Re: [Bug-xorriso] ISO-Disc not recognized

[Thomas Schmitt]

Hi,

> $ mkudffs delmeimage.img
> [...]
> start=256, blocks=1, type=ANCHOR
> start=976305, blocks=1, type=ANCHOR
> start=976561, blocks=1, type=ANCHOR
> There a several Anchors,

It does not report the 59 copies which i read from ECMA-167.
Just those at positions 256, n-256, and n. (I guess n=976561)


> it's really the best to overwrite the whole disc.

Which can last quite some time.

One could try to be scientific by determining the value
of n (the size of the UDF filesystem). Then one could use
the random access capabilities of BD-RE.

  dd if=/dev/zero bs=2048 count=1 | \
    xorriso -as cdrecord \
        -v dev=/dev/thedvdwriter stream_recording=on \
        padding=0 \
        write_start_address=256 \
        -

The same for n = 976561:

        write_start_address=976561 \

and n - 256:

        write_start_address=976305 \

Be aware that this is not guaranteed to overite only the
targeted block, although padding=0 should avoid the most
coarse colateral damage. libburn usually writes full DVD
ECC blocks of 32 kB resp. BD Clusters of 64 kB.


Even more scientific would be to peek into the code of the
mounter in order to learn which pitfalls it fails to avoid.


Have a nice day :)

Thomas