Added docs for new timezone support added at #6788 (#6865)

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Ivan Kurnosov 2017-09-19 21:23:34 +12:00 committed by Zbigniew Jędrzejewski-Szmek
parent ffa69a04be
commit 54d3be9772

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@ -122,8 +122,12 @@
<title>Parsing Timestamps</title>
<para>When parsing, systemd will accept a similar syntax, but expects no timezone specification, unless it is given
as the literal string <literal>UTC</literal> (for the UTC timezone) or is specified to be the locally configured
timezone. Other timezones than the local and UTC are not supported. The weekday specification is optional, but when
as the literal string <literal>UTC</literal> (for the UTC timezone), or is specified to be the locally configured
timezone, or the timezone name in the IANA timezone database format. The complete list of timezones
supported on your system can be obtained using the <literal>timedatectl list-timezones</literal>
(see <citerefentry><refentrytitle>timedatectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>).
Using IANA format is recommended over local timezone names, as less prone to errors (eg: with local timezone it's possible to
specify daylight saving time in winter, while it's incorrect). The weekday specification is optional, but when
the weekday is specified, it must either be in the abbreviated (<literal>Wed</literal>) or non-abbreviated
(<literal>Wednesday</literal>) English language form (case does not matter), and is not subject to the locale
choice of the user. Either the date, or the time part may be omitted, in which case the current date or 00:00:00,
@ -159,22 +163,23 @@
(assuming the current time was 2012-11-23 18:15:22 and the timezone
was UTC+8, for example TZ=Asia/Shanghai):</para>
<programlisting>Fri 2012-11-23 11:12:13 → Fri 2012-11-23 11:12:13
2012-11-23 11:12:13 → Fri 2012-11-23 11:12:13
2012-11-23 11:12:13 UTC → Fri 2012-11-23 19:12:13
2012-11-23 → Fri 2012-11-23 00:00:00
12-11-23 → Fri 2012-11-23 00:00:00
11:12:13 → Fri 2012-11-23 11:12:13
11:12 → Fri 2012-11-23 11:12:00
now → Fri 2012-11-23 18:15:22
today → Fri 2012-11-23 00:00:00
today UTC → Fri 2012-11-23 16:00:00
yesterday → Fri 2012-11-22 00:00:00
tomorrow → Fri 2012-11-24 00:00:00
+3h30min → Fri 2012-11-23 21:45:22
-5s → Fri 2012-11-23 18:15:17
11min ago → Fri 2012-11-23 18:04:22
@1395716396 → Tue 2014-03-25 03:59:56</programlisting>
<programlisting> Fri 2012-11-23 11:12:13 → Fri 2012-11-23 11:12:13
2012-11-23 11:12:13 → Fri 2012-11-23 11:12:13
2012-11-23 11:12:13 UTC → Fri 2012-11-23 19:12:13
2012-11-23 → Fri 2012-11-23 00:00:00
12-11-23 → Fri 2012-11-23 00:00:00
11:12:13 → Fri 2012-11-23 11:12:13
11:12 → Fri 2012-11-23 11:12:00
now → Fri 2012-11-23 18:15:22
today → Fri 2012-11-23 00:00:00
today UTC → Fri 2012-11-23 16:00:00
yesterday → Fri 2012-11-22 00:00:00
tomorrow → Fri 2012-11-24 00:00:00
tomorrow Pacific/Auckland → Thu 2012-11-23 19:00:00
+3h30min → Fri 2012-11-23 21:45:22
-5s → Fri 2012-11-23 18:15:17
11min ago → Fri 2012-11-23 18:04:22
@1395716396 → Tue 2014-03-25 03:59:56</programlisting>
<para>Note that timestamps displayed by remote systems with a non-matching timezone are usually not parsable
locally, as the timezone component is not understood (unless it happens to be <literal>UTC</literal>).</para>
@ -238,9 +243,9 @@
second component is not specified, <literal>:00</literal> is
assumed.</para>
<para>A timezone specification is not expected, unless it is given as the literal string <literal>UTC</literal>, or
the local timezone, similar to the supported syntax of timestamps (see above). Non-local timezones except for UTC
are not supported.</para>
<para>Timezone can be specified as the literal string <literal>UTC</literal>, or
the local timezone, similar to the supported syntax of timestamps (see above), or the timezone
in the IANA timezone database format (also see above).</para>
<para>The following special expressions may be used as shorthands for longer normalized forms:</para>
@ -286,6 +291,7 @@ Wed..Sat,Tue 12-10-15 1:2:3 → Tue..Sat 2012-10-15 01:02:03
daily UTC → *-*-* 00:00:00 UTC
monthly → *-*-01 00:00:00
weekly → Mon *-*-* 00:00:00
weekly Pacific/Auckland → Mon *-*-* 00:00:00 Pacific/Auckland
yearly → *-01-01 00:00:00
annually → *-01-01 00:00:00
*:2/3 → *-*-* *:02/3:00</programlisting>