Trigger other services on PPS activity

Any app
Note: This type of object is known as a server object, a special PPS object designed for point-to-point communication between a server and one or more clients. For details, see "Server objects" in the QNX Persistent Publish/Subscribe Developer's Guide.


You can use the ppsnetd service to watch any PPS object and have a client executable run when activity occurs on the watched object.
Note: The ppsnetd service cannot be running when the watch command is invoked. If it is running, you must stop the service, invoke watch, and then start the service again.

Message/response format

Commands sent to the /pps/services/ppsnetd/control object are of the form:


Responses always reflect the command_string and ID_number that were sent in the message, along with any errors:



msg:: id:: dat:json:
watch Number {"object":"<path_to_object>","exec":"<path_to_executable>"}
start Number n/a
stop Number n/a


res:: id:: dat:json: err:: errstr::
command (watch, start, or stop) Number (whatever was sent in id::) n/a errno_number as appropriate