[alsa-devel] ALSA OSS Emulation - Read - EAGAIN Errors

[Takashi Iwai]

At Wed, 30 Jul 2008 08:20:09 -0700 (PDT),
Rahul Iyer wrote:
> 
> Hi ALSA Developers
> 
> 
> I have a full duplex voice application, that records voice and sends
> (over a network) as well as receives and plays voice. OSS APIs are used
> to capture and play voice samples. 
> 
> The voice quality is noticeably poor in SUSE 10. After further
> investigation, I see most of the 'read' system calls fail with EAGAIN
> (resource unavailable) error.

EAGAIN is no fatal error but means that samples are not available for
read when the stream is opened in non-blocking mode.  If it happens so
often, it's likely a parameter mismatch.  For example, the read period
size apps expected doesn't match with the size actually set.

It's better to create a small test-case first then analyze the problem
with it.


Takashi