Re: RFC 48 (v2) Replace localtime() and gmtime() with da

[Tim Jenness]

On 11 Aug 2000, Russ Allbery wrote:

> Nathan Wiger <[EMAIL PROTECTED]> writes:
> 
> > The problem is, many people on this list claimed that GMT != UTC,
> 
> Correct.
> 
> > and that machine time is only in GMT, making UTC dicey to derive.
> 
> Nope.  Other way around.  Machine time is only UTC; GMT has fractional
> skew instead of leap seconds, making it rather incompatible with
> computers.
> 

See 

  http://www.jach.hawaii.edu/JACpublic/stardocs/sun67.htx/node217.html

for a description of the different timescales as implemented by the SLALIB
astrometry library (used by telescopes around the world). It tells you
the difference between UT, UTC, GMT and others.

-- 
Tim Jenness
JCMT software engineer/Support scientist
http://www.jach.hawaii.edu/~timj