19 Filenames   19.2 Pathnames   19.2.2 Interpreting Pathname Component Values   19.2.2.4 Restrictions on Examining Pathname Components

19.2.2.4.7 Notes about the Pathname Version Component

• Use positive integers starting at 1 as version numbers.

• Recognize the symbol :oldest to designate the smallest existing version number.

• Use keywords for other special versions.