makemkvcon backup does not work for ISO source?

[joe42]

Is there a reason that

Code: Select all

  makemkvcon backup iso:sourcefile.iso /dest/dir/

does not work? It fails with the message

Code: Select all

  Backup source must start with "disc:"

However, makemkvcon is perfectly capable of using the same ISO file for a source with

Code: Select all

  makemkvcon info iso:sourcefile.iso

and converting to an mkv with

Code: Select all

  makemkvcon mkv iso:sourcefile.iso all /dest/dir/

I do not understand why makemkvcon fails on backup for ISO sources, but works with info or mkv.

By the way, I am just wanting to extract the files from a blu-ray ISO (already decrypted) with UDF 2.5 or 2.6 filesystem, without requiring root privileges to use mount -o loop -t udf sourcefile.iso . None of the usual userspace tools can do it (7zip, bsdtar, fuseiso) since they do not support UDF 2.5 or 2.6.