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Some thoughts on Joliet - why it is a dumb idea to have a CD
with Joliet enhancements but without Rock Ridge.
It also helps you to understand why it it not possible to append
a new session to a multi-session Joliet CD when Rock Ridge is
missing.

-	Joliet is not an accepted independant international standard
	like ISO-9660 or Rock Ridge (IEEE-P1282).
	Joliet has been created in 1995 - Rock Ridge in 1990.
	Rock Ridge became a IEEE standard around 1992.

Joliet is an unjustified addition to ISO-9660.

-	The Joliet tree has no relation to the
	ISO-9660 tree. Files from the ISO-9660 tree and from the
	Joliet tree only share content. In general, it is not
	possible to find the ISO-9660 name from a Joliet name
	and vice versa if you check both trees on a CD.

	Rock Ridge extensions are located at the end of each
	ISO-9660 directory record. This makes the Rock Ridge
	tree closely coupled to the ISO-9660 tree.

-	Joliet does not allow all characters too, so the
	Joliet filenames are not identical to the filenames
	on disk.

	As the ISO-9660 tree is the standard reference tree
	on a CD and the ISO-9660 filenames don't allow all
	characters and there is a length limitation, the
	ISO-9660 names cannot be mapped to the filenames on the
	OS reference tree on disk for doing multi-session.

	Due to different limitations, the short ISO-9660 name 
	is in most cases not equal to the Joliet name or the
	Rock Ridge name.

-	Joliet has a filename length limitation of 64 chars (independent
	from the character coding and type e.g. European vs. Japanese)
	This is annoying as modern filesystems all allow 255 chars
	per path name component.

	Joliet uses UTF-16 coding while Rock Ridge uses ISO-8859 or
	UTF-16 based chars and allows 255 octets. Using UTF-8,
	Rock Ridge allows 85 Japanese characers or 255 US-ASCII chars.

Other than slightly longer filenames, Joliet offers no new properties
over plain ISO 9660. Rock Ridge is an open extendable standard and
there is no filesystem property on Win32 that could not be implemented 
using Rock Ridge.

Except Linux and FreeBSD, there is no POSIX-like like OS that supports
Joliet. Never create Joliet only CD's for that reason.