Re: [Bug-xorriso] Mode 1/2, Form 1, XA, XA1, etc

[Thomas Schmitt]

Hi,

> I had a problem with CD-RW multisession with a BD-writer where a DVD-writer
> made no problems.

One of my BD writers (Optiarc BD-5300S) goes mad as soon
as i just insert a writable CD. If i then try to write to
a BD-RE, the drive performs the unique stunt of deformatting
the medium. It stays in this weird state until it gets a
power-off-power-on cycle.


> After some experiments I discovered that a missing -data and -tao
> switch in the burning command for the next session were the solution.

Now that's surprising.
There are several write types for CD. Most popular are
Track-at-Once TAO and Session-at-Once SAO. To my knowledge,
SAO is only possible with blank CDs. Not as add-on session.
So if the add-on run succeeded, it must have been TAO.

The write results of SAO and TAO differ by the sequence
of writing payload and Table-of-Content. SAO first writes
the TOC and then the payload tracks, according to the
written TOC. TAO first writes the payload track and then
updates the TOC.
CD is very bad with addressing particular sectors. So SAO
versus TAO might well make a difference with the first
session.

If the success with explicit -tao was not incidential,
then there must be some other side effect of option -tao
in cdrecord.

One can watch the very lengthy data traffic between
cdrecord and the drive by option -V.

  cdrecord -V -v ...other.options.but.no.tao... 2>&1 | tee -i /tmp/without_tao

  cdrecord -V -v -tao ...other.options... 2>&1 | tee -i /tmp/with_tao

If there is no significant difference to see in the files
/tmp/*_tao, then success and failure are incidential.
The BD is then at the edge of not recognizing a TAO
written TOC.

> The new volumename of the next session was visible on the
> desktopicon but not mountable in the BD-drive.

What kept it from being mountable ?
Are there any details to see in the system log files ?


> Today I test with xorriso/cdrskin and hope it works here too, because the
> handling is easier and its output messages are clearer for parsing
> in scripts.

If neither -sao nor -tao is given, both programs default
to SAO if the input size is predictable and the CD is blank.
Else they use TAO.
If you explicitely give -sao for an add-on session, then
they will refuse. Explicit -tao should be always applicable.


Have a nice day :)

Thomas