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Directory hard links

We have decided to violate the strict interpretation of usual UNIX file system semantics in favor of reliability and simplicity and not allow multiple hard links to directories, so determining proper directory reference counts is relatively easy. The Linux VFS layer has never supported multiple directory hard links, and all modern UNIX implementations at minimum restrict such a capability to the superuser due to the damage directory cycles can cause.

Valerie Henson 2006-10-18