svoid flite_say(S voice, S text) {
  if (!isOnPATH("flite")) fail("flite not installed");
  File f = javaxCachesDir("flite.wav");
  S cmd = "flite";
  if (nempty(voice)) cmd += " -voice " + voice;
  cmd += " -t " + platformQuote(text) + " -o " + platformQuoteOpt(f);
  backtick(cmd);
  lock voiceOutputLock();
  playWAVAndWait(f);
}