- tz - lists.iana.org

FW: America/Chicago zone vs mktime w/tm_isdst!=-1
by Olson, Arthur David (NIH/NCI) Dec. 6, 2003

Dec. 6, 2003

Dan Nelson is not on the time zone mailing list; direct replies appropriately. --ado -----Original Message----- From: Dan Nelson [mailto:dnelson@allantgroup.com] Sent: Monday, November 24, 2003 6:23 PM To: tz(a)lecserver.nci.nih.gov Subject: America/Chicago zone vs mktime w/tm_isdst!=-1 Here's an interesting problem. Usually when mktime() is called with tm_isdst set to 0 or 1, it will interpret the original time as being either in standard or daylight time according to tm_isdst, and update the resulting time_t value (and the struct tm) if the DST flag was wrong. This doesn't seem to happen with the America/Chicago zone. I've attached a simple program that passes three struct tm's to mktime, with three values of tm_isdst each. For most zones, the first and last times change depending on what value of tm_isdst is passed in. For America/Chicago, it looks like tm_isdst is ignored. Is it used correctly for the middle time (since it's in the fall-back range). Someone filed a FreeBSD PR against this back in June ( http://www.freebsd.org/cgi/query-pr.cgi?pr=53899 ), and I've verified the behaviour back to FreeBSD 4.0 (which had imported tzcode1999a). The classictzcode.tar.gz on elsie.nci.nih.gov looks at tm_isdst in all cases, so the change happened sometime between 1994 and 1999. I don't know if there are archives of tzcode sources, or I could pinpoint the exact release. It's not strictly a bug since POSIX basically says that any tm_isdst != -1 results in implementation-defined behaviour, but it's troublesome if the behaviour changes from zone to zone, and the current releases of Solaris, Tru64, AIX, and glibc(Linux) are consistent across timezones (they all adjust the incoming struct tm based on tm_isdst). And, a couple of POSIX/C99 links for the archives: http://www.opengroup.org/onlinepubs/007904975/functions/mktime.html http://std.dkuug.dk/JTC1/SC22/WG14/www/docs/dr_280.htm -- Dan Nelson dnelson(a)allantgroup.com

2 1

tzcode port to delphi
by Wayne Stanton Dec. 4, 2003

Dec. 4, 2003

Hi there, Does any know of a port of the tzcode to delphi or another windows specific compiler? thanks Wayne Stanton

1 0

FW: tzcode port to delphi
by Olson, Arthur David (NIH/NCI) Dec. 4, 2003

Dec. 4, 2003

Wayne Stanton is on the time zone mailing list, but at a different address than the one from which the message below originated. --ado -----Original Message----- From: Wayne Stanton [mailto:stantonw@optusnet.com.au] Sent: Wednesday, December 03, 2003 3:11 PM To: 'Tz (tz(a)elsie.nci.nih.gov)' Subject: tzcode port to delphi Hi there, Does any know of a port of the tzcode to delphi or another windows specific compiler? thanks Wayne Stanton

1 0

FW: Addition to http://www.twinsun.com/tz/tz-link.htm
by Olson, Arthur David (NIH/NCI) Dec. 4, 2003

Dec. 4, 2003

Steven R. Loomis has been added to the time zone mailing list after this message was received. --ado -----Original Message----- From: Steven R. Loomis [mailto:srl@jtcsv.com] Sent: Wednesday, December 03, 2003 8:32 PM To: tz(a)lecserver.nci.nih.gov Subject: Addition to http://www.twinsun.com/tz/tz-link.htm The International Components for Unicode library for C/C++ (ICU) uses tzdata in its historic time zone calculations. Our URL is http://oss.software.ibm.com/icu/ Would you consider adding a link to the page http://www.twinsun.com/tz/tz-link.htm ? Thank you and regards, Steven R. Loomis

1 0

Addition to http://www.twinsun.com/tz/tz-link.htm
by Steven R. Loomis Dec. 4, 2003

Dec. 4, 2003

The International Components for Unicode library for C/C++ (ICU) uses tzdata in its historic time zone calculations. Our URL is http://oss.software.ibm.com/icu/ Would you consider adding a link to the page http://www.twinsun.com/tz/tz-link.htm ? Thank you and regards, Steven R. Loomis

1 0

tzcode port to delphi
by Wayne Stanton Dec. 3, 2003

Dec. 3, 2003

Hi there, Does any know of a port of the tzcode to delphi or another windows specific compiler? thanks Wayne Stanton

1 0

RE: compile errors on timezone database
by Olson, Arthur David (NIH/NCI) Dec. 3, 2003

Dec. 3, 2003

Another possibility is to change the spelling of... 24:00 ...to... 23:59:60 ...which works with any version of zic issued 1988 or later. Let's hear it for leap seconds! --ado -----Original Message----- From: tz-request(a)lecserver.nci.nih.gov [mailto:tz-request@lecserver.nci.nih.gov] On Behalf Of Rodrigo Severo Sent: Wednesday, December 03, 2003 5:58 AM To: 'diane_kledzik(a)notes.ntrs.com' Cc: Tz (tz(a)elsie.nci.nih.gov) Subject: Re: compile errors on timezone database Olson, Arthur David (NIH/NCI) wrote: >Back in 1998 zic was tweaked to accept 24:00 in "AT" fields; my guess >is that the version of zic being used predates that change. (If the >vendor hasn't stripped things and you're on a POSIX system, you can do >a... > what /path/to/the/executable/zic >...to get a version number; anything under 7.94 lacks the tweak; >anything beyond 7.95 has the tweak.) > >Mindful of folks with old compilers, it may be best to change the >northamerica file to avoid use of 24:00, changing the "lastSat 24:00" >references to "lastSun 0:00". (And perhaps using zic should generate >warning messages if a 24:00 shows up and zic's -v option has been >used.) > > Because of the lastSat-might-be-the-last-day-of-the-month issue the Right Thing to be done is to update zic and use the correct zoneinfo definition. Rodrigo Severo -- ---------------------------------------------------- Rodrigo Severo Fábrica de Idéias Fone: +55(61)321 1357 Fax: +55(61)223 1712 SBS - Quadra 2 - Ed. Empire Center - Sala 1301 Brasília/DF - Brasil CEP: 70.070-904 ----------------------------------------------------

4 3

RE: compile errors on timezone database
by Olson, Arthur David (NIH/NCI) Dec. 3, 2003

Dec. 3, 2003

Back in 1998 zic was tweaked to accept 24:00 in "AT" fields; my guess is that the version of zic being used predates that change. (If the vendor hasn't stripped things and you're on a POSIX system, you can do a... what /path/to/the/executable/zic ...to get a version number; anything under 7.94 lacks the tweak; anything beyond 7.95 has the tweak.) Mindful of folks with old compilers, it may be best to change the northamerica file to avoid use of 24:00, changing the "lastSat 24:00" references to "lastSun 0:00". (And perhaps using zic should generate warning messages if a 24:00 shows up and zic's -v option has been used.) --ado -----Original Message----- From: Diane Kledzik [mailto:Diane_Kledzik@notes.ntrs.com] Sent: Tuesday, December 02, 2003 12:52 PM To: tz(a)lecserver.nci.nih.gov Cc: eggert(a)twinsun.com Subject: compile errors on timezone database As an fyi, I receive compile errors when I compile (using "zic") the time zone database downloaded in the tzdata2003d.tar file from your ftp://elsie.nci.nih.gov/pub/ site. The error messages read: "northamerica", line 954: invalid time of day "northamerica", line 955: invalid time of day "northamerica", line 978: invalid time of day "northamerica", line 979: invalid time of day Those lines in the northamerica file are below. Is it safe to assume I need to change the 24:00 references to 0:00 instead? Has anyone else run into this problem? Rule Mont 1927 1937 - Apr lastSat 24:00 1:00 D Rule Mont 1927 1937 - Sep lastSat 24:00 0 S Rule Toronto 1930 1937 - Apr lastSat 24:00 1:00 D Rule Toronto 1930 1937 - Sep lastSat 24:00 0 S Thanks for your help, Diane Kledzik

4 3

FW: compile errors on timezone database
by Olson, Arthur David (NIH/NCI) Dec. 2, 2003

Dec. 2, 2003

Diane Kledzik is not on the time zone mailing list; direct replies appropriately. --ado -----Original Message----- From: Diane Kledzik [mailto:Diane_Kledzik@notes.ntrs.com] Sent: Tuesday, December 02, 2003 12:52 PM To: tz(a)lecserver.nci.nih.gov Cc: eggert(a)twinsun.com Subject: compile errors on timezone database As an fyi, I receive compile errors when I compile (using "zic") the time zone database downloaded in the tzdata2003d.tar file from your ftp://elsie.nci.nih.gov/pub/ site. The error messages read: "northamerica", line 954: invalid time of day "northamerica", line 955: invalid time of day "northamerica", line 978: invalid time of day "northamerica", line 979: invalid time of day Those lines in the northamerica file are below. Is it safe to assume I need to change the 24:00 references to 0:00 instead? Has anyone else run into this problem? Rule Mont 1927 1937 - Apr lastSat 24:00 1:00 D Rule Mont 1927 1937 - Sep lastSat 24:00 0 S Rule Toronto 1930 1937 - Apr lastSat 24:00 1:00 D Rule Toronto 1930 1937 - Sep lastSat 24:00 0 S Thanks for your help, Diane Kledzik

2 1

compile errors on timezone database
by Diane Kledzik Dec. 2, 2003

Dec. 2, 2003

As an fyi, I receive compile errors when I compile (using "zic") the time zone database downloaded in the tzdata2003d.tar file from your ftp://elsie.nci.nih.gov/pub/ site. The error messages read: "northamerica", line 954: invalid time of day "northamerica", line 955: invalid time of day "northamerica", line 978: invalid time of day "northamerica", line 979: invalid time of day Those lines in the northamerica file are below. Is it safe to assume I need to change the 24:00 references to 0:00 instead? Has anyone else run into this problem? Rule Mont 1927 1937 - Apr lastSat 24:00 1:00 D Rule Mont 1927 1937 - Sep lastSat 24:00 0 S Rule Toronto 1930 1937 - Apr lastSat 24:00 1:00 D Rule Toronto 1930 1937 - Sep lastSat 24:00 0 S Thanks for your help, Diane Kledzik

1 0