Do I need a custom driver to do equivalent of netcat (nc) when virtual switch changes state?

[tony.fleisher]

The Maker API app can be used to post device events to an endpoint (the receiving end will need to handle the event format).
Details about this feature and the event format can be found here:

Maker API New Features

With Release 2.1.6 we are introducing a couple of new features to Maker API. Multiple parameters to device commands When sending a command to a device via an endpoint, it is now possible to specify multiple parameters for the command. These parameters go in the [Secondary value] field of the endpoint, and are separated by commas. Command parameters can be integer, decimal or string. It's up to you to be sure to use the correct type of parameter. Example sets a lock code for slot 3, code 43…