sorry for the late, but I've been busy. After burning some CDs and doing some test I have learned this:
*short version If the CD-ROM was burned with "DAO" option (Disk At Once) then dd or any other program (cdio, readcd, etc) will not report any problem. If TAO mode was used, then you will have problems with the end of the dump. *long version When doing "dd if=/dev/rcd0c of=myfile.iso bs=32k" I was having a message from kernel: "Check condition error 0x70". This means "dd" is trying to read beyond the end of the track and it can't so return that error (and also kernel message) no matter if bs option was 2k or 32k. I was confused because I some CDs did that, and others don't. As cdio and readcd were having exactly the same issue, i understood that it's not a "dd" problem. And also I had the same behaviour on other PC, with exactly the same CD-ROMs, so the hardware issue was discarded. Then I noticed that the CDs burned as DAO (cdrecord with -dao option) were the ones wich hadn't the problem. I burned some CD-ROMs with the same data with and without the TAO option and now I'm sure that's the cause. My problem trying to create an ISO file from a Nintendo Wii is a completely different issue.
