snd_pcm_status 503 include/sound/pcm.h int snd_pcm_status(struct snd_pcm_substream *substream, snd_pcm_status 504 include/sound/pcm.h struct snd_pcm_status *status); snd_pcm_status 531 include/uapi/sound/asound.h #define SNDRV_PCM_IOCTL_STATUS _IOR('A', 0x20, struct snd_pcm_status)