Security in Computing 5th Edition by Shari Lawrence Pfleeger, Charles P Pfleeger, Jonathan Margulies

Exercise 23

A problem with pattern matching is synonyms. If the current directory is bin, and . denotes the current directory and .. its parent, then bin, ../bin, ../bin/., .././bin/../bin all denote the same directory. If you are trying to block access to the bin directory in a command script, you need to consider all these variants (and an infinite number more). Cite a means by which a pattern-matching algorithm copes with synonyms.