We indicate that AFPBridge is installed by creating a message in the message center (which also includes its version, in case we want to distinguish between different versions in the future).
This avoids any possible strange behavior with calling Marinetti in P8 mode. It also ensures that I/O operations in P8 mode will give an error, but not terminate the connection: it will still be alive when we get back to GS/OS, unless the server has killed it due to inactivity (which is quite possible).
This can occur when control-reset is pressed in P8 mode. It’s supposed to reinitialize the AppleTalk stack. In our case, we mark connections to be reset once we're back in GS/OS, since we can't call Marinetti in P8 mode.
This only works if our init is loaded before Marinetti’s, because otherwise Marinetti’s shutdown notification procedure gets control first and shuts down the connection.
In that case, LoadOneTool returns an error, but the tool stub is still loaded, which is good enough (we just need its FPT to be loaded and installed in the TPT).