19.2.2.4 Local Case in Pathname Components

For the functions in Figure~19–2, a value of :local for the :case argument (the default for these functions) indicates that the functions should receive and yield strings in component values as if they were already represented according to the host file system’s convention for case.

If the file system supports both cases, strings given or received as pathname component values under this protocol are to be used exactly as written. If the file system only supports one case, the strings will be translated to that case.