[nSLUG] Re: DST & tzdata
mspencer at tallships.ca
Mon Mar 5 03:27:00 AST 2007
gnw> The files are tricky to read. Look for the lines:
gnw> Rule Canada 2007 max - Mar Sun>=8 2:00 1:00 D
gnw> Rule Canada 2007 max - Nov Sun>=1 2:00 0 S
gnw> and note that America/Halifax is most recently (since 1974) set to
Ah, yes. I understand that, now that I've read that section of the
tzdata file more carefully.
> After you have installed the files,...
I'm alway overcautious about "installing" stuff (as root, obviously)
when I don't fully undestand what will happen. So I unpacked the data
file in a user dir and ran "zic -d ." in various ways with confusing
results reported by zdump.
Annnd... finally figured out that zdump cannot be persuaded to dump a
particular file. It can be *tricked* into doing so by manually
renaming the relevant file in the canonical location and copying into
its place the experimentally zic-compiled file. Sigh...
gnw> $ zdump -v America/Halifax | grep 2007
gnw> America/Halifax Sun Mar 11 05:59:59 2007 UTC = Sun Mar 11 01:59:59
gnw> 2007 AST isdst=0 gmtoff=-14400
gnw> America/Halifax Sun Mar 11 06:00:00 2007 UTC = Sun Mar 11 03:00:00
gnw> 2007 ADT isdst=1 gmtoff=-10800
Right. Got that. Good. Thank you.
gnw> Do you keep your hardware clock (the one that runs from battery while
gnw> the system is off) on UTC?
So am I right in believing that I don't need all those other compiled
zoneinfo files for Ulan Bator or Tonga or even Toronto for ordinary
Michael Spencer Nova Scotia, Canada .~.
mspencer at tallships.ca /( )\
More information about the nSLUG