[comp.mail.headers] Interpretation of local time offset

MJL%DGAIPP1S.BITNET@MITVMA.MIT.EDU (Martin Lottermoser) (01/21/88)

In the date field of a message, RFC822 defines a <zone>. This can take
the form of +hhmm or -hhmm indicating "the amount of offset from UT"
(UTC is meant, I suppose). Unfortunately, I do not have access to the
ANSI standard X3.51-1975 quoted in RFC822, therefore I cannot determine
the meaning directly.

However, RFC822 specifies offsets for the American time zones and the
military ones. But again, unfortunately, these specifications disagree:

  (a) Consider the American time zones. RFC822 says, e.g.: EST = -5.
      Now, UTC can be obtained from EST by adding 5 hours. Therefore
      the interpretation should be:

         If an offset is given in a <date-time>, it specifies the amount
         one has to add to the given time to obtain UTC.

  (b) Now for the military time zones. RFC822 says, e.g.: "A:-1".
      But A is Central European Time, hence:

         To obtain UTC from a <date-time> with offset, one has to
         subtract the offset from the given time.

What is the correct interpretation?
                                             Martin