On 4/21/2017 11:35 AM, Phillip Hallam-Baker wrote:
On Fri, Apr 21, 2017 at 1:57 PM, Joe Touch <touch(_at_)isi(_dot_)edu
<mailto:touch(_at_)isi(_dot_)edu>> wrote:
On 4/21/2017 10:26 AM, Nico Williams wrote:
> "Internet time" (that which we use in [new] Internet protocols)
should
> just be TAI. And every existing Internet protocol should be
updated to
> indicate which time is used in practice, UTC or TAI, regardless
of what
> was originally specified.
I would be very glad of we defined Internet Time as TAI, but also
expect
all protocols to understand both TAI and UTC if possible.
Joe
To answer the issues raised:
1) POSIX already has this pretty much covered
http://pubs.opengroup.org/onlinepubs/009695399/functions/clock_getres.html;
int clock_gettime(clockid_t /clock_id/, struct timespec */tp/);
So all that is required is to define clock identifiers for:
TAI (The total number of seconds elapsed since the start of the epoch)
UTC (The TAI value adjusted for UTC leap seconds, i.e. number of non
leap second seconds since the start of the epoch)
If these aren't already included, I'm surprised (at least UTC).
PIT (The TAI value adjusted for PIT leap seconds)
We don't need PIT.
POSIX already defines constants
for CLOCK_PROCESS_CPUTIME_ID, CLOCK_REALTIME
All that is needed is to define the additional ones.
2) No I did not move the goalposts. My original proposal was to solve
the needless chaos caused be the idiotic notion of changing the
definition of time at six months notice. The stupidity of that notion
should be apparent to all.
There is no getting around the fact that the rest of the planet accepts
leap seconds. If that's not something you want to track, then use TAI
and be off-sync with the rest of the world when they use UTC.
PIT does nothing helpful except add yet another level of indirection and
confusion here.
3) Screw the astronomers. Pluto is to a planet.
IMO, this issue is sufficently driven by "rough consensus and running
code" of the entire planet right now - where all governments already use
UTC.
Joe