Hi All,
     Say hello to everyone!
     I'm a new member to learn how to write a ALSA application.
     I analyze the source code of aplay and very confused on follow interfaces:
            snd_pcm_playback_info()
            snd_pcm_playback_format()
            snd_pcm_playback_params()

     The aplay is belongs to alsa-utils that also is a application.
     It should be use interfaces of alsa-lib, but why i can't find these interfaces in alsa-lib ?
     Could you tell me where can find out these interface?

     Looking forward to your reply!

Best regards
Spring