+ /// Plays a wave file (blocking).
+ ///
+ /// * `path`: wave file to transmit, must be 8 kHz mono and 16-bit LE
+ /// * `tx`: a `TxHandle` obtained from an `M17App`
+ /// * `source`: address of transmission source
+ /// * `destination`: address of transmission destination
+ /// * `channel_access_number`: from 0 to 15, usually 0
+ pub fn play(
+ path: PathBuf,
+ tx: TxHandle,
+ source: &M17Address,
+ destination: &M17Address,
+ channel_access_number: u8,
+ ) {