Likely the best solution is for Speech Dispatcher to spawn its own instance of Festival, and the festival server to be extended/set up to communicate over a unix socket only accessible to the user who started Speech Dispatcher, as is done now between Speech Dispatcher clients and the Speech Dispatcher server.
Likely the best solution is for Speech Dispatcher to spawn its own instance of Festival, and the festival server to be extended/set up to communicate over a unix socket only accessible to the user who started Speech Dispatcher, as is done now between Speech Dispatcher clients and the Speech Dispatcher server.