Harlan,
The NTP get_systime() routine calls one of three library routines,
clock_gettime(), getimeofday() and getclock(), depending on
autoconfigure. At least the first two and probably the last are kernel
system calls and don't depend on other routines. The clock_gettime() and
getclock() return nanoseconds in a timespec structure; the
gettimeofday() returns microseconds in a timeval structure. As these are
system calls, no matter what library they are in, they would operate the
same way. I have no documentation on getclock(), either in Solaris or
FreeBSD.
The fuzz is used only with gettimeofday() and yields about 12 bits of
the 32-bit fraction field. As there are about four NTP ticks in a
nanosecond, it is not productive to roll the random number generator to
yield only two bits.
Dave
Harlan Stenn wrote:
Dave,
I see to points Damion has raised where I do not see your response.
The first is that there exist several libraries where the C library provides
the nano calls but implements them using the (older) microsecond
calls. Therefore there is no data available below the microsecond and our
code is not handling this case.
The second point was related to this one, but it escapes me at the moment.
Damion, what does clock_getres() return on these systems?
I need to finish packing for a trip - more later.
H
--
In article <[EMAIL PROTECTED]>, "David L. Mills" <[EMAIL PROTECTED]> writes:
David> Damion, The ONLY function of the random fuzz is to fill the timestamp
David> bits below the microsecond, and this ONLY with the kernel syscall
David> that returns time in microseconds. Do NOT interpret the agenda in any
David> other way.
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