usefor-article-03 February 2000
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5.1. Date
The Date header contains the date and time that the article was
prepared by the poster ready for transmission and SHOULD express the
poster's local time. The content syntax makes use of syntax defined
in [MESSFOR].
Date-content = date-time
NOTE: It is a useful convention to follow the date-time with a
comment containing the time zone in human-readable form. The use
of folding in a date-time is deprecated, even though permitted
by [MESSFOR].
In order to prevent the reinjection of expired articles into the news
stream, relaying and serving agents MUST refuse articles whose Date
header predates the earliest articles of which they normally keep
record, or which is more than 24 hours into the future (though they
MAY use a margin less than that 24 hours). Relaying agents MUST NOT
modify the Date header in transit.
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#Diff to first older
--- ../s-o-1036/Date.out June 1994
+++ ../usefor-article-03/Date.out February 2000
@@ -1,107 +1,21 @@
5.1. Date
-The Date header contains the date and time when the article
-was submitted for transmission:
-
- Date-content = [ weekday "," space ] date space time
- weekday = "Mon" / "Tue" / "Wed" / "Thu"
- / "Fri" / "Sat" / "Sun"
- date = day space month space year
- day = 1*2digit
- month = "Jan" / "Feb" / "Mar" / "Apr" / "May" / "Jun"
- / "Jul" / "Aug" / "Sep" / "Oct" / "Nov" / "Dec"
- year = 4digit / 2digit
- time = hh ":" mm [ ":" ss ] space timezone
- timezone = "UT" / "GMT"
- / ( "+" / "-" ) hh mm [ space "(" zone-name ")" ]
- hh = 2digit
- mm = 2digit
- ss = 2digit
- zone-name = 1*( <ASCII printable character except ()\> / space )
-
-This is a restricted subset of the MAIL date format.
-
-If a weekday is given, it MUST be consistent with the date.
-The modern Gregorian calendar is used, and dates MUST be
-consistent with its usual conventions; for example, if the
-month is May, the day must be between 1 and 31 inclusive.
-The year SHOULD be given as four digits, and posting agents
-SHOULD enforce this; however, relayers MUST accept the two-
-digit form, and MUST interpret it as having the implicit
-prefix "19".
-
- NOTE: Two-digit year numbers can, should, and must
- be phased out by 1999.
-
-The time is given on the 24-hour clock, e.g. two hours
-before midnight is "22:00" or "22:00:00". The hh must be
-between 00 and 23 inclusive, the mm between 0 and 59 inclu-
-sive, and the ss between 0 and 61 inclusive.
-
- NOTE: Leap seconds very occasionally result in
- minutes that are 61 or 62 seconds long.
-
-INTERNET DRAFT to be NEWS sec. 5.1
-
-
-The date and time SHOULD be given in the poster's local
-timezone, including a specification of that timezone as a
-numeric offset (which SHOULD include the timezone name, e.g.
-"EST", supplied in parentheses like a MAIL comment). If
-not, they MUST be given in Universal Time (abbreviated "UT";
-"GMT" is a historical synonym for "UT"). The timezone name
-in parentheses, if present, is a comment; software MUST
-ignore it, except that reading agents might wish to display
-it to the reader. Timezone names other than "UT" and "GMT"
-MUST appear only in the comment.
-
- NOTE: Attempts to deal with a full set of timezone
- names have all foundered on the vast number of
- such names in use and the duplications (for exam-
- ple, there are at least FIVE different timezones
- called "EST" by somebody). Even the limited set
- of North American zone names authorized by MAIL is
- subject to confusion and misinterpretation. Hence
- the flat ban on non-UT timezone names except as
- comments.
-
- NOTE: RFC 1036 specified that use of GMT (aka UT,
- UTC) was preferred. However, the local time (in
- the poster's timezone) is arguably information of
- possible interest to the reader, and this requires
- some indication of the poster's timezone. Numeric
- offsets are an unambiguous way of doing this, and
- their use was indeed sanctioned by RFC 1036 (that
- is, this is a change of preference only).
-
- NOTE: There is frequent confusion, including
- errors in some news software, regarding the sign
- of numeric timezones. Zones west of Greenwich
- have negative offsets. For example, North Ameri-
- can Eastern Standard Time is zone -0500 and North
- American Eastern Daylight Time is zone -0400.
-
- NOTE: Implementors are warned that the hh in a
- timezone can go up to about 14; it is not limited
- to 12. This is because the International Date
- Line does not run exactly along the boundary
- between zone -1200 and zone +1200.
-
- NOTE: The comments in section 2.6 regarding trans-
- lation to other languages are relevant here. The
- Date-content format, and the spellings of its com-
- ponents, as found in articles themselves, are
- always as defined in this Draft, regardless of the
- language used to interact with readers and
- posters. Reading and posting agents should trans-
- late as appropriate. Actually, even English-
- language reading and posting agents will probably
- want to do some degree of translation on dates, if
- only to abbreviate the lengthy format and
-
-INTERNET DRAFT to be NEWS sec. 5.1
-
-
- (perhaps) translate to and from the reader's time-
- zone.
+ The Date header contains the date and time that the article was
+ prepared by the poster ready for transmission and SHOULD express the
+ poster's local time. The content syntax makes use of syntax defined
+ in [MESSFOR].
+
+ Date-content = date-time
+
+ NOTE: It is a useful convention to follow the date-time with a
+ comment containing the time zone in human-readable form. The use
+ of folding in a date-time is deprecated, even though permitted
+ by [MESSFOR].
+
+ In order to prevent the reinjection of expired articles into the news
+ stream, relaying and serving agents MUST refuse articles whose Date
+ header predates the earliest articles of which they normally keep
+ record, or which is more than 24 hours into the future (though they
+ MAY use a margin less than that 24 hours). Relaying agents MUST NOT
+ modify the Date header in transit.