forked from KolibriOS/kolibrios
86 lines
4.3 KiB
Plaintext
86 lines
4.3 KiB
Plaintext
Timezone strings:
|
|
-----------------
|
|
This is a description of valid timezone strings for ENV[ARC]:TZ:
|
|
"XPG3TZ - time zone information"
|
|
The form of the time zone information is based on the XPG3 specification of
|
|
the TZ environment variable. Spaces are allowed only in timezone
|
|
designations, where they are significant. The following description
|
|
closely follows the XPG3 specification, except for the paragraphs starting
|
|
**CLARIFICATION**.
|
|
|
|
<std><offset>[<dst>[<offset>],<start>[/<time>],<end>[/<time>]]
|
|
|
|
Where:
|
|
<std> and <dst>
|
|
Are each three or more bytes that are the designation for the
|
|
standard (<std>) and daylight savings time (<dst>) timezones.
|
|
Only <std> is required - if <dst> is missing, then daylight
|
|
savings time does not apply in this locale. Upper- and
|
|
lower-case letters are allowed. Any characters except a
|
|
leading colon (:), digits, a comma (,), a minus (-) or a plus
|
|
(+) are allowed.
|
|
**CLARIFICATION** The two-byte designation `UT' is permitted.
|
|
<offset>
|
|
Indicates the value one must add to the local time to arrive
|
|
at Coordinated Universal Time. The offset has the form:
|
|
<hh>[:<mm>[:<ss>]]
|
|
The minutes <mm> and seconds <ss> are optional. The hour <hh>
|
|
is required and may be a single digit. The offset following
|
|
<std> is required. If no offset follows <dst>, daylight savings
|
|
time is assumed to be one hour ahead of standard time. One or
|
|
more digits may be used; the value is always interpreted as a
|
|
decimal number. The hour must be between 0 and 24, and the
|
|
minutes (and seconds) if present between 0 and 59. Out of
|
|
range values may cause unpredictable behavior. If preceded by
|
|
a `-', the timezone is east of the Prime Meridian; otherwise
|
|
it is west (which may be indicated by an optional preceding
|
|
`+' sign).
|
|
**CLARIFICATION** No more than two digits are allowed in any
|
|
of <hh>, <mm> or <ss>. Leading zeros are permitted.
|
|
<start>/<time> and <end>/<time>
|
|
Indicates when to change to and back from daylight savings
|
|
time, where <start>/<time> describes when the change from
|
|
standard time to daylight savings time occurs, and
|
|
<end>/<time> describes when the change back happens. Each
|
|
<time> field describes when, in current local time, the change
|
|
is made.
|
|
**CLARIFICATION** It is recognized that in the Southern
|
|
hemisphere <start> will specify a date later than <end>.
|
|
The formats of <start> and <end> are one of the following:
|
|
J<n> The Julian day <n> (1 <= <n> <= 365). Leap days are not
|
|
counted. That is, in all years, February 28 is day 59
|
|
and March 1 is day 60. It is impossible to refer to
|
|
the occasional February 29.
|
|
<n> The zero-based Julian day (0 <= <n> <= 365). Leap days
|
|
are counted, and it is possible to refer to February
|
|
29.
|
|
M<m>.<n>.<d>
|
|
The <d>th day, (0 <= <d> <= 6) of week <n> of month <m>
|
|
of the year (1 <= <n> <= 5, 1 <= <m> <= 12), where week
|
|
5 means `the last <d>-day in month <m>' (which may
|
|
occur in either the fourth or the fifth week). Week 1
|
|
is the first week in which the <d>th day occurs. Day
|
|
zero is Sunday.
|
|
**CLARIFICATION** Neither <n> nor <m> may have a
|
|
leading zero. <d> must be a single digit.
|
|
**CLARIFICATION** The default <start> and <end> values
|
|
are from the first Sunday in April until the last Sunday
|
|
in October. This allows United States users to leave out
|
|
the <start> and <end> parts, as most are accustomed to
|
|
doing.
|
|
<time> has the same format as <offset> except that no leading
|
|
sign (`-' or `+') is allowed. The default, if <time> is not
|
|
given is 02:00:00.
|
|
**CLARIFICATION** The number of hours in <time> may be up
|
|
to 167, to allow encoding of rules such as `00:00hrs on the
|
|
Sunday after the second Friday in September'
|
|
|
|
Example (for Central Europe):
|
|
-----------------------------
|
|
MET-1MEST,M3.5.0,M10.5.0/03
|
|
|
|
Another example, for the US East Coast:
|
|
---------------------------------------
|
|
EST5EDT4,M4.1.0/02,M10.5.0/02
|
|
This string describes the default values when no time zone is set.
|