Re: nanosecond timestamp

[rick jones <rick.jones2 () hp com>]

> Perhaps, the man page says:
>
>      The gethrtime() function returns the current high-resolution
>      real time. Time is expressed as nanoseconds since some arbi-
>      trary time in the past; it is not correlated in any  way  to
>      the  time  of  day,  and thus is not subject to resetting or
>      drifting by way of adjtime(2) or settimeofday(3C).  The  hi-
>      res  timer  is  ideally  suited  to  performance measurement
>      tasks, where cheap, accurate interval timing is required.
>
> So something like "getimeofday(&foo, NULL); foohr = gethrtime()"
> would approximately equate foohr with foo, such that you could
> use the change in gethrtime() values returned to calculate the
> current time with more accuracy than just gettimeofday() ?

well, more digits at least :) but since gethrtim() isn't adjusted, it 
can drift as the computer would and so over time will diverge from time 
via gettimeofday()

now if a capture is reasonably short that is probably a dont care but 
over an hour or a day or so... just depends on how much the system 
drifts

rick

> Darren
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