Timezone Europe/Dublin has DST flag set in winter
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SUSE Linux Enterprise 12 SP4 and later
SUSE Linux Enterprise 15 since timezone-2018e
SUSE Linux Enterprise 15 SP1 and later
# zdump -c 2023,2024 -v Europe/Dublin | grep 2023 Europe/Dublin Sun Mar 26 00:59:59 2023 UT = Sun Mar 26 00:59:59 2023 GMT isdst=1 gmtoff=0 Europe/Dublin Sun Mar 26 01:00:00 2023 UT = Sun Mar 26 02:00:00 2023 IST isdst=0 gmtoff=3600 Europe/Dublin Sun Oct 29 00:59:59 2023 UT = Sun Oct 29 01:59:59 2023 IST isdst=0 gmtoff=3600 Europe/Dublin Sun Oct 29 01:00:00 2023 UT = Sun Oct 29 01:00:00 2023 GMT isdst=1 gmtoff=0
# zdump -c 2023,2024 -v Europe/Belfast | grep 2023 Europe/Belfast Sun Mar 26 00:59:59 2023 UT = Sun Mar 26 00:59:59 2023 GMT isdst=0 gmtoff=0 Europe/Belfast Sun Mar 26 01:00:00 2023 UT = Sun Mar 26 02:00:00 2023 BST isdst=1 gmtoff=3600 Europe/Belfast Sun Oct 29 00:59:59 2023 UT = Sun Oct 29 01:59:59 2023 BST isdst=1 gmtoff=3600 Europe/Belfast Sun Oct 29 01:00:00 2023 UT = Sun Oct 29 01:00:00 2023 GMT isdst=0 gmtoff=0
Note that the offset to UTC (tm_gmtoff) is the same at all times in both Dublin and Belfast.
There is another, subtle difference regarding the global variable timezone(3): it is -3600 for
Europe/Dublin (but, as expected, 0 for Europe/Belfast).
According to https://www.gnu.org/software/libc/manual/html_node/Time-Zone-Functions.html , long timezone "contains the difference between UTC and the latest local standard time, in seconds west of UTC. For example, in the U.S. Eastern time zone, the value is 5*60*60. Unlike the tm_gmtoff member of the broken-down time structure, this value is not adjusted for daylight saving, and its sign is reversed. In GNU programs it is better to use tm_gmtoff, since it contains the correct offset even when it is not the latest one."
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- Document ID:000020913
- Creation Date: 05-Jan-2023
- Modified Date:10-Jan-2023
- SUSE Linux Enterprise Desktop
- SUSE Linux Enterprise Server
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