> - gettimeofday() never returns the same value twice (documented BSD
> behaviour)
Ouch... gettimeofday(2) only presently has usec resolution. I suspect
we can make this report the same value twice on really high end boxes
(667MHz Alpha maybe, 400Mhz Sparcs?), if not now, in a year or so.
Even a P.ii 600 or so can probably manage it.
Sure... this is fixable and not hard to fix, but it requires breaking
binary compatibility.
The attached code on a PPro 200 gives me results of 2 usecs, using a
P.II 300 and SYSENTER semantics, you can probably get this to less
that 1usec.
> I don't know of a pretty way. What I'd like, as I said, is a
> defined kludge, so that there is a defined mapping between struct
> timeval and struct timespec and UTC in the vicinity of a leap
> second.
I'm not sure about a sane kludge for mapping to/from the semantics we
already have, but how about we just declare the existing API buggy
under some (rare circumstances) and create a new one with flags to
show whether or not a leap second is currently under way, much the
same as is done for daylight savings time with time zones. (You can
have two 2:30ams, only one of which tough is DST, the other is
non-DST).
-Chris
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