If you want to send messages directly from the command line (e.g. from Nagios) to the Unipager, you can use a simple Python script.
It is available here: https://github.com/dh3wr/UniPager-SendWebsocket. Use the version unipager_send.py, if you want a flexible solution with command line arguments.
Just get the file from the github repository. You may need sudo apt-get install python-websocket in order to run the script.
usage: unipager_send.py [-h] [--hostname HOSTNAME] [--port PORT]
[--password PASSWORD] [--ric RIC] [--type TYPE]
[--func FUNC] [--msg MSG] [--debug]
Send paging call direct via Unipager
optional arguments:
-h, --help show this help message and exit
--hostname HOSTNAME The host running Unipager, default localhost
--port PORT The port Unipager is listening, default 8055
--password PASSWORD The Unipager password, default empty
--ric RIC RIC to send the message to
--type TYPE 0 = Numeric, 1 = Alphanumeric, default 1
--func FUNC Function Bits in POCSAG datagram, default 3
--msg MSG Message, if containing spaces: "TEXT WITH SPACES"
--debug Enable debug