[Debburn-devel] iso9660 allow 8 level directory nesting, genisofs allow only 6?

[Zhang Weiwu]

Hello.

I've seen this question posted a lot of times on the Internet forums as
well as on usenet. People complain about their directory tree is more
than 6 level deep, get error message like this:

genisoimage: Directories too deep for './Data/profile/Mail/Local
Folders/Sent.sbd/2006.sbd/RealSS.sbd' (7) max is 6; ignored -
continuing.

And they are suggested either to use a filesystem with higher capacity
(-iso-level 4 or -R) or to remove directory depth restriction (-D).
Nobody seems to have asked should the max directory nesting level be 6.
Here the manual says:

        With all ISO9660 levels from 1 to 3, all filenames are
        restricted to uppercase letters, numbers and  under‐scores (_).
        Filenames are limited to 31 characters, directory nesting is
        limited to 8 levels, and pathnames are limited to 255
        characters.

As said, the directory level depth restriction is 8 level, not 6 levels.

I experimented with -J option, which is based on ISO and should allow
the same max directory depth; or if not, it should be written in
document which says "when -J is applied, directory nesting is limited to
6 levels".

I don't know which one is correct but I have the feeling either document
or the tool needs to be enhanced. Can someone share some insight on this
and wide knowledge available about it on the Internet?

Best regards
Zhang Weiwu