Determines if any speech is currently being synthesized in your application or elsewhere on the computer.
- macOS 10.0+
The total number of speech channels currently synthesizing speech on the computer, whether they were initiated by your application or process’s code or by some other process executing concurrently. Paused speech channels are counted among those channels that are synthesizing speech.
This function is useful when you want to ensure that no speech
is currently being produced anywhere on the Macintosh computer before
initiating speech. Although the Speech Synthesis Manager allows
different applications to produce speech simultaneously, this can
be confusing to the user. As a result, it is often a good idea for
your application to check that no other process is producing speech
before producing speech itself. If the difference between the values
0, no other process is producing speech.