Originally Posted by Daedalus
Yes, sounds like memory protection. Are you depending on other software respecting that read-only status, or are you looking to enforce it? Enforcing it costs performance, so you're already at a disadvantage performance-wise compared to Amiga OS. If you're expecting software to be well behaved and respect memory flags, then you're basically no different to Amiga OS right now.
If the OS does it, it's memory protection. If the development system does it (as implemented in Oberon 2 or Mono) it's considered managed code. I favor the latter over the former (but more like Oberon 2 implementation where you can take off the "training wheels" or debug mode when you're ready for full performance).