diff options
Diffstat (limited to 'dateutil/tz/win.py')
| -rw-r--r-- | dateutil/tz/win.py | 45 |
1 files changed, 42 insertions, 3 deletions
diff --git a/dateutil/tz/win.py b/dateutil/tz/win.py index def4353..cde07ba 100644 --- a/dateutil/tz/win.py +++ b/dateutil/tz/win.py @@ -1,3 +1,11 @@ +# -*- coding: utf-8 -*- +""" +This module provides an interface to the native time zone data on Windows, +including :py:class:`datetime.tzinfo` implementations. + +Attempting to import this module on a non-Windows platform will raise an +:py:obj:`ImportError`. +""" # This code was originally contributed by Jeffrey Harris. import datetime import struct @@ -39,7 +47,7 @@ TZKEYNAME = _settzkeyname() class tzres(object): """ - Class for accessing `tzres.dll`, which contains timezone name related + Class for accessing ``tzres.dll``, which contains timezone name related resources. .. versionadded:: 2.5.0 @@ -72,9 +80,10 @@ class tzres(object): :param offset: A positive integer value referring to a string from the tzres dll. - ..note: + .. note:: + Offsets found in the registry are generally of the form - `@tzres.dll,-114`. The offset in this case if 114, not -114. + ``@tzres.dll,-114``. The offset in this case is 114, not -114. """ resource = self.p_wchar() @@ -146,6 +155,9 @@ class tzwinbase(tzrangebase): return result def display(self): + """ + Return the display name of the time zone. + """ return self._display def transitions(self, year): @@ -188,6 +200,17 @@ class tzwinbase(tzrangebase): class tzwin(tzwinbase): + """ + Time zone object created from the zone info in the Windows registry + + These are similar to :py:class:`dateutil.tz.tzrange` objects in that + the time zone data is provided in the format of a single offset rule + for either 0 or 2 time zone transitions per year. + + :param: name + The name of a Windows time zone key, e.g. "Eastern Standard Time". + The full list of keys can be retrieved with :func:`tzwin.list`. + """ def __init__(self, name): self._name = name @@ -234,6 +257,22 @@ class tzwin(tzwinbase): class tzwinlocal(tzwinbase): + """ + Class representing the local time zone information in the Windows registry + + While :class:`dateutil.tz.tzlocal` makes system calls (via the :mod:`time` + module) to retrieve time zone information, ``tzwinlocal`` retrieves the + rules directly from the Windows registry and creates an object like + :class:`dateutil.tz.tzwin`. + + Because Windows does not have an equivalent of :func:`time.tzset`, on + Windows, :class:`dateutil.tz.tzlocal` instances will always reflect the + time zone settings *at the time that the process was started*, meaning + changes to the machine's time zone settings during the run of a program + on Windows will **not** be reflected by :class:`dateutil.tz.tzlocal`. + Because ``tzwinlocal`` reads the registry directly, it is unaffected by + this issue. + """ def __init__(self): with winreg.ConnectRegistry(None, winreg.HKEY_LOCAL_MACHINE) as handle: with winreg.OpenKey(handle, TZLOCALKEYNAME) as tzlocalkey: |