Recently StanfordRoboticsClub shared on Github a collection of methods using a DualShock 4 PS4 Controller with UDPComms, which is a Python library to enable communication between different processes over a network using UDP (User Datagram Protocol) for developers. 
Download: JoystickUDP-master.zip / GIT
According to the README.md it currently works in Python, but should be relatively simple to extend to C to run on embedded devices like Arduino.
Rover
The library also comes with the rover command that can be used to interact with the messages manually.
Known issues:
Macs have issues sending large messages. They are fine receiving them. I think it is related to THIS issue. I wonder does it work on Linux by chance (as the packets happen to be in order) but so far we didn't have issues.
Download: JoystickUDP-master.zip / GIT
According to the README.md it currently works in Python, but should be relatively simple to extend to C to run on embedded devices like Arduino.
Rover
The library also comes with the rover command that can be used to interact with the messages manually.
| Command | Description |
| rover peek port | print messages sent on port port |
| rover poke port rate | send messages to port once every rate milliseconds. Type message in json format and press return |
Known issues:
Macs have issues sending large messages. They are fine receiving them. I think it is related to THIS issue. I wonder does it work on Linux by chance (as the packets happen to be in order) but so far we didn't have issues.
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