A host-built forge under a ceiling: its options may be narrower than the
ceiling, and then they narrow it; they may never be wider. Only the
capabilities the ceiling grants are compared, since the broker injects no
other. An intersection is taken in the ceiling's terms and never widens:
disjoint lists are wider, not empty. Read roots are compared after their
symlinks are resolved, the forge's and the ceiling's alike, since the
broker reads by real path: a forge root that is a link inside a ceiling
root to a directory outside it is wider. The narrowed roots are the
forge's, as it names them.
A host-built forge under a ceiling: its options may be narrower than the ceiling, and then they narrow it; they may never be wider. Only the capabilities the ceiling grants are compared, since the broker injects no other. An intersection is taken in the ceiling's terms and never widens: disjoint lists are wider, not empty. Read roots are compared after their symlinks are resolved, the forge's and the ceiling's alike, since the broker reads by real path: a forge root that is a link inside a ceiling root to a directory outside it is wider. The narrowed roots are the forge's, as it names them.