CD-RW changes all to root

Rashkae ubuntu at tigershaunt.com
Mon Dec 17 21:37:02 UTC 2007


NoOp wrote:
> Been awhile since I burned files to a CD-RW, but today I tried Nautilus
> CD Burner, GnomeBaker & K3b and while the files write to the CD just
> fine, all permissions on the CD get changed to root. CD, folders,
> files... everything to root. Any ideas on why this might be happening?
> 

This is expected behaviour, (and can be customized of course)

The logic is that, be default, a burned CD should be machine neutral,, 
ie, as a portable, removable device, you should be able to insert and 
use the CD in any computer.  Since the UID's only make sense for the 
computer on which the CD is burned, the default is to change them all to 
root.  This is, of course, customizable.

Sadly, I don't know how to customize those burning front ends you 
mention, but I'll show you how it works with mkisofs.  mkisofs is the 
the back end program that is used to create cd iso before (or while) 
they are burned to a CD.

The ISO9960 file system itself does not support User ID's, permissions, 
or filenames longer than 8 characters (+3 character extension).  Long 
file names, user ID and permissions can be added via the Rock Ridge 
extension on Unix system.  (Don't worry, adding the extension will not 
make the CD incompatible with other systems).  Rock Ridge will not be 
used by Windows, so you can also add Joliet extension if you want long 
file names to be available on Windows computers.

Rock Ridge is added by mkisofs with either -R or -r.  See the man 
mkisofs for a description of each.





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