1 # <pre>
   2 # This file is in the public domain, so clarified as of
   3 # 2009-05-17 by Arthur David Olson.
   4 
   5 # Old rules, should the need arise.
   6 # No attempt is made to handle Newfoundland, since it cannot be expressed
   7 # using the System V "TZ" scheme (half-hour offset), or anything outside
   8 # North America (no support for non-standard DST start/end dates), nor
   9 # the changes in the DST rules in the US after 1976 (which occurred after
  10 # the old rules were written).
  11 #
  12 # If you need the old rules, uncomment ## lines.
  13 # Compile this *without* leap second correction for true conformance.
  14 
  15 # Rule  NAME    FROM    TO      TYPE    IN      ON      AT      SAVE    LETTER/S
  16 Rule    SystemV min     1973    -       Apr     lastSun 2:00    1:00    D
  17 Rule    SystemV min     1973    -       Oct     lastSun 2:00    0       S
  18 Rule    SystemV 1974    only    -       Jan     6       2:00    1:00    D
  19 Rule    SystemV 1974    only    -       Nov     lastSun 2:00    0       S
  20 Rule    SystemV 1975    only    -       Feb     23      2:00    1:00    D
  21 Rule    SystemV 1975    only    -       Oct     lastSun 2:00    0       S
  22 Rule    SystemV 1976    max     -       Apr     lastSun 2:00    1:00    D
  23 Rule    SystemV 1976    max     -       Oct     lastSun 2:00    0       S
  24 
  25 # Zone  NAME            GMTOFF  RULES/SAVE      FORMAT  [UNTIL]
  26 ## Zone SystemV/AST4ADT -4:00   SystemV         A%sT
  27 ## Zone SystemV/EST5EDT -5:00   SystemV         E%sT
  28 ## Zone SystemV/CST6CDT -6:00   SystemV         C%sT
  29 ## Zone SystemV/MST7MDT -7:00   SystemV         M%sT
  30 ## Zone SystemV/PST8PDT -8:00   SystemV         P%sT
  31 ## Zone SystemV/YST9YDT -9:00   SystemV         Y%sT
  32 ## Zone SystemV/AST4    -4:00   -               AST
  33 ## Zone SystemV/EST5    -5:00   -               EST
  34 ## Zone SystemV/CST6    -6:00   -               CST
  35 ## Zone SystemV/MST7    -7:00   -               MST
  36 ## Zone SystemV/PST8    -8:00   -               PST
  37 ## Zone SystemV/YST9    -9:00   -               YST
  38 ## Zone SystemV/HST10   -10:00  -               HST