jimmybobby wrote:The ideas situation is to ssh into both, and to see a string appear on both, from a python script.
What do you mean about seeing a string appear on both?
If you can ssh to both Pies, that suggests that they are connected to the same network. In that case the more Linuxy thing may be to have the Python programs communicate over the network instead.
Networking takes a bit more code than Serial to get started, but it is more flexible. You can have multiple programs using the network at the same time, and the kernel keeps track of the connections and which data to send where. Serial is just a sequence of bytes and you can only use it for one thing at a time. It is better suited for talking to single-task computers like Arduino.