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authorPaul Eggert <eggert@cs.ucla.edu>2022-07-13 18:54:56 -0700
committerPaul Eggert <eggert@cs.ucla.edu>2022-07-13 18:54:56 -0700
commit5336cb27ab42f27b8b8ac31982e8215fe5af6f34 (patch)
treecaa7534b016de14d4c189418f61171c1891bac78 /doc
parentf65d00ebacc891e57cca729041d028d07d1883bb (diff)
downloadgnulib-5336cb27ab42f27b8b8ac31982e8215fe5af6f34.tar.gz
* doc/parse-datetime.texi: Tweak wording again.
Diffstat (limited to 'doc')
-rw-r--r--doc/parse-datetime.texi17
1 files changed, 10 insertions, 7 deletions
diff --git a/doc/parse-datetime.texi b/doc/parse-datetime.texi
index 7939273691..e1ce97220a 100644
--- a/doc/parse-datetime.texi
+++ b/doc/parse-datetime.texi
@@ -551,31 +551,34 @@ 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
+from @samp{Africa/Abidjan} to @samp{Pacific/Tongatapu}, but
if you are at sea and have your own private time zone, or if you are
using a non-GNU host that does not support the @samp{tz}
database, you may need to use a POSIX rule instead.
The previously-mentioned POSIX rule @samp{UTC0} says that the time zone
abbreviation is @samp{UTC}, the zone is zero hours away from
Greenwich, and there is no daylight saving time.
-Simple POSIX rules like this can also specify nonzero Greenwich offsets.
+POSIX rules can also specify nonzero Greenwich offsets.
For example, the following shell transcript answers the question
``What time is it five and a half hours east of Greenwich when a clock
seven hours west of Greenwich shows 9:50pm on July 12, 2022?''
@example
-$ TZ="<+0530>-5:30" date --date='TZ="<-07>7" 2022-07-12 21:50'
+$ TZ="<+0530>-5:30" date --date='TZ="<-07>+7" 2022-07-12 21:50'
Wed Jul 13 10:20:00 +0530 2022
@end example
@noindent
-This example uses the somewhat-confusing POSIX convention for TZ strings.
-@samp{TZ="<-07>7"} says that the time zone abbreviation is @samp{-07}
+This example uses the somewhat-confusing POSIX convention for rules.
+@samp{TZ="<-07>+7"} says that the time zone abbreviation is @samp{-07}
and the time zone is 7 hours west of Greenwich, and
@samp{TZ="<+0530>-5:30"} says that the time zone abbreviation is @samp{+0530}
and the time zone is 5 hours 30 minutes east of Greenwich.
-More-complex POSIX TZ strings can specify simple daylight saving
-regimes. @xref{TZ Variable,, Specifying the Time Zone with @code{TZ},
+Although trickier POSIX @env{TZ} settings like
+@samp{TZ="<-05>+5<-04>,M3.2.0/2,M11.1.0/2"} can specify some daylight
+saving regimes, location-based settings like
+@samp{TZ="America/New_York"} are typically simpler and more accurate
+historically. @xref{TZ Variable,, Specifying the Time Zone with @code{TZ},
libc, The GNU C Library}.
@node Authors of parse_datetime