Re: [Xenomai-help] Problem with gettimeofday

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Soboljew, Patrick wrote:
> Hello all,
> 
> I have a problem concering the system time in xenomai 2.4.9.1 kernel
> 2.6.30. The framework I use calls gettimeofday() to get the absolute
> system time which is then passed to pthread_cond_timedwait. The problem
> is that when I add for example 1ms wait time the pthread_cond_timedwait
> waits much longer. I've checked /proc/xenomai/sched and I can see that
> the timeout is far too large. So I wrote a small test program to isolate
> the problem. I compared the results (only the seconds which is enough to
> show the problem) and there is a huge difference.
> 
> On my system (Intel Core2, 1,6 GHz) the output of the test program shows
> the following output:
> Time1: 1260437136
> Time2: 1145908535
> 
> The curious thing is: I have a vmware image with a xenomai kernel (same
> version). The problem cannot be reproduced here. 
> 
> Anybody an idea?

You should be using clock_gettime(CLOCK_REALTIME). In case you insist on
using gettimeofday, see:

http://www.xenomai.org/index.php/Porting_POSIX_applications_to_Xenomai#Timing_services.

-- 
                                          Gilles