id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
3336,utc offset calculated wrong,silvan@…,az_sw_dude,"Boost seems to invert the posix time zone specs or even worse to calculate them completely wrong:

[http://www.opengroup.org/onlinepubs/000095399/basedefs/xbd_chap08.html]

states:

""If preceded by a '-', the timezone shall be east of the Prime Meridian; otherwise, it shall be west (which may be indicated by an optional preceding '+' ).""

Using the following lines in a c++ program:

{{{
  time_zone_ptr myzone(new posix_time_zone(string(""CET-1CEST,M3.5.0,M10.5.0/3""))); // e.g. Europe/Berlin
  cout << ""Posix time string: "" << myzone->to_posix_string() << endl;
  local_date_time mylocaltime(date(2009,8,11), time_duration(17,0,0), myzone, true);
  cout << ""Wall clock: "" << mylocaltime.local_time() << endl;
  cout << ""Time in UTC: "" << mylocaltime.utc_time() << endl;
}}}

gives following output: [[BR]]
Posix time string: CET-01CEST+01,M3.5.0/02:00,M10.5.0/03:00 [[BR]]
Wall clock: 2009-Aug-11 17:00:00 [[BR]]
Time in UTC: 2009-Aug-11 17:00:00 [[BR]]

The system I used: Debian GNU/Linux squeeze/sid [[BR]]
uname -a[[BR]]
Linux fafner 2.6.28.7 #1 SMP Mon Mar 16 17:39:15 CET 2009 i686 GNU/Linux

output from date:[[BR]]
date -d ""2009-8-11 17:00 CEST ""[[BR]]
Di 11. Aug 17:00:00 CEST 2009[[BR]]
date -d ""2009-8-11 17:00 CEST "" -u[[BR]]
Di 11. Aug 15:00:00 UTC 2009

Libraries (debian):
libboost-date-time1.38.0
libboost-date-time1.38-dev
libboost-date-time-dev

The time zone spec ist taken from /usr/share/zoneinfo/CET on my system.",Bugs,new,Boost 1.57.0,date_time,Boost 1.54.0,Problem,,,