.  This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The full text of the license can be found in the LICENSE file included with this module.