As far as I can tell (any help here, anyone?) "port" has no such
option -- every package could have its contents in a different place.
Every package _could_ do that, but it's in the interest of the maintainers not to, because nobody wants to be adding a kajillion directories to their PATH, LD_LIBRARY_PATH, etc. IIRC, on BSD, port-installed stuff defaults to /usr/local/{include,lib}, while I believe MacPorts defaults to /opt/local/{include,lib}. So as long as you have those directories in the appropriate envars configure should be able to find stuff you installed that way.
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