Past exam of the year 1 of the computer science course of the University of Oxford / 2014 / Digital systems, linear algebra, introduction to formal proof / 2 / a / Solution

Names live in directory entries. Each ordinary directory entry associates a component name with an inode number; the corresponding inode describes the file and locates its contents. A name is therefore not stored as the identity of the inode, and hard links can give one inode several names.

To resolve /var/mail/user, start from the root file-system directory's inode, read its directory entries and find var. Follow that entry's inode number to the var inode; read that file-system directory and find mail; repeat for user. The final inode supplies the file metadata and addresses needed to read the file data blocks. The intermediate file-system directories require search permission. This describes ordinary pathname traversal without a symbolic link or mount point changing the route.