ssip: Speech Output Control Commands
4.2 Controlling Speech Output
=============================
These commands can stop or resume speech or audio output. They all
affect only the synthesis process and output to a sound device, they do
not affect the message history.
'STOP { ID | all | self }'
Immediately stop outputting the current message (whatever it is --
text, letter, key, or sound icon) from the identified client, if
any is being output. If the command argument is 'self', the last
message from the current client connection is stopped. If it is
'all', stop currently output message or messages from all the
clients. Otherwise, argument ID must be given as a positive
integer and the currently processed message from the client
connection identified by ID is stopped; if there is none such, do
nothing.
'CANCEL { ID | all | self }'
This command is the same as 'STOP', with the exception that it
stops as yet unspoken output messages as well. All currently
queued messages are stored into the message history without being
sent to the audio output device.
'PAUSE { ID | all | self }'
Stop audio output immediately, but do not discard anything. All
the currently speaking and currently or later queued messages are
postponed and saved for later processing, until a corresponding
'RESUME' command is received.
The meaning of the command arguments is the same as in the 'STOP'
command.
'RESUME { ID | all | self }'
Cancel the effect of the previously issued 'PAUSE' command. Note
that messages of the priority "progress" and "notification"
received during the pause are not output (but they remain stored in
the message history).
It is an error to send the 'RESUME' command when the output
corresponding to the given argument is not paused by a previous
invocation of the 'PAUSE' command. Such an error is signaled by a
'4XX' return code.
The meaning of the command arguments is the same as in the 'STOP'
command.