POSIX and summer savings time

I have a time stamp in UTC (GMT) time:

 >  format(ISOdatetime(1970,1,1,0,0,0)+1165398135729/1000,"%Y-%m-%d 
%H:%M:%OS3")

"2006-12-06 09:42:18.823"  (note millisecond accuracy, but not relevant 
to question here)

Now, this time stamp actually "happened" at local (Swedish) time one 
hour later (10:42).

Regarding summer/winter adjustments in time ("spring forward, fall 
back"):   Is there a way of automatically recovering the local time 
adjustments for a given date?  E.g., a date/time in springtime = GMT +2 
, else GMT +1

Thanks,

Derek Eder

Derek N. Eder

Gothenburg University 
VINKLA - Vigilance and Neurocognition laboratory 

SU/Sahlgrenska
Utvecklingslab 1, Med
Gr?na str?ket 8
SE 413 45 G?teborg (Gothenburg)
Sverige (Sweden)

+46 (031)* 342 8261 (28261 inom Sahlgrenska)
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