[alsa-devel] alsa timestamps

Heikki Lindholm holindho at cs.helsinki.fi
Mon Nov 19 13:54:16 CET 2007

Heikki Lindholm kirjoitti:
> Hello list,
> I took up some old dusty code of mine that uses snd_pcm_state followed 
> by snd_pcm_status_get_tstamp when in capture mode. The code used to 
> work, but now the returned timestamps are all zeroes. Is there some API 
> change done recently or is the whole timestamping deprecated or 
> something? I've tried with different drivers on ubuntu's alsa .14 and 
> gentoo's .14. I've also tried mmap'ed and r/w modes, and I'm setting the 
> TSTAMP_MMAP sw param.

I figured out that this doesn't happen when using hw:x,y devices. Is it 
a documented feature that some (software?) devices don't fill in timestamps?

-- Heikki Lindholm

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