From: Guido van Rossum Date: Tue, 9 Jun 1998 21:25:41 +0000 (+0000) Subject: Added notes about epochs, the year 2038, and a small Y2K disclaimer X-Git-Tag: v1.5.2a1~495 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=929bd0e02e0fd3062db0ad08443dbfd2846f1f8c;p=python Added notes about epochs, the year 2038, and a small Y2K disclaimer (all with index entries!). Also update the list of functions that take or yield a time represented as a 9-tuple. --- diff --git a/Doc/lib/libtime.tex b/Doc/lib/libtime.tex index 483469d86d..711347b30b 100644 --- a/Doc/lib/libtime.tex +++ b/Doc/lib/libtime.tex @@ -13,7 +13,21 @@ An explanation of some terminology and conventions is in order. The \dfn{epoch}\index{epoch} is the point where the time starts. On January 1st of that year, at 0 hours, the ``time since the epoch'' is zero. For \UNIX{}, the epoch is 1970. To find out what the epoch is, -look at \code{gmtime(0)}. +look at \code{gmtime(0)}.% +\index{epoch} + +\item +The functions in this module don't handle dates and times before the +epoch or far in the future. The cut-off point in the future is +determined by the C library; for \UNIX{}, it is typically in 2038.% +\index{Year 2038} + +\item +Year 2000 (Y2K) issues: Python depends on the platform's C library, +which generally doesn't have year 2000 issues, since all dates and +times are represented internally as seconds since the epoch.% +\index{Year 2000}% +\index{Y2K} \item UTC is Coordinated Universal Time (formerly known as Greenwich Mean @@ -48,8 +62,9 @@ nonzero fraction (\UNIX{} \cfunction{select()} is used to implement this, where available). \item -The time tuple as returned by \function{gmtime()} and -\function{localtime()}, or as accpted by \function{mktime()} is a +The time tuple as returned by \function{gmtime()}, +\function{localtime()}, and \function{strptime()}, and accepted by +\function{asctime()}, \function{mktime()} and \function{strftime()}, is a tuple of 9 integers: year (e.g.\ 1993), month (1--12), day (1--31), hour (0--23), minute (0--59), second (0--59), weekday (0--6, monday is 0), Julian day (1--366) and daylight savings flag (-1, 0 or 1). @@ -99,7 +114,7 @@ Nonzero if a DST timezone is defined. \begin{funcdesc}{gmtime}{secs} Convert a time expressed in seconds since the epoch to a time tuple in UTC in which the dst flag is always zero. Fractions of a second are -ignored. +ignored. See above for a description of the tuple lay-out. \end{funcdesc} \begin{funcdesc}{localtime}{secs}