[alsa-devel] Any issues with GETOSPACE OSS ioctl?

I have a customer who reports that when his OSS application makes several write() followed by SNDCTL_DSP_GETOSPACE, the returned value is not decreasing, which implies that the write() commands are not going through.

I've looked at the OSS documentation for this ioctl (http://manuals.opensound.com/developer/SNDCTL_DSP_GETOSPACE.html), and it implies that it is not reliable. But since the customer is using ALSA (i.e. ALSA's OSS emulation), I don't know if that applies.

So I'd like to know how the 'bytes' return value is calculate in ALSA.