Can CD-RWs and DVD+/-RWs be mounted rw?

Question

@enzotib mentioned the following command

sudo mount -o remount,rw /cdrom

Does this imply I can mount a CD or DVD in rw mode and use like a (real) filesystem? Does this work with the popular ISO-9660 filesystem, which is read-only by design? Will this create a multsession CD with one session per change (or per mount)?

Would this work (differently) on a ISO image file on a read/write filesystem?

Answer 1

You can use UDF file system as packet writing and it effectively works as USB drive (or as diskette). See this link.

For example, BluRay discs as well as DVDs are usign UDF file system. You just need to make it with UDFtools and mount it read/write.

Answer 2

No they cannot.

To give a quick example why they cannot be mounted rw imagine mounting a blank cdr/cdrw, there is no file system on a blank cd, how do you specify one on mount then? How do you mount something to write on that has no valid file system?

Even nautilus with his integrated cd recording abilities does not follow that logic, the recording is not done automatically, it creates a tmp place to keep the files until you instruct to write them to a cd, blank or not.

Mounting a cdr/cdrw rw and writing on it as you with for example a USB disk is not possible.