That came later, though. Assuming re-purposing of an existing signal, SIGHUP was a smart choice because it's exactly the one that a daemon (not attached to a te

That came later, though. Assuming re-purposing of an existing signal, SIGHUP was a smart choice because it's exactly the one that a daemon (not attached to a terminal) will never ‘legitimately’ see. I don't know the history of SIGHUP-to-reload (perhaps a good question for TUHS) but I'd guess it originated outside of Bell or Berkeley, who would have simply added a new signal.