Aha! Good tip, thank you. I didn’t know this but was starting to work it out from the background processes I later found lying around. Too much exposure to TOPS-10, VMS and NT, CP-M and so on, where I was used to ctrl-Z for EOF in case it might have terminated its reading of an input stream from the console, to persuade it that all was done, and then I tried ctrl-C based on 1970s / 80s thinking.
All these years, doing VMS for seven years or so I never had a *nix box to play with, not until recently. That’s why it’s enjoyable, picking up new things while also taking me back to the end of the 1970s.