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Subject: struct bintime
From: Jeremie Le Hen <jlh@FreeBSD.org>
To: freebsd-hackers@FreeBSD.org
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Hi,

I need to get microseconds from a struct bintime.  I found
bintime2timeval() in sys/time.h which more or less does this, but I
don't understand how the computation works.

Can someone explain it to me please?

static __inline void
bintime2timeval(const struct bintime *_bt, struct timeval *_tv)
{

        _tv->tv_sec = _bt->sec;
        _tv->tv_usec = ((uint64_t)1000000 * (uint32_t)(_bt->frac >> 32)) >> 32;
}

Thanks!
-- 
Jeremie Le Hen
jlh@FreeBSD.org