On Die, 2008-09-02 at 21:16 +0200, John Hay wrote:
> On Tue, Sep 02, 2008 at 07:24:01PM +0200, Bernd Petrovitsch wrote:
> ...
> > Not really:
> > gettimeofday(2) and time(2) return the current date+time (read: that
> > what the device thinks it is) or some representation of it.
> > The problem with that is that it is not continuous because
> > ntp/ntpdate/rdate/the admin/daylight-saving-time/... may change speed
> > and value at any time (and I purposely ignore leap seconds).
> > These values are great for syslog and other time values which refer to
> > the rest of the planet.
> > 
> > For timeouts in select/poll/sleep/timers in general one wants a steady
> > clock without jumps. And times(2) is the only portable sys-call I know
> > of.
> 
> What about clock_gettime(2)? According to the FreeBSD man page it is

I assume you mean the CLOCK_MONOTONIC "version".
Why not?

> part of IEEE Std 1003.1b-1993 (``POSIX.1'').

Sorry;-), but times(2) is also in SuSv3:
http://www.opengroup.org/onlinepubs/009695399/functions/times.html

Sven-Ola (or anyone else;-), do we want/have librt.(a|so) on openwrt and
other smallish hardware/systems?
At least on my Fedora-9, I need "-lrt" to be able to link it.
Or did I overlook something?

> > BTW do we have requirements on precision?
> 
> clock_gettime(2) give down to nanosecond level, which should be ok for
> a while I guess. :-)

IMHO for sure. But it is needed?

	Bernd
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