-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Jan Engelhardt wrote:
On Oct 17 2007 16:01, G T Smith wrote:
You do not need dd (or mount), tar with with the DVD/CD device name as target does it nicely for reading (and writing). I would expect multi-volume tar to work in the same way as it would with a tape device in this scenario...
That only works with certain writers and discs. DVD+RW for sure, DVD-RAM. No idea about DVD+R. CD-RW in packet mode maybe. Use of pktcdvd is advised because its buffering is just advantageous (too lazy to search for details), and it may (or may not - who knows) solve the Read-Only problem.
Stupid DVD drives die after exactly 2 years and 1 month, and I've hit that timespan again so can't check.
Yep, the drives are almost as disposable as the media :-)
One can effectively treat a writeable DVD/CD as datastream media (i.e. like a tape Basically the track layout is the same as that of a vinyl record, a long spiral, not a block and sector layout like a floppy or HD..).
But when not in packet mode, you need to update the TOC. And the kernel does not do that for you.
Tar was originally designed to work with tapes where this is kind of table of contents issue is best handled differently, so I do not think this is an issue with raw tar format. I hear some have managed to mount DVD media as read write filestore but I have never suceeded with my attempts. I think you a right in saying it is only certain hardware which will allow this, and I would expect problems with write once media, and agree that DVD+RW in the absence of DVD-RAM is the most data friendly medium. Packet writing would be really nice, but again not all hardware has reliable support... multimedia burners do not have worry about this stuff but for data burners this is highly desirable... I am a bit bemused by my observation that my old device (now having done its 2years and 1 month) worked with tar -c, but my new device does not work with it (only writes first block) but it will write with tar -cz I do get an I/O error on retrieving data that looks like it is probably an EOF/EOS related error and I can still retrieve data, but I must admit I prefer to use growisofs as it does a couple of useful checks so I am less likely to do something silly like zap an iso image through absent mindedness. - -- ============================================================================== I have always wished that my computer would be as easy to use as my telephone. My wish has come true. I no longer know how to use my telephone. Bjarne Stroustrup ============================================================================== -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFHFlUXasN0sSnLmgIRAnr2AKDLtbrwafCyM+8lpGF2Vyl7wuwiRQCZAfqB yOoRuGleb2F95WAuQfd0foc= =j+Rj -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org