no need for cd

[Scott Schwartz schwartz@galapagos.cse.psu.edu]

serge writes:
| (Didn't the Plan9 people say that mount entries are hashed,
| so that ".." can refer to arbitrary directories, depending on what
| you've mounted?  E.g. this won't change any semantics.)

Yes, they did.  I find the idea of ".." in a union mount directory
confusing.  It certainly breaks e.g. tar.  A nice file tree walk
library could at least encapsulate strategies for avoiding lossage,
but if your filesystem is not a tree, is having ubiquitous ".."
entries the right thing?  Maybe "set default prefix" is a better
abstraction.  [My plan 9 manpages are stored in an old VMS binder;
there must be leakage.:-)]