Hi All,
Is there anybody out there who can help me to answer the following questions:
I have converted an application called Linrad ( http://www.nitehawk.com/sm5bsz/linuxdsp/linrad.htm ) from OSS to ALSA. Linrad is a remarkable DSP application used worldwide by many radio-hams.
I am facing hereby a problem with a "short read" :
An ALSA device is opened in blocking mode:
********************************************* err=snd_pcm_open(&rx_ad_handle, rx_sndin_plughw_pcm_name, SND_PCM_STREAM_CAPTURE, 0); ********************************************* When I subsequently read the device with following statement I sometimes get a "short read": ******************************************** err=snd_pcm_readi(rx_ad_handle,rxin_isho, rxad.block_frames); if((unsigned int)err != rxad.block_frames) { if(err == -EPIPE) // EPIPE, try recovery { err= snd_pcm_recover(rx_ad_handle, err, 0); if(err < 0)lirerr(1108); // recovery failed } else { if(err < 0) { lirerr(1113); // catch all } else { lirerr(1116); // short read } } } } **************************************************
Here are my questions:
1. How is it possible to get a "short read" in blocking mode ? I would think that in blocking mode the control is only returned after the read is completed.
2. What are the possible causes for a "short read" ?
3. What can be done to avoid a "short read" ?
4. How am I supposed to recover from a "short read"?
Best regards,
Pierre Vanhoucke/ ON5GN