Rich Wales suggested that Iran's daylight-saving rules correspond to the Persian calendar and I found another expert source who agrees. This clarifies the daylight saving rules for Iran (and points out what appear to be minor errors in the IATA SSIM). Here's a patch embodying his suggestion, along with a better explanation of the Soviet week from 1929 through 1940 thanks to Chris Carrier, and some miscellaneous spelling fixes (including one fix to a message in `zic'). =================================================================== RCS file: RCS/zic.c,v retrieving revision 1996.14 retrieving revision 1996.14.1.1 diff -c -r1996.14 -r1996.14.1.1 *** zic.c 1996/12/16 14:42:02 1996.14 --- zic.c 1996/12/18 06:42:29 1996.14.1.1 *************** *** 1697,1703 **** (void) strcpy(startbuf, zp->z_format); eat(zp->z_filename, zp->z_linenum); if (*startbuf == '\0') ! error(_("can't determine time zone abbrevation to use just after until time")); else addtt(starttime, addtype(startoff, startbuf, startoff != zp->z_gmtoff, --- 1697,1703 ---- (void) strcpy(startbuf, zp->z_format); eat(zp->z_filename, zp->z_linenum); if (*startbuf == '\0') ! error(_("can't determine time zone abbreviation to use just after until time")); else addtt(starttime, addtype(startoff, startbuf, startoff != zp->z_gmtoff, =================================================================== RCS file: RCS/asia,v retrieving revision 1996.13 retrieving revision 1996.13.1.1 diff -c -r1996.13 -r1996.13.1.1 *** asia 1996/11/24 01:07:37 1996.13 --- asia 1996/12/18 06:42:29 1996.13.1.1 *************** *** 354,359 **** --- 354,379 ---- 9:00 - JAYT # Iran + # From Paul Eggert (1996-12-17), following up a suggestion by Rich Wales: + # Ahmad Alavi <URL:http://tehran.stanford.edu/Iran_Lib/Calendar/taghveem.txt> + # (1993-08-04) writes ``Daylight saving time in Iran starts from the first day + # of Farvardin and ends the first day of Mehr.'' This disagrees with the SSIM: + # + # DST start DST end + # year SSIM Alavi SSIM Alavi + # 1991 05-03!= 03-21 09-20!= 09-23 + # 1992 03-22!= 03-21 09-23 09-23 + # 1993 03-21 03-21 09-23 09-23 + # 1994 03-21 03-21 09-22!= 09-23 + # 1995 03-21 03-21 09-22!= 09-23 + # 1996 03-21!= 03-20 09-21!= 09-22 + # 1997 03-21 03-21 09-21!= 09-23 + # + # Go with Alavi starting with 1992. + # I used Ed Reingold's cal-persia in GNU Emacs 19.34 to compute Persian dates. + # The Persian calendar is based on the sun, and dates after around 2050 + # are approximate; stop after 2037 when 32-bit time_t's overflow. + # # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Iran 1978 1980 - Mar 21 0:00 1:00 S Rule Iran 1978 only - Oct 21 0:00 0 - *************** *** 361,371 **** Rule Iran 1980 only - Sep 23 0:00 0 - Rule Iran 1991 only - May 3 0:00s 1:00 S Rule Iran 1991 only - Sep 20 0:00s 0 - ! Rule Iran 1992 only - Mar 22 0:00 1:00 S ! Rule Iran 1992 1993 - Sep 23 0:00 0 - ! Rule Iran 1993 max - Mar 21 0:00 1:00 S ! Rule Iran 1994 1995 - Sep 22 0:00 0 - ! Rule Iran 1996 max - Sep 21 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tehran 3:25:44 - LMT 1916 3:25:44 - TMT 1946 # Tehran Mean Time --- 381,430 ---- Rule Iran 1980 only - Sep 23 0:00 0 - Rule Iran 1991 only - May 3 0:00s 1:00 S Rule Iran 1991 only - Sep 20 0:00s 0 - ! Rule Iran 1992 1995 - Mar 21 0:00 1:00 S ! Rule Iran 1992 1995 - Sep 23 0:00 0 - ! Rule Iran 1996 only - Mar 20 0:00 1:00 S ! Rule Iran 1996 only - Sep 22 0:00 0 - ! Rule Iran 1997 1999 - Mar 21 0:00 1:00 S ! Rule Iran 1997 1999 - Sep 23 0:00 0 - ! Rule Iran 2000 only - Mar 20 0:00 1:00 S ! Rule Iran 2000 only - Sep 22 0:00 0 - ! Rule Iran 2001 2003 - Mar 21 0:00 1:00 S ! Rule Iran 2001 2003 - Sep 23 0:00 0 - ! Rule Iran 2004 only - Mar 20 0:00 1:00 S ! Rule Iran 2004 only - Sep 22 0:00 0 - ! Rule Iran 2005 2007 - Mar 21 0:00 1:00 S ! Rule Iran 2005 2007 - Sep 23 0:00 0 - ! Rule Iran 2008 only - Mar 20 0:00 1:00 S ! Rule Iran 2008 only - Sep 22 0:00 0 - ! Rule Iran 2009 2011 - Mar 21 0:00 1:00 S ! Rule Iran 2009 2011 - Sep 23 0:00 0 - ! Rule Iran 2012 only - Mar 20 0:00 1:00 S ! Rule Iran 2012 only - Sep 22 0:00 0 - ! Rule Iran 2013 2015 - Mar 21 0:00 1:00 S ! Rule Iran 2013 2015 - Sep 23 0:00 0 - ! Rule Iran 2016 only - Mar 20 0:00 1:00 S ! Rule Iran 2016 only - Sep 22 0:00 0 - ! Rule Iran 2017 2019 - Mar 21 0:00 1:00 S ! Rule Iran 2017 2019 - Sep 23 0:00 0 - ! Rule Iran 2020 only - Mar 20 0:00 1:00 S ! Rule Iran 2020 only - Sep 22 0:00 0 - ! Rule Iran 2021 2023 - Mar 21 0:00 1:00 S ! Rule Iran 2021 2023 - Sep 23 0:00 0 - ! Rule Iran 2024 2025 - Mar 20 0:00 1:00 S ! Rule Iran 2024 2025 - Sep 22 0:00 0 - ! Rule Iran 2026 2027 - Mar 21 0:00 1:00 S ! Rule Iran 2026 2027 - Sep 23 0:00 0 - ! Rule Iran 2028 2029 - Mar 20 0:00 1:00 S ! Rule Iran 2028 2029 - Sep 22 0:00 0 - ! Rule Iran 2030 2031 - Mar 21 0:00 1:00 S ! Rule Iran 2030 2031 - Sep 23 0:00 0 - ! Rule Iran 2032 2033 - Mar 20 0:00 1:00 S ! Rule Iran 2032 2033 - Sep 22 0:00 0 - ! Rule Iran 2034 2035 - Mar 21 0:00 1:00 S ! Rule Iran 2034 2035 - Sep 23 0:00 0 - ! Rule Iran 2036 2037 - Mar 20 0:00 1:00 S ! Rule Iran 2036 2037 - Sep 22 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tehran 3:25:44 - LMT 1916 3:25:44 - TMT 1946 # Tehran Mean Time *************** *** 492,498 **** # # ftp://ftp.huji.ac.il/pub/misc/timezones/announcements/1996-1998.ps.gz # ! # Emptor Caveat: The dates for the years 1996-1998 were originally announced # on 1995-08-31, by the previous Minister of Interior. The new Minister # of Interior changed the dates on 1996-01-01, to take into account the # desires of certain portions of Israeli society (the next election is in the --- 551,557 ---- # # ftp://ftp.huji.ac.il/pub/misc/timezones/announcements/1996-1998.ps.gz # ! # Caveat emptor: The dates for the years 1996-1998 were originally announced # on 1995-08-31, by the previous Minister of Interior. The new Minister # of Interior changed the dates on 1996-01-01, to take into account the # desires of certain portions of Israeli society (the next election is in the =================================================================== RCS file: RCS/australasia,v retrieving revision 1996.13 retrieving revision 1996.13.1.2 diff -c -r1996.13 -r1996.13.1.2 *** australasia 1996/11/24 01:07:37 1996.13 --- australasia 1996/12/18 06:59:16 1996.13.1.2 *************** *** 48,62 **** # so use Lindeman. # # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S ! Rule QL 1989 1991 - Oct lastSun 2:00s 1:00 - ! Rule QL 1990 1992 - Mar Sun>=1 2:00s 0 - Rule Holiday 1989 1993 - Oct lastSun 2:00s 1:00 - Rule Holiday 1990 1994 - Mar Sun>=1 2:00s 0 - Zone Australia/Brisbane 10:12:08 - LMT 1895 10:00 - EST 1917 Jan 1 0:01 10:00 Aus EST 1971 Oct lastSun 2:00s 10:00 1:00 EST 1972 Feb lastSun 2:00s ! 10:00 QL EST Zone Australia/Lindeman 9:55:56 - LMT 1895 10:00 - EST 1917 Jan 1 0:01 10:00 Aus EST 1971 Oct lastSun 2:00s --- 48,62 ---- # so use Lindeman. # # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S ! Rule AQ 1989 1991 - Oct lastSun 2:00s 1:00 - ! Rule AQ 1990 1992 - Mar Sun>=1 2:00s 0 - Rule Holiday 1989 1993 - Oct lastSun 2:00s 1:00 - Rule Holiday 1990 1994 - Mar Sun>=1 2:00s 0 - Zone Australia/Brisbane 10:12:08 - LMT 1895 10:00 - EST 1917 Jan 1 0:01 10:00 Aus EST 1971 Oct lastSun 2:00s 10:00 1:00 EST 1972 Feb lastSun 2:00s ! 10:00 AQ EST Zone Australia/Lindeman 9:55:56 - LMT 1895 10:00 - EST 1917 Jan 1 0:01 10:00 Aus EST 1971 Oct lastSun 2:00s *************** *** 339,345 **** 9:00 - PWT # Palau Time # Palmyra ! # uninhabited since World War II; was probably like Pacific/Kiritmati # Papua New Guinea # Zone NAME GMTOFF RULES FORMAT [UNTIL] --- 339,345 ---- 9:00 - PWT # Palau Time # Palmyra ! # uninhabited since World War II; was probably like Pacific/Kiritimati # Papua New Guinea # Zone NAME GMTOFF RULES FORMAT [UNTIL] =================================================================== RCS file: RCS/europe,v retrieving revision 1996.13 retrieving revision 1996.13.1.1 diff -c -r1996.13 -r1996.13.1.1 *** europe 1996/11/24 01:07:37 1996.13 --- europe 1996/12/18 06:42:29 1996.13.1.1 *************** *** 78,84 **** # of the text said: # # `An old stone obelisk marking a forgotten terrestrial meridian stands ! # beside the river at Kew. In the 18th century, before time and longditude # was standardised by the Royal Observatory in Greenwich, scholars observed # this stone and the movement of stars from Kew Observatory nearby. They # made their calculations and set the time for the Horse Guards and Parliament, --- 78,84 ---- # of the text said: # # `An old stone obelisk marking a forgotten terrestrial meridian stands ! # beside the river at Kew. In the 18th century, before time and longitude # was standardised by the Royal Observatory in Greenwich, scholars observed # this stone and the movement of stars from Kew Observatory nearby. They # made their calculations and set the time for the Horse Guards and Parliament, *************** *** 86,92 **** # along the towpath within a few yards of it.' # # I have a one inch to one mile map of London and my estimate of the stone's ! # position is 51 deg. 28' 30" N, 0 deg. 18' 45" W. The longditude should # be within about +-2". The Ordnance Survey grid reference is TQ172761. # # [This yields GMTOFF = -0:01:15 for London LMT in the 18th century.] --- 86,92 ---- # along the towpath within a few yards of it.' # # I have a one inch to one mile map of London and my estimate of the stone's ! # position is 51 deg. 28' 30" N, 0 deg. 18' 45" W. The longitude should # be within about +-2". The Ordnance Survey grid reference is TQ172761. # # [This yields GMTOFF = -0:01:15 for London LMT in the 18th century.] *************** *** 167,173 **** # It ends at 02:00 GMT on the morning of the day after the fourth Saturday # in October. (All the redundant `morning of the day ...' is in the Act.) # This is only of passing interest now as it will always be overridden by ! # an Order in Council (a Statutary Instrument, the SI thing mentioned above) # to specify the EC specified dates. # From Peter Ilieve <peter@memex.co.uk> (1993-10-18): --- 167,173 ---- # It ends at 02:00 GMT on the morning of the day after the fourth Saturday # in October. (All the redundant `morning of the day ...' is in the Act.) # This is only of passing interest now as it will always be overridden by ! # an Order in Council (a Statutory Instrument, the SI thing mentioned above) # to specify the EC specified dates. # From Peter Ilieve <peter@memex.co.uk> (1993-10-18): *************** *** 327,333 **** # so that part of the 1922 Act will still apply. # # - The Defence (Summer Time) Regulations, 1939, SR&O 1939 No. 1379 ! # [SR&O == Statutary Regulation and Order] # # These were made under the Emergency Powers (Defence) Act, 1939. # It changes the end date to be the day after the third Saturday in November. --- 327,333 ---- # so that part of the 1922 Act will still apply. # # - The Defence (Summer Time) Regulations, 1939, SR&O 1939 No. 1379 ! # [SR&O == Statutory Regulation and Order] # # These were made under the Emergency Powers (Defence) Act, 1939. # It changes the end date to be the day after the third Saturday in November. *************** *** 403,409 **** # harmonise with the EC since 1981. The major change is that the time changes # to 01:00 GMT.) # ! # - The Summer Time Order, 1992, SI 1992/1729 [SI == Statutary Instrument] # # This specifies dates of: # Start End --- 403,409 ---- # harmonise with the EC since 1981. The major change is that the time changes # to 01:00 GMT.) # ! # - The Summer Time Order, 1992, SI 1992/1729 [SI == Statutory Instrument] # # This specifies dates of: # Start End *************** *** 1298,1304 **** 1:00 Greece CE%sT 1944 Apr 4 2:00 Greece EE%sT 1981 # Shanks says they switched to C-Eur in 1981; ! # go with EU intead, since Greece joined it on Jan 1. 2:00 EU EE%sT # Hungary --- 1298,1304 ---- 1:00 Greece CE%sT 1944 Apr 4 2:00 Greece EE%sT 1981 # Shanks says they switched to C-Eur in 1981; ! # go with EU instead, since Greece joined it on Jan 1. 2:00 EU EE%sT # Hungary *************** *** 1819,1827 **** 2:00 E-Eur EE%sT # Russia ! # From Shanks (1991): ! # In 1929 the Soviet Union instituted a 5 day week; in 1932 it instituted ! # a 6 day week; on 1940-06-27 it returned to the Gregorian week. # # From Paul Eggert <eggert@twinsun.com> (1996-11-22): # Except for Moscow after 1919-07-01, I invented the time zone abbreviations, --- 1819,1833 ---- 2:00 E-Eur EE%sT # Russia ! ! # From Chris Carrier <72157.3334@CompuServe.COM> (1996-12-02): ! # On 1929-10-01 the Soviet Union instituted an ``Eternal Calendar'' ! # with 30-day months plus 5 holidays, with a 5-day week. ! # On 1931-12-01 it changed to a 6-day week; in 1934 it reverted to the ! # Gregorian calendar while retaining the 6-day week; on 1940-06-27 it ! # reverted to the 7-day week. With the 6-day week the usual days ! # off were the 6th, 12th, 18th, 24th and 30th of the month. ! # (Source: Evitiar Zerubavel, _The Seven Day Circle_) # # From Paul Eggert <eggert@twinsun.com> (1996-11-22): # Except for Moscow after 1919-07-01, I invented the time zone abbreviations, *************** *** 1882,1888 **** # as far as I remember it was done exactly during winter->summer switching # so we (Novosibirsk) simply did not switch. Zone Asia/Novosibirsk 5:31:40 - LMT 1924 May 2 ! 6:00 - NOVT 1957 Mar # Novosibirsk TIme 7:00 Russia NOV%sT 1991 Mar 31 2:00s 6:00 1:00 NOVST 1991 Sep 29 2:00s 6:00 - NOVT 1992 Jan 19 2:00s --- 1888,1894 ---- # as far as I remember it was done exactly during winter->summer switching # so we (Novosibirsk) simply did not switch. Zone Asia/Novosibirsk 5:31:40 - LMT 1924 May 2 ! 6:00 - NOVT 1957 Mar # Novosibirsk Time 7:00 Russia NOV%sT 1991 Mar 31 2:00s 6:00 1:00 NOVST 1991 Sep 29 2:00s 6:00 - NOVT 1992 Jan 19 2:00s *************** *** 2134,2140 **** # Ukraine # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Ukraine 1917 only - Jul 1 23:00 1:00 UST # Ukrainian Summer Time ! Rule Ukraine 1917 only - Dec 28 0:00 0 KMT # Kiev Mean TIme Rule Ukraine 1918 only - May 31 22:00 2:00 UDST # Ukrainian Double Summer Time Rule Ukraine 1918 only - Sep 17 0:00 1:00 UST Rule Ukraine 1919 only - May 31 23:00 2:00 UDST --- 2140,2146 ---- # Ukraine # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Ukraine 1917 only - Jul 1 23:00 1:00 UST # Ukrainian Summer Time ! Rule Ukraine 1917 only - Dec 28 0:00 0 KMT # Kiev Mean Time Rule Ukraine 1918 only - May 31 22:00 2:00 UDST # Ukrainian Double Summer Time Rule Ukraine 1918 only - Sep 17 0:00 1:00 UST Rule Ukraine 1919 only - May 31 23:00 2:00 UDST =================================================================== RCS file: RCS/northamerica,v retrieving revision 1996.13 retrieving revision 1996.13.1.1 diff -c -r1996.13 -r1996.13.1.1 *** northamerica 1996/11/24 01:07:37 1996.13 --- northamerica 1996/12/18 06:42:29 1996.13.1.1 *************** *** 920,928 **** # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND # MEXICO BAJA CAL N N. PACIFIC COAST (STATES # MEXICO BAJA CAL N OF SINALOA AND SONORA) ! # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLAL APR 3 # MEXICO BAJA CAL N - OCT 29 ! # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLAL APR 3 # MEXICO BAJA CAL N - 0CT 29 # MEXICO 6 H BEHIND UTC STATES OF DURANGO, # MEXICO COAHUILA, NUEVO LEON, --- 920,928 ---- # MEXICO BAJA CAL N 7 H BEHIND UTC BAJA CALIFORNIA SUR AND # MEXICO BAJA CAL N N. PACIFIC COAST (STATES # MEXICO BAJA CAL N OF SINALOA AND SONORA) ! # MEXICO BAJA CAL N 8 H BEHIND UTC ABOVE 28TH PARALLEL APR 3 # MEXICO BAJA CAL N - OCT 29 ! # MEXICO BAJA CAL N 7 H BEHIND UTC ABOVE 28TH PARALLEL APR 3 # MEXICO BAJA CAL N - 0CT 29 # MEXICO 6 H BEHIND UTC STATES OF DURANGO, # MEXICO COAHUILA, NUEVO LEON, =================================================================== RCS file: RCS/southamerica,v retrieving revision 1996.13 retrieving revision 1996.13.1.1 diff -c -r1996.13 -r1996.13.1.1 *** southamerica 1996/11/24 01:07:37 1996.13 --- southamerica 1996/12/18 06:42:29 1996.13.1.1 *************** *** 61,67 **** # ARGENTINA 3 H BEHIND UTC # From Hernan G. Otero <hernan@isoft.com.ar> (1995-06-26): ! # I am sending modifications to the Argentinian time zone table... # AR was chosen because they are the ISO letters that represent Argentina. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S --- 61,67 ---- # ARGENTINA 3 H BEHIND UTC # From Hernan G. Otero <hernan@isoft.com.ar> (1995-06-26): ! # I am sending modifications to the Argentine time zone table... # AR was chosen because they are the ISO letters that represent Argentina. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S *************** *** 99,105 **** # These corrections were contributed by InterSoft Argentina S.A., # obtaining the data from the: # Talleres de Hidrografia Naval Argentina ! # (Argentinian Naval Hydrography Institute) # # Shanks gives 1989 Mar 16 and stops after 1990 Mar 4; go with Otero. Rule Arg 1989 1993 - Mar Sun>=1 0:00 0 - --- 99,105 ---- # These corrections were contributed by InterSoft Argentina S.A., # obtaining the data from the: # Talleres de Hidrografia Naval Argentina ! # (Argentine Naval Hydrography Institute) # # Shanks gives 1989 Mar 16 and stops after 1990 Mar 4; go with Otero. Rule Arg 1989 1993 - Mar Sun>=1 0:00 0 -