West of Long 0 : Pos or Neg?

seismo!nbires!vianet!devine seismo!nbires!vianet!devine
Tue Feb 10 21:45:11 UTC 1987

Mark Horton says:
> In my implementation, I added two fields to struct tm, for the hours and
> minutes in the time zone which resolved the ambiguity.
> (both are negative for us in the USA)

kre says:
> Secondly, I'm not sure why you chose to have West of Greenwich being
> negative.  All previous uses of timezone offsets in Unix have been
> the other way - West of Greenwich positive.  

  I favor the ISO rule.  Every international organization (but, I'm
sure there are exceptions) has adopted the East of Longitude 0 is
positive; west is negative.  If we are proposing POSIX as an
international standard, we should accept the international rules.

  The UNIX convention is unfortunately wrong. It was one of those 50/50
chances (like determining whether the flow of electicity is positive
or negative) that was incorrectly chosen.  Dems da breaks.

Bob Devine

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