I don't see it. I don't see why you call this a design issue. Isn't
this just a case where they haven't gotten around to implementing
network and IPC mediation yet? How is that a design issue arising
from a pathname-based model? For instance, one system I built (Janus)
provided complete mediation, including mediation of network and IPC,
yet it too used a pathname model for its policy file when describing
the policy for the filesystem. That seems to contradict your statement.
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