Re: calendar gets wrong end for Daylight Savings Time

[James Cloos]

>>>>> "GM" == Glenn Morris <address@hidden> writes:

GM> Extracting the information directly from the tz database (which must
GM> contain it, in some format) would require less CPU, but more of my CPU
GM> to figure out how to do it (especially in a system-portable way).

zdump(8) gives a textual dump of a given timezone when passed the -v
flag.  If that is available on all platforms it should do.

As an example, this is what it outputs for America/Phoenix:

,----
| :; zdump -v America/Phoenix
| America/Phoenix  Fri Dec 13 20:45:52 1901 UTC = Fri Dec 13 13:45:52 1901 MST 
isdst=0
| America/Phoenix  Sat Dec 14 20:45:52 1901 UTC = Sat Dec 14 13:45:52 1901 MST 
isdst=0
| America/Phoenix  Sun Mar 31 08:59:59 1918 UTC = Sun Mar 31 01:59:59 1918 MST 
isdst=0
| America/Phoenix  Sun Mar 31 09:00:00 1918 UTC = Sun Mar 31 03:00:00 1918 MDT 
isdst=1
| America/Phoenix  Sun Oct 27 07:59:59 1918 UTC = Sun Oct 27 01:59:59 1918 MDT 
isdst=1
| America/Phoenix  Sun Oct 27 08:00:00 1918 UTC = Sun Oct 27 01:00:00 1918 MST 
isdst=0
| America/Phoenix  Sun Mar 30 08:59:59 1919 UTC = Sun Mar 30 01:59:59 1919 MST 
isdst=0
| America/Phoenix  Sun Mar 30 09:00:00 1919 UTC = Sun Mar 30 03:00:00 1919 MDT 
isdst=1
| America/Phoenix  Sun Oct 26 07:59:59 1919 UTC = Sun Oct 26 01:59:59 1919 MDT 
isdst=1
| America/Phoenix  Sun Oct 26 08:00:00 1919 UTC = Sun Oct 26 01:00:00 1919 MST 
isdst=0
| America/Phoenix  Mon Feb  9 08:59:59 1942 UTC = Mon Feb  9 01:59:59 1942 MST 
isdst=0
| America/Phoenix  Mon Feb  9 09:00:00 1942 UTC = Mon Feb  9 03:00:00 1942 MWT 
isdst=1
| America/Phoenix  Sat Jan  1 06:00:59 1944 UTC = Sat Jan  1 00:00:59 1944 MWT 
isdst=1
| America/Phoenix  Sat Jan  1 06:01:00 1944 UTC = Fri Dec 31 23:01:00 1943 MST 
isdst=0
| America/Phoenix  Sat Apr  1 07:00:59 1944 UTC = Sat Apr  1 00:00:59 1944 MST 
isdst=0
| America/Phoenix  Sat Apr  1 07:01:00 1944 UTC = Sat Apr  1 01:01:00 1944 MWT 
isdst=1
| America/Phoenix  Sun Oct  1 06:00:59 1944 UTC = Sun Oct  1 00:00:59 1944 MWT 
isdst=1
| America/Phoenix  Sun Oct  1 06:01:00 1944 UTC = Sat Sep 30 23:01:00 1944 MST 
isdst=0
| America/Phoenix  Sun Apr 30 08:59:59 1967 UTC = Sun Apr 30 01:59:59 1967 MST 
isdst=0
| America/Phoenix  Sun Apr 30 09:00:00 1967 UTC = Sun Apr 30 03:00:00 1967 MDT 
isdst=1
| America/Phoenix  Sun Oct 29 07:59:59 1967 UTC = Sun Oct 29 01:59:59 1967 MDT 
isdst=1
| America/Phoenix  Sun Oct 29 08:00:00 1967 UTC = Sun Oct 29 01:00:00 1967 MST 
isdst=0
| America/Phoenix  Mon Jan 18 03:14:07 2038 UTC = Sun Jan 17 20:14:07 2038 MST 
isdst=0
| America/Phoenix  Tue Jan 19 03:14:07 2038 UTC = Mon Jan 18 20:14:07 2038 MST 
isdst=0
`----

-JimC
-- 
James Cloos <address@hidden>         OpenPGP: 0xED7DAEA6