Hi,

For those who care the leap second table is at ftp://maia.usno.navy.mil/ser7/tai-utc.dat 
and the contents are:

 1961 JAN  1 =JD 2437300.5  TAI-UTC=   1.4228180 S + (MJD - 37300.) X 0.001296 S
 1961 AUG  1 =JD 2437512.5  TAI-UTC=   1.3728180 S + (MJD - 37300.) X 0.001296 S
 1962 JAN  1 =JD 2437665.5  TAI-UTC=   1.8458580 S + (MJD - 37665.) X 0.0011232S
 1963 NOV  1 =JD 2438334.5  TAI-UTC=   1.9458580 S + (MJD - 37665.) X 0.0011232S
 1964 JAN  1 =JD 2438395.5  TAI-UTC=   3.2401300 S + (MJD - 38761.) X 0.001296 S
 1964 APR  1 =JD 2438486.5  TAI-UTC=   3.3401300 S + (MJD - 38761.) X 0.001296 S
 1964 SEP  1 =JD 2438639.5  TAI-UTC=   3.4401300 S + (MJD - 38761.) X 0.001296 S
 1965 JAN  1 =JD 2438761.5  TAI-UTC=   3.5401300 S + (MJD - 38761.) X 0.001296 S
 1965 MAR  1 =JD 2438820.5  TAI-UTC=   3.6401300 S + (MJD - 38761.) X 0.001296 S
 1965 JUL  1 =JD 2438942.5  TAI-UTC=   3.7401300 S + (MJD - 38761.) X 0.001296 S
 1965 SEP  1 =JD 2439004.5  TAI-UTC=   3.8401300 S + (MJD - 38761.) X 0.001296 S
 1966 JAN  1 =JD 2439126.5  TAI-UTC=   4.3131700 S + (MJD - 39126.) X 0.002592 S
 1968 FEB  1 =JD 2439887.5  TAI-UTC=   4.2131700 S + (MJD - 39126.) X 0.002592 S
 1972 JAN  1 =JD 2441317.5  TAI-UTC=  10.0       S + (MJD - 41317.) X 0.0      S
 1972 JUL  1 =JD 2441499.5  TAI-UTC=  11.0       S + (MJD - 41317.) X 0.0      S
 1973 JAN  1 =JD 2441683.5  TAI-UTC=  12.0       S + (MJD - 41317.) X 0.0      S
 1974 JAN  1 =JD 2442048.5  TAI-UTC=  13.0       S + (MJD - 41317.) X 0.0      S
 1975 JAN  1 =JD 2442413.5  TAI-UTC=  14.0       S + (MJD - 41317.) X 0.0      S
 1976 JAN  1 =JD 2442778.5  TAI-UTC=  15.0       S + (MJD - 41317.) X 0.0      S
 1977 JAN  1 =JD 2443144.5  TAI-UTC=  16.0       S + (MJD - 41317.) X 0.0      S
 1978 JAN  1 =JD 2443509.5  TAI-UTC=  17.0       S + (MJD - 41317.) X 0.0      S
 1979 JAN  1 =JD 2443874.5  TAI-UTC=  18.0       S + (MJD - 41317.) X 0.0      S
 1980 JAN  1 =JD 2444239.5  TAI-UTC=  19.0       S + (MJD - 41317.) X 0.0      S
 1981 JUL  1 =JD 2444786.5  TAI-UTC=  20.0       S + (MJD - 41317.) X 0.0      S
 1982 JUL  1 =JD 2445151.5  TAI-UTC=  21.0       S + (MJD - 41317.) X 0.0      S
 1983 JUL  1 =JD 2445516.5  TAI-UTC=  22.0       S + (MJD - 41317.) X 0.0      S
 1985 JUL  1 =JD 2446247.5  TAI-UTC=  23.0       S + (MJD - 41317.) X 0.0      S
 1988 JAN  1 =JD 2447161.5  TAI-UTC=  24.0       S + (MJD - 41317.) X 0.0      S
 1990 JAN  1 =JD 2447892.5  TAI-UTC=  25.0       S + (MJD - 41317.) X 0.0      S
 1991 JAN  1 =JD 2448257.5  TAI-UTC=  26.0       S + (MJD - 41317.) X 0.0      S
 1992 JUL  1 =JD 2448804.5  TAI-UTC=  27.0       S + (MJD - 41317.) X 0.0      S
 1993 JUL  1 =JD 2449169.5  TAI-UTC=  28.0       S + (MJD - 41317.) X 0.0      S
 1994 JUL  1 =JD 2449534.5  TAI-UTC=  29.0       S + (MJD - 41317.) X 0.0      S
 1996 JAN  1 =JD 2450083.5  TAI-UTC=  30.0       S + (MJD - 41317.) X 0.0      S
 1997 JUL  1 =JD 2450630.5  TAI-UTC=  31.0       S + (MJD - 41317.) X 0.0      S
 1999 JAN  1 =JD 2451179.5  TAI-UTC=  32.0       S + (MJD - 41317.) X 0.0      S


Remeber that julian days start at noon (hey, it makes sense if you are a
European astronomer) so JD 2451179.5 is midnight.  

cheers

bruce

On Sun, Sep 26, 2004 at 09:50:49PM -0400, David T. Lewis wrote:
> On Sun, Sep 26, 2004 at 03:58:43PM -0700, Tim Rowledge wrote:
> > "David T. Lewis" <lewis at mail.msen.com> wrote:
> > 
> > [snip]
> > > That's exactly what Lex is suggesting.
> > 
> > That might be what he meant but it isn't what he wrote... I quote...
> > >> . The time, probably as approximately[1] the number of seconds since
> > > > some epoch.
> 
> Tim,
> 
> Obviously you have been lulled into a false sense of security by the
> media.  The world is a wobbly place, full of uncertainty and all manner
> of imprecision.
> 
> Having paid quite close attention to these matters, I count no fewer
> than 22 leap seconds that have occurred since Jan 1, 1970 UTC.  Some
> of these cosmic recalibrations may have entirely escaped the notice
> of the less attentive among us, accounting for a general uncertainty
> as to where any of us really stands on the cosmic timeline. Small wonder
> if Lex may have felt a bit off center with regard to time primitives; it
> happens to all of us with advancing age. You really aught to be more
> sensitive about these things.
> 
> > Whereas I meant filling in an array of                                    
> >   int tm_sec;
> >   int tm_min;
> >   int tm_hour;
> >   int tm_mday;
> >   int tm_mon;
> >   int tm_year;
> >   int tm_wday;
> >   int tm_yday;
> >   int tm_isdst;
> 
> Well then, that's a horse of a different color. It's easy to be precise
> if one squints one's eyes and focuses only on the present.
>  ;-)
> 
> > Or whatever is suitable to the typical call. The above is RISC OS's
> > gmtime() equivalent. I'd need to find the DST offset as well I guess.
> 
> gmtime() has precision to the nearest second. Does RISC OS provide a
> gettimeofday() function? This is a BSD function that answers time to
> millisecond precision, and also provides the time zone offset and a
> flag denoting daylight savings time. If this or something like it is
> available on RISC OS, then it should be possible to implement Lex's
> suggestion on all the major Squeak platforms.
> 
> Dave
> 
> 

-- 
edoneel at sdf.lonestar.org
SDF Public Access UNIX System - http://sdf.lonestar.org