On Wed, 21 Apr 2010, Stefan Schoenleitner wrote: > Stefan Schoenleitner wrote: >> Since a POLLIN event only occurs after at least a full period is available for >> reading (as set up by snd_pcm_sw_params_set_avail_min() above) >> and I only read after a POLLIN event occured on the capture device fd, >> I really do not understand why I get the above error. > > By using snd_pcm_avail_update() I found out that polling on the PCMs > *does not work at all*. > > Although I verified that avail_min is 160 frames, polling on the > capture/playback PCMs returns a POLLIN/POLLOUT event even if the number > of frames for reading/writing *is less than avail_main*. > > I also tried snd_pcm_wait() which should also wait until there are at > least avail_min frames available for reading/writing. > The result is the same: snd_pcm_avail_update() shows that it returns > even if there are far less than avail_min frames available for processing. > > I suspect that this is a bug in ALSA ? It might be. Could you post snd_pcm_dump() when you read less frames? Jaroslav ----- Jaroslav Kysela <perex@xxxxxxxx> Linux Kernel Sound Maintainer ALSA Project, Red Hat, Inc. _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel