diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/getdate.texi | 34 |
1 files changed, 32 insertions, 2 deletions
diff --git a/doc/getdate.texi b/doc/getdate.texi index f5966bef9..07a85ced1 100644 --- a/doc/getdate.texi +++ b/doc/getdate.texi @@ -100,6 +100,34 @@ When a month is written this way, it is still considered to be written numerically, instead of being ``spelled in full''; this changes the allowed strings. +@cindex language, in dates +In the current implementation, only English is supported for words and +abbreviations like @samp{AM}, @samp{DST}, @samp{EST}, @samp{first}, +@samp{January}, @samp{Sunday}, @samp{tomorrow}, and @samp{year}. + +@cindex language, in dates +@cindex time zone item +The output of @command{date} 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 +@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 +ways to do this: + +@example +$ LC_ALL=C TZ=UTC0 date +Fri Dec 15 19:48:05 UTC 2000 +$ TZ=UTC0 date +"%Y-%m-%d %H:%M:%SZ" +2000-12-15 19:48:05Z +$ date --iso-8601=seconds # a GNU extension +2000-12-15T11:48:05-0800 +$ date --rfc-822 # a GNU extension +Fri, 15 Dec 2000 11:48:05 -0800 +$ date +"%Y-%m-%d %H:%M:%S %z" # %z is a GNU extension. +2000-12-15 11:48:05 -0800 +@end example + @cindex case, ignored in dates @cindex comments, in dates Alphabetic case is completely ignored in dates. Comments may be introduced @@ -238,13 +266,15 @@ but not both. @cindex time zone item A @dfn{time zone item} specifies an international time zone, indicated -by a small set of letters, e.g., @samp{UTC} for Coordinated Universal +by a small set of letters, e.g., @samp{UTC} or @samp{Z} +for Coordinated Universal Time. Any included periods are ignored. By following a non-daylight-saving time zone by the string @samp{DST} in a separate word (that is, separated by some white space), the corresponding daylight saving time zone may be specified. -Time zone items are obsolescent and are not recommended, because they +Time zone items other than @samp{UTC} and @samp{Z} +are obsolescent and are not recommended, because they are ambiguous; for example, @samp{EST} has a different meaning in Australia than in the United States. Instead, it's better to use unambiguous numeric time zone corrections like @samp{-0500}, as |