Dumping a DVD with the new /rr argument potentially produces invalid dumps.

[maxz]

Version
20220301

Describe the bug
When trying to dump a DVD by using the new retry-on-error functionality (/rr) the resulting ISO is different than expected, when an error occurs. This results in dumps which are not properly comparable anymore and renders /rr useless.

I also tried fixing the images with EccEdc afterwards, but it did still not cause them to be equal to the correct dump.

Command-line text
DiscImageCreator_linux.out dvd /dev/sr0 ELEX_Disc1/ELEX_Disc1.iso 0 /q /rr 20

Disc title
ELEX Game Disc 1

Disc ringcode

Outer mastering code: DR1 ELEXPCSTEAM00001 @@    9/7/2017 10:03:33 PM    ID0001277224
Outer mastering SID: IFPI LY88
Inner mastering code: DR0 ELEXPCSTEAM00001 @@    9/7/2017 9:35:02 PM    ID0001277224
Inner mastering SID: IFPI LY88
Mould SID (data side): IFPI 128F

URL
https://eu.store.thqnordic.com/en/168/elex-collector-s-edition

Log file
This is the log of a correct dump without /rr: https://archive.org/download/redump.org-logs/ELEX_Disc1.zip
And this of a correct dump with /rr but without any errors occurring: https://archive.org/download/redump.org-logs/ELEX_Disc1-RR.zip
Dumping the disc with ddrescue produces an identical ISO image.
The correct SHA1 checksum for the final ISO is 493c80e30daeb3ae82638f3da1d4614985d68599.

These are two dumps using the /rr argument where errors were encountered and sectors were reread:
https://archive.org/download/redump.org-logs/ELEX_Disc1-RR1.zip
https://archive.org/download/redump.org-logs/ELEX_Disc1-RR2.zip

I also had the same problem with other discs, but this is the one about which I have the most information.

[saramibreak]

Try to use /f, plz. This flushes the drive cache.

Btw, do you have a Blu-ray drive? gmipf reports #110. If you are interested, see it, plz.

[maxz]

No, I'm afraid I don't have a Blu-ray drive.

I'm testing the /f option right now and will report back once I could verify whether it works.

[maxz]

So I tried to test this workaround for quite some time now, but I cannot get any of my DVDs to produce errors, except for one which produces so many that I had to abort the dump after three days of not finishing.

I will keep dumping with this option and report back as soon as I can finally verify whether this definitely works.