X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=doc%2Fparse-datetime.texi;h=f17b6b444f3851a0771b61fbaf6361530d96fd85;hb=0815bd3d34b072659e4e2c8c97241fe2ccae1cd6;hp=2f1ab34ec5ec7a6e2eaef98415ea4850a3a45aec;hpb=d60f3b0c6b0f93a601acd1cfd3923f94ca05abb0;p=gnulib.git

diff --git a/doc/parse-datetime.texi b/doc/parse-datetime.texi
index 2f1ab34ec..f17b6b444 100644
--- a/doc/parse-datetime.texi
+++ b/doc/parse-datetime.texi
@@ -1,6 +1,6 @@
 @c GNU date syntax documentation
 
-@c Copyright (C) 1994-2006, 2009-2011 Free Software Foundation, Inc.
+@c Copyright (C) 1994-2006, 2009-2012 Free Software Foundation, Inc.
 
 @c Permission is granted to copy, distribute and/or modify this document
 @c under the terms of the GNU Free Documentation License, Version 1.3 or
@@ -51,6 +51,7 @@ arguments to the various programs.  The C interface (via the
 * Calendar date items::            19 Dec 1994.
 * Time of day items::              9:20pm.
 * Time zone items::                @sc{est}, @sc{pdt}, @sc{gmt}.
+* Combined date and time of day items:: 1972-09-24T20:02:00,000000-0500
 * Day of week items::              Monday and others.
 * Relative items in date strings:: next tuesday, 2 years ago.
 * Pure numbers in date strings::   19931219, 1440.
@@ -76,6 +77,7 @@ many flavors of items:
 @item calendar date items
 @item time of day items
 @item time zone items
+@item combined date and time of day items
 @item day of the week items
 @item relative items
 @item pure numbers.
@@ -115,10 +117,10 @@ abbreviations like @samp{AM}, @samp{DST}, @samp{EST}, @samp{first},
 The output of the @command{date} command
 is not always acceptable as a date string,
 not only because of the language problem, but also because there is no
-standard meaning for time zone items like @samp{IST}.  When using
+standard meaning for time zone items like @samp{IST}@.  When using
 @command{date} to generate a date string intended to be parsed later,
 specify a date format that is independent of language and that does not
-use time zone items other than @samp{UTC} and @samp{Z}.  Here are some
+use time zone items other than @samp{UTC} and @samp{Z}@.  Here are some
 ways to do this:
 
 @example
@@ -126,8 +128,8 @@ $ LC_ALL=C TZ=UTC0 date
 Mon Mar  1 00:21:42 UTC 2004
 $ TZ=UTC0 date +'%Y-%m-%d %H:%M:%SZ'
 2004-03-01 00:21:42Z
-$ date --iso-8601=ns | tr T ' '  # --iso-8601 is a GNU extension.
-2004-02-29 16:21:42,692722128-0800
+$ date --rfc-3339=ns  # --rfc-3339 is a GNU extension.
+2004-02-29 16:21:42.692722128-08:00
 $ date --rfc-2822  # a GNU extension
 Sun, 29 Feb 2004 16:21:42 -0800
 $ date +'%Y-%m-%d %H:%M:%S %z'  # %z is a GNU extension.
@@ -143,6 +145,7 @@ between round parentheses, as long as included parentheses are properly
 nested.  Hyphens not followed by a digit are currently ignored.  Leading
 zeros on numbers are ignored.
 
+@cindex leap seconds
 Invalid dates like @samp{2005-02-29} or times like @samp{24:00} are
 rejected.  In the typical case of a host that does not support leap
 seconds, a time like @samp{23:59:60} is rejected even if it
@@ -235,6 +238,7 @@ day.  Here are some examples, all of which represent the same time:
 20:02-0500      # In @sc{est} (U.S. Eastern Standard Time).
 @end example
 
+@cindex leap seconds
 More generally, the time of day may be given as
 @samp{@var{hour}:@var{minute}:@var{second}}, where @var{hour} is
 a number between 0 and 23, @var{minute} is a number between 0 and
@@ -311,6 +315,29 @@ time stamps are interpreted using the rules of the default time zone
 (@pxref{Specifying time zone rules}).
 
 
+@node Combined date and time of day items
+@section Combined date and time of day items
+
+@cindex combined date and time of day item
+
+A @dfn{combined date and time of day item} specifies the time on a
+specific day of the year.  This type is needed for formats that cannot
+be represented by individual calendar date (@pxref{Calendar date items})
+and time of day (@pxref{Time of day items}) items due to ambiguity.
+
+@example
+# ISO 8601 extended date and time of day format
+1972-09-24T20:02:00,000000-0500
+@end example
+
+@cindex @sc{iso} 8601 date and time of day format
+@cindex date and time of day format, @sc{iso} 8601
+
+The @sc{iso} 8601 extended date and time of day format is an @sc{iso}
+8601 date, a @samp{T} character separator, followed by an @sc{iso} 8601 time
+of day.
+
+
 @node Day of week items
 @section Day of week items
 
@@ -455,15 +482,15 @@ supported by the internal representation is truncated toward minus
 infinity.  Such a number cannot be combined with any other date
 item, as it specifies a complete time stamp.
 
-@cindex beginning of time, for @acronym{POSIX}
-@cindex epoch, for @acronym{POSIX}
+@cindex beginning of time, for POSIX
+@cindex epoch, for POSIX
 Internally, computer times are represented as a count of seconds since
-an epoch---a well-defined point of time.  On @acronym{GNU} and
-@acronym{POSIX} systems, the epoch is 1970-01-01 00:00:00 @sc{utc}, so
+an epoch---a well-defined point of time.  On GNU and
+POSIX systems, the epoch is 1970-01-01 00:00:00 @sc{utc}, so
 @samp{@@0} represents this time, @samp{@@1} represents 1970-01-01
-00:00:01 @sc{utc}, and so forth.  @acronym{GNU} and most other
-@acronym{POSIX}-compliant systems support such times as an extension
-to @acronym{POSIX}, using negative counts, so that @samp{@@-1}
+00:00:01 @sc{utc}, and so forth.  GNU and most other
+POSIX-compliant systems support such times as an extension
+to POSIX, using negative counts, so that @samp{@@-1}
 represents 1969-12-31 23:59:59 @sc{utc}.
 
 Traditional Unix systems count seconds with 32-bit two's-complement
@@ -472,6 +499,7 @@ integers and can represent times from 1901-12-13 20:45:52 through
 of seconds with nanosecond subcounts, and can represent all the times
 in the known lifetime of the universe to a resolution of 1 nanosecond.
 
+@cindex leap seconds
 On most hosts, these counts ignore the presence of leap seconds.
 For example, on most hosts @samp{@@915148799} represents 1998-12-31
 23:59:59 @sc{utc}, @samp{@@915148800} represents 1999-01-01 00:00:00
@@ -491,7 +519,7 @@ two quote characters (@samp{"}) must be present in the date, and any
 quotes or backslashes within @var{rule} must be escaped by a
 backslash.
 
-For example, with the @acronym{GNU} @command{date} command you can
+For example, with the GNU @command{date} command you can
 answer the question ``What time is it in New York when a Paris clock
 shows 6:30am on October 31, 2004?'' by using a date beginning with
 @samp{TZ="Europe/Paris"} as shown in the following shell transcript:
@@ -515,16 +543,16 @@ A @env{TZ} value is a rule that typically names a location in the
 @uref{http://www.twinsun.com/tz/tz-link.htm, @samp{tz} database}.
 A recent catalog of location names appears in the
 @uref{http://twiki.org/cgi-bin/xtra/tzdate, TWiki Date and Time
-Gateway}.  A few non-@acronym{GNU} hosts require a colon before a
+Gateway}.  A few non-GNU hosts require a colon before a
 location name in a @env{TZ} setting, e.g.,
 @samp{TZ=":America/New_York"}.
 
 The @samp{tz} database includes a wide variety of locations ranging
 from @samp{Arctic/Longyearbyen} to @samp{Antarctica/South_Pole}, but
 if you are at sea and have your own private time zone, or if you are
-using a non-@acronym{GNU} host that does not support the @samp{tz}
-database, you may need to use a @acronym{POSIX} rule instead.  Simple
-@acronym{POSIX} rules like @samp{UTC0} specify a time zone without
+using a non-GNU host that does not support the @samp{tz}
+database, you may need to use a POSIX rule instead.  Simple
+POSIX rules like @samp{UTC0} specify a time zone without
 daylight saving time; other rules can specify simple daylight saving
 regimes.  @xref{TZ Variable,, Specifying the Time Zone with @code{TZ},
 libc, The GNU C Library}.
@@ -560,4 +588,4 @@ file, and lacks the thread-safety of @code{parse_datetime}.
 @cindex Berry, K.
 This chapter was originally produced by Fran@,{c}ois Pinard
 (@email{pinard@@iro.umontreal.ca}) from the @file{parse_datetime.y} source code,
-and then edited by K.@: Berry (@email{kb@@cs.umb.edu}).
+and then edited by K. Berry (@email{kb@@cs.umb.edu}).