RE: Measure time

Hi,

ftime() will return milliseconds, but it's considered an obsolete function.
You could use gettimeofday() (as Richard Johnson suggested) to get
microseconds and divide them to get milliseconds, although I don't know how
time critical your routines are.

If you're still looking for nanoseconds, I'm told you can use
clock_gettime() but it's still quite unavailable (I've never seen it myself,
yet).. however even if it was available you possibly wouldn't get a very
high resolution from it with current systems..

 - Simon

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of Serguei I. Ivantsov
> Sent: Thursday, 9 May 2002 01:47
> To: Der Herr Hofrat
> Cc: [email protected]; [email protected]
> Subject: Re: Measure time
>
>
> Is there any function like GetTickCount() in M$ Win32 that
> retrieves time in
> milliseconds?
>
> --
>  Regards,
>   Serguei I. Ivantsov
>
> ----- Original Message -----
> From: "Der Herr Hofrat" <[email protected]>
> To: "Serguei I. Ivantsov" <[email protected]>
> Cc: <[email protected]>; <[email protected]>
> Sent: Wednesday, May 08, 2002 3:00 PM
> Subject: Re: Measure time
>
>
> > > Hello!
> > >
> > > Is there any function for high precision time measuring.
> > > time() returns only in second. I need nanoseconds.
> > >
> > you can directly read the TSC but that will not realy give you
> nanoseconds
> > resolution as the actual read access even on a PIII/1GHz is
> going to take
> > up to a few 100 nanoseconds, and depending on what you want to time
> > stamp the overall jitter of that code can easaly be in the
> > range of a microsecond.
> >
> > There are some hard-realtime patches to the Linux kernel that will
> > allow time precission of aprox. 1us (the TSC has a precission of 32ns)
> > but I don't think you can get below that without dedicated hardware.
> >
> > for RTLinux check at ftp://ftp.rtlinux.org/pub/rtlinux/
> >
> > hofrat
>
> -
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