---
title: kPreflightThenPause
framework: Application Services
role: symbol
role_heading: Enumeration Case
platforms: [macOS 10.0+]
path: applicationservices/1552213-control_flags_constants/kpreflightthenpause
---

# kPreflightThenPause

## Declaration

```occ
kPreflightThenPause = 4
```

## Discussion

Computes speech without generating.The `kPreflightThenPause` flagbit is used to minimize the latency experienced when the speechsynthesizer is attempting to speak. Ordinarily, whenever a callto `SpeakString`, `SpeakText`, or `SpeakBuffer` ismade, the speech synthesizer must perform a certain amount of initialprocessing before speech output is heard. This startup latency canvary from a few milliseconds to several seconds depending upon whichspeech synthesizer is being used. Recognizing that larger startupdelays might be detrimental to certain applications, a mechanism existsto allow the synthesizer to perform any necessary computations at noncriticaltimes. Once the computations have been completed, the speech isable to start instantly. When the `kPreflightThenPause` flagbit is set, the speech synthesizer will process the input text asnecessary to the point where it is ready to begin producing speechoutput. At this point, the synthesizer will enter a paused stateand return to the caller. When the application is ready to producespeech, it should call the `ContinueSpeech` functionto begin speaking.