title: Wait until playback has completed
body: <p>I'm using PortAudio as a front-end to a speech synthesis (Text to Speech) engine, and I want to provide a synchronous speak function that waits until playback has completed.</p>
  
  <p>It seems like all of the PortAudio functions that deal with this only wait until the underlying API has finished consuming the audio data, not until playback has finished.</p>
  
  <p>Is this possible with PortAudio? If not, are there any good cross-platform alternatives to PortAudio (has to include a C interface) that might support this?</p>