[gdal-dev] Design for sub-second accuracy in OGR ?

[Even Rouault]

Le mardi 07 avril 2015 01:15:17, Mike Toews a écrit :
> On 6 April 2015 at 09:39, Even Rouault <even.rouault at spatialys.com> wrote:
> > I should have mentionned what currently exists indeed :
> >     struct {
> >     
> >         GInt16  Year;
> >         GByte   Month;
> >         GByte   Day;
> >         GByte   Hour;
> >         GByte   Minute;
> >         GByte   Second;
> >         GByte   TZFlag; /* 0=unknown, 1=localtime(ambiguous),
> >         
> >                            100=GMT, 104=GMT+1, 80=GMT-5, etc */
> >     
> >     } Date;
> 
> In regards to TZFlag, it should also be used to optionally convey
> daylight savings information, where known. E.g. see the 'is_dst' in
> struct tm [1]. I'm not sure if a GMT value can adequately convey this,
> but correct me if it can.

Mike,

I think daylight savings information is captured in the timezone (e.g local 
time in France is GMT+2 now, and GMT+1 during winter). None of the formats 
that convey datetime have a flag to indicate if DST is on/off.

Even

-- 
Spatialys - Geospatial professional services
http://www.spatialys.com