[Python-checkins] python/dist/src/Doc/lib libtime.tex,1.56,1.57

[nnorwitz@users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Doc/lib
In directory sc8-pr-cvs1:/tmp/cvs-serv5600/Doc/lib

Modified Files:
	libtime.tex 
Log Message:
SF #735051, add time.tzset documentation


Index: libtime.tex
===================================================================
RCS file: /cvsroot/python/python/dist/src/Doc/lib/libtime.tex,v
retrieving revision 1.56
retrieving revision 1.57
diff -C2 -d -r1.56 -r1.57
*** libtime.tex	5 May 2003 16:46:26 -0000	1.56
--- libtime.tex	8 Jun 2003 13:57:19 -0000	1.57
***************
*** 325,328 ****
--- 325,424 ----
  \end{datadesc}
  
+ \begin{funcdesc}{tzset}{}
+ Resets the time conversion rules used by the library routines.
+ The environment variable \envvar{TZ} specifies how this is done.
+ \versionadded{2.3}
+ 
+ Availability: \UNIX.
+ 
+ \begin{notice}
+ Although in many cases, changing the \envvar{TZ} environment variable
+ may affect the output of functions like \function{localtime} without calling 
+ \function{tzset}, this behavior should not be relied on.
+ 
+ The \envvar{TZ} environment variable should contain no whitespace.
+ \end{notice}
+ 
+ The standard format of the \envvar{TZ} environment variable is:
+ (whitespace added for clarity)
+ \begin{itemize}
+     \item[std offset [dst [offset] [,start[/time], end[/time]]]]
+ \end{itemize}
+ 
+ Where:
+ 
+ \begin{itemize}
+   \item[std and dst]
+     Three or more alphanumerics giving the timezone abbreviations.
+     These will be propogated into time.tzname
+ 
+   \item[offset]
+     The offset has the form: \plusminus hh[:mm[:ss]].
+     This indicates the value added the local time to arrive at UTC. 
+     If preceded by a '-', the timezone is east of the Prime 
+     Meridian; otherwise, it is west. If no offset follows
+     dst, summmer time is assumed to be one hour ahead of standard time.
+ 
+   \item[start[/time],end[/time]]
+     Indicates when to change to and back from DST. The format of the
+     start and end dates are one of the following:
+ 
+     \begin{itemize}
+       \item[J\var{n}]
+         The Julian day \var{n} (1 <= \var{n} <= 365). Leap days are not 
+         counted, so in all years February 28 is day 59 and
+         March 1 is day 60.
+ 
+     \item[\var{n}]
+         The zero-based Julian day (0 <= \var{n} <= 365). Leap days are
+         counted, and it is possible to refer to February 29.
+ 
+       \item[M\var{m}.\var{n}.\var{d}]
+         The \var{d}'th day (0 <= \var{d} <= 6) or week \var{n} 
+         of month \var{m} of the year (1 <= \var{n} <= 5, 
+         1 <= \var{m} <= 12, where week 5 means "the last \var{d} day
+         in month \var{m}" which may occur in either the fourth or 
+         the fifth week). Week 1 is the first week in which the 
+         \var{d}'th day occurs. Day zero is Sunday.
+     \end{itemize}
+ 
+     time has the same format as offset except that no leading sign ('-' or
+     '+') is allowed. The default, if time is not given, is 02:00:00.
+ \end{itemize}
+ 
+ 
+ \begin{verbatim}
+ >>> os.environ['TZ'] = 'EST+05EDT,M4.1.0,M10.5.0'
+ >>> time.tzset()
+ >>> time.strftime('%X %x %Z')
+ '02:07:36 05/08/03 EDT'
+ >>> os.environ['TZ'] = 'AEST-10AEDT-11,M10.5.0,M3.5.0'
+ >>> time.tzset()
+ >>> time.strftime('%X %x %Z')
+ '16:08:12 05/08/03 AEST'
+ \end{verbatim}
+ 
+ On many Unix systems (including *BSD, Linux, Solaris, and Darwin), it
+ is more convenient to use the system's zoneinfo (\manpage{tzfile}{5}) 
+ database to specify the timezone rules. To do this, set the 
+ \envvar{TZ} environment variable to the path of the required timezone 
+ datafile, relative to the root of the systems 'zoneinfo' timezone database,
+ usually located at \file{/usr/share/zoneinfo}. For example, 
+ \code{'US/Eastern'}, \code{'Australia/Melbourne'}, \code{'Egypt'} or 
+ \code{'Europe/Amsterdam'}.
+ 
+ \begin{verbatim}
+ >>> os.environ['TZ'] = 'US/Eastern'
+ >>> time.tzset()
+ >>> time.tzname
+ ('EST', 'EDT')
+ >>> os.environ['TZ'] = 'Egypt'
+ >>> time.tzset()
+ >>> time.tzname
+ ('EET', 'EEST')
+ \end{verbatim}
+ 
+ \end{funcdesc}
+ 
  
  \begin{seealso}