[alsa-devel] Problems with snd_pcm_wait(..)

[Markus Luttenberger]

Hey,


I tried to implement a callback functionality with ALSA based on the 
example given at 
http://www.cs.utk.edu/~vose/linux/equalarea.com/alsa-audio.html#interruptex. 
Especially the while-loop is basically the same in my program. However, 
it doesn't work. I can trace the program to snd_pcm_wait(..) which just 
waits endlessly.

The whole thing is called within a thread. The thread is still 
accessible from elsewhere in the pogram. It's just the 
snd_pcm_wait(..)-function which does not return although a time-out of 
1000 ms is given.

If I don't wait for the device I get the following assertion:
pcm.c:1079: snd_pcm_writei: Assertion `size == 0 || buffer' failed.

Any ideas what could be wrong?




greetings..
..Markus