A bug and a couple of suggestions

[OzymandiasTheGreat]

First of all, this is awesome. I finally have shared clipboard between my Ubuntu 20.04 laptop and macOS Big Sur virtual machine, so thank you.

Now you should know that without the --secure option the app plain doesn't work. When passing -d
on both ends it shows that connection succeeded, reading clipboard succeeded, but nothing gets sent.
There's no communication between instances past the initial connection. No errors either.

With --secure it works as expected.

Now for the suggestions:

1. A better way to pass the secret to the app. Reading from stdin generally requires the app to be started interactively. I have absolutely no desire to do that. I run it on startup and as a workaround, I echo SECRET | uniclip.
2. Again, for an unattended startup picking a random port is downright silly. To work around this one, I pipe stdout to a file on a shared drive, then read and parse it on the remote machine, just so I know which port to connect to. Please add the --port option to make my life easier.