Some feedback - 1. This is another idea for supporting dates into the far future. Is it feasible for zic to encode variable information in the data file for the last set of rules, that would be used for times past the last entry in the transition table? Then localtime() would use the variables algorithmically rather than using table-driven data, for dates past the last table entry. Perhaps set a minimum size for the table entries (ie, have table entries at least up to year xxxx.) zic would effectively map the last set of transition rules of an Olson timezone to an equivalent POSIX timezone. 2. I'm not sure yet, but with 9x larger timezone binaries, Sun might retain the old-style timezone binaries for timezone patch updates. If so, it might be useful if zic has an option to produce old-style timezone binaries. 3. POSIX timezone 64-bit time_t support It seems the new localtime.c does not support 64-bit dates for POSIX timezones. Will this be supported? Thanks, Robbin
Date: Thu, 21 Apr 2005 15:24:10 -0400 (EDT) From: Arthur David Olson <olsona@lecserver.nci.nih.gov> To: tz@lecserver.nci.nih.gov Subject: Proposed 64-bit changes
Below are diffs to the time zone code to cope with 64-bit time_t systems; these reflect suggestions I've received to date. Absent negative feedback, I'll update the ftp versions on May 2, 2005.
For #1, that's exactly what we do in ICU, since we have to convert all times covered by the Java Date. So we generate extra information for the rules covering the last year, that we apply algorithmically into the indefinite future. We would strongly support adding the ability to generate that data to zic, and could contribute some code for doing it. Mark ----- Original Message ----- From: "Robbin Kawabata" <Robbin.Kawabata@eng.sun.com> To: <olsona@lecserver.nci.nih.gov>; <tz@lecserver.nci.nih.gov> Cc: <robbin.kawabata@sun.com> Sent: Friday, April 29, 2005 13:59 Subject: Re: Proposed 64-bit changes
Some feedback -
1. This is another idea for supporting dates into the far future. Is it feasible for zic to encode variable information in the data file for the last set of rules, that would be used for times past the last entry in the transition table? Then localtime() would use the variables algorithmically rather than using table-driven data, for dates past the last table entry. Perhaps set a minimum size for the table entries (ie, have table entries at least up to year xxxx.)
zic would effectively map the last set of transition rules of an Olson timezone to an equivalent POSIX timezone.
2. I'm not sure yet, but with 9x larger timezone binaries, Sun might retain the old-style timezone binaries for timezone patch updates. If so, it might be useful if zic has an option to produce old-style timezone binaries.
3. POSIX timezone 64-bit time_t support It seems the new localtime.c does not support 64-bit dates for POSIX timezones. Will this be supported?
Thanks, Robbin
Date: Thu, 21 Apr 2005 15:24:10 -0400 (EDT) From: Arthur David Olson <olsona@lecserver.nci.nih.gov> To: tz@lecserver.nci.nih.gov Subject: Proposed 64-bit changes
Below are diffs to the time zone code to cope with 64-bit time_t systems; these reflect suggestions I've received to date. Absent negative feedback, I'll update the ftp versions on May 2, 2005.
Robbin Kawabata <Robbin.Kawabata@eng.sun.com> writes:
Is it feasible for zic to encode variable information in the data file for the last set of rules, that would be used for times past the last entry in the transition table? Then localtime() would use the variables algorithmically rather than using table-driven data, for dates past the last table entry.
Hmm, how would that be an improvement on the proposed system? As I understand it, the proposed system algorithmically generates time stamps from the last 400 years in the table. This assumes a Gregorian calendar, which isn't correct in general (e.g., Iran), but it can't be worse than any POSIX-based prediction.
it might be useful if zic has an option to produce old-style timezone binaries.
Yes, that makes sense to me too.
participants (3)
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Mark Davis -
Paul Eggert -
Robbin Kawabata