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Re: dvd multi-session

> is there anyway to have growisofs format the entire media as an iso9660
> filesystem?

Yes, if you fill it all up with files ;)

> if so, will i be able to mount it read/write?

No. The iso9660 filesystem driver does not support writing to the
filesystem. The filesystem has to be ready-made (by mkisofs) and is then
written/appended as disk image to the disk.

> essentially
> treating it as a hard drive.

This is what Andy's kernel patch is good for. You can use any filesystem
with it, as long as the filesystem itself supports writing. iso9660 is
the only one which doesn't, its design doesn't allow for this scenario
so it's not just not implemented, it's not possible. That's why udf was

The catch of the "you can use any filesystem (except iso9660)" is that
filesystems are not optimised for this type of use, and performance will
be very poor. From a practical point of view performance is close to
useless, unless you only make small changes. Test it yourself if you
want to know for sure. As previsously discussed, udf is supposed to fix
this, but my own results with Linux-udf are that it is only somewhat
better than ext2 in a few cases, and beyond any stretch of usable in
others. You are also "paying" in other costs, e.g. its bugs.

In summary, Andy's patch is mega-cool, but of only limited practical
use because of a lack of a filesystem which is usable with it. Sad, but
the current state.

Your best bet for backing up new files is to use iso9660 and growing
that by adding new files to it. Forget about tar.

Alternatively, as I said before and as hard disks are cheap, you can
read a dvd as disk image to hard disk, enlarge the filesystem, muck
around with the files on it to your likeing, burn the filesystem back to
dvd. Ext2 is a good choice for this. If you read the files from dvd
often you want to optimise the ext2 at least a little, this can be
scripted (I have mostly done this).

I am unsure what the advantages of readcd are over dd for reading
filesystems to hard disk.

If an iso9660 is grown with growisofs, does isoinfo -d report the new
size correctly?


Volker Kuhlmann			is possibly list0570 with the domain in header
http://volker.dnsalias.net/		Please do not CC list postings to me.

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