Re: [LEAPSECS] Mechanism to provide tai-utc.dat locally

From: Poul-Henning Kamp <>
Date: Wed, 27 Dec 2006 14:29:00 +0000

In message <>, Zefram writes:
>Ashley Yakeley wrote:

>>In the Haskell time library, I represent UTC time by what seemed to
>>me the simplest possible correct type. This is a record containing an
>>integer to represent day number (as MJD), and a fixed-point decimal
>>(picosecond resolution) to represent seconds since midnight. The
>>allowed range for this is 0 to 86400.999999999999.
>That's a pretty good format.

That's a pretty bad format. Computers are binary and having
pseudo-decimal fields like tv_usec in timeval, tv_nsec in timespec
and picoseconds in Haskell is both inefficient and stupid.

The fractional part should be a binary field, so that the width
can be adjusted to whatever precision and wordsize is relevant.

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk_at_FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
Received on Wed Dec 27 2006 - 06:39:26 PST

This archive was generated by hypermail 2.3.0 : Sat Sep 04 2010 - 09:44:55 PDT