On 2014-09-14 22:40, "" wrote:
Looks like isdst should be 1 on Europe/London Sat Oct 26 23:00:00 1968 and Europe/London Sun Oct 31 01:59:59 1971 zdump -v -c 1968,1973 Europe/London Europe/London -9223372036854775808 = NULL Europe/London -9223372036854689408 = NULL Europe/London Sun Feb 18 01:59:59 1968 UT = Sun Feb 18 01:59:59 1968 GMT isdst=0 gmtoff=0 Europe/London Sun Feb 18 02:00:00 1968 UT = Sun Feb 18 03:00:00 1968 BST isdst=1 gmtoff=3600 Europe/London Sat Oct 26 22:59:59 1968 UT = Sat Oct 26 23:59:59 1968 BST isdst=1 gmtoff=3600 Europe/London Sat Oct 26 23:00:00 1968 UT = Sun Oct 27 00:00:00 1968 BST isdst=0 gmtoff=3600 Europe/London Sun Oct 31 01:59:59 1971 UT = Sun Oct 31 02:59:59 1971 BST isdst=0 gmtoff=3600 Europe/London Sun Oct 31 02:00:00 1971 UT = Sun Oct 31 02:00:00 1971 GMT isdst=0 gmtoff=0 Europe/London Sun Mar 19 01:59:59 1972 UT = Sun Mar 19 01:59:59 1972 GMT isdst=0 gmtoff=0 Europe/London Sun Mar 19 02:00:00 1972 UT = Sun Mar 19 03:00:00 1972 BST isdst=1 gmtoff=3600 Europe/London Sun Oct 29 01:59:59 1972 UT = Sun Oct 29 02:59:59 1972 BST isdst=1 gmtoff=3600 Europe/London Sun Oct 29 02:00:00 1972 UT = Sun Oct 29 02:00:00 1972 GMT isdst=0 gmtoff=0 Europe/London 9223372036854689407 = NULL Europe/London 9223372036854775807 = NULL
The relevant rules, comments, and zones to examine in data/europe are: # Summer Time Order, 1968 (S.I. 1968/117) Rule GB-Eire 1968 only - Feb 18 2:00s 1:00 BST # The British Standard Time Act, 1968 # (no summer time) # The Summer Time Act, 1972 Rule GB-Eire 1972 1980 - Mar Sun>=16 2:00s 1:00 BST Rule GB-Eire 1972 1980 - Oct Sun>=23 2:00s 0 GMT and: # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/London -0:01:15 - LMT 1847 Dec 1 0:00s 0:00 GB-Eire %s 1968 Oct 27 1:00 - BST 1971 Oct 31 2:00u which gives 1968 Oct 27 midnight as the transition from British Summer Time isdst=1 to British Standard Time isdst=0 both with GMT offset +1.00, from the British Standard Time Act 1968 c. 45, whichended itself effective 1971 Oct 31 2.00 GMT. See http://polyomino.org.uk/british-time and search for "1968 c. 45". -- Take care. Thanks, Brian Inglis