[tz] Buggy %z behaviour in strftime

[Russ Allbery]

Paul Gilmartin via tz <tz at iana.org> writes:

> It may be worse.  I read somewhere (citation needed) that in SMTP Date:
> headers a signed value indicates a geographic longitude; unsigned 0000
> merely UTC with location unspecified.

RFC 2822 section 3.3:

   The form "+0000" SHOULD be used to indicate a time zone at Universal
   Time.  Though "-0000" also indicates Universal Time, it is used to
   indicate that the time was generated on a system that may be in a local
   time zone other than Universal Time and therefore indicates that the
   date-time contains no information about the local time zone.

-- 
Russ Allbery (eagle at eyrie.org)             <https://www.eyrie.org/~eagle/>