pub unsafe extern "C" fn snd_mixer_selem_get_playback_volume(
elem: *mut snd_mixer_elem_t,
channel: snd_mixer_selem_channel_id_t,
value: *mut c_long,
) -> c_int
pub unsafe extern "C" fn snd_mixer_selem_get_playback_volume(
elem: *mut snd_mixer_elem_t,
channel: snd_mixer_selem_channel_id_t,
value: *mut c_long,
) -> c_int