Reading Files on a CD/DVD-ROM without proper permissions

meb495 · 01-21-2007, 12:23 PM

Very simple problem really, perhaps someone has a simple fix:

I have many burned DVDs with AVI files that I burned using OS X and thus, I suppose, the files on them have Unix-style permissions. When I burned them I didn't much care about permissions because at the time I wasn't a Linux user.

Now I find that I can only read (play, copy, etc) files on these DVDs if the permissions are set to allow people other than the owner to read them - very, very few are.

I tried using the sudo cp command from the terminal to copy the files onto my hard drive using my own root status. This neither worked nor produced an error. Perhaps I did something wrong?

I also added nosuid to the cdrom entry of my fstab at the suggestion of someone on Ubuntu's forums. That didn't work either.

Perhaps I should just blame Apple for letting me burn a DVD with wacky permissions in OS X.

I'm new to Linux and Ubuntu but truly love Ubuntu so far(I'm running Edgy Eft), having used Red Hat, Mandriva, and Linspire in passing. Please, someone, is there simple way around this problem short of using a Windows box or a Mac to access the files?

Thanks,
User with a new Ubuntu desktop

Matir · 01-21-2007, 12:39 PM

You could copy the files to your computer and then use chmod to change the permissions on the files to allow everyone to read.

Emerson · 01-21-2007, 12:48 PM

Also you could create an user in Linux with same UID (501 probably?) as your Mac user had to gain access to those files.

meb495 · 02-01-2007, 05:26 PM

I tried that, creating a user with the name 501. Ubunutu won't let me create a UID of just 3 numbers. oh well

meb495 · 02-01-2007, 05:27 PM

Also tried the other suggestion, copying the files and running chmod. I can't do that because I don't have the permissions to copy the files in the first place.

Robhogg · 02-01-2007, 05:41 PM

What would happen if you added uid=<your uid> to the options in fstab? According to the man page for mount:

Code:

Mount options for iso9660
...
 uid=value and gid=value
              Give all files in the file system the indicated  user  or  group
              id,  possibly overriding the information found in the Rock Ridge
              extensions.  (Default: uid=0,gid=0.)

Edited to add:
There's also a mode=value option listed in the man page, which can set permissions using octal values. Not tried either of these, because I've never needed to, but it may work.

Emerson · 02-01-2007, 06:33 PM

Quote:

Originally Posted by meb495

I tried that, creating a user with the name 501. Ubunutu won't let me create a UID of just 3 numbers. oh well

It certainly is possible manually. Edit the passwd file if everything else fails.

Quakeboy02 · 02-01-2007, 06:54 PM

"Also tried the other suggestion, copying the files and running chmod. I can't do that because I don't have the permissions to copy the files in the first place."

The root user has permission to do anything.

Matir · 02-01-2007, 09:39 PM

And you want a UID of 501, not a username.

meb495 · 02-03-2007, 02:18 PM

Thanks Robhogg, adding my UID and GID to the fstab entry for my DVD drive worked perfectly! I recommended that as an option for others in a similar situation.

As for my failed attempt to copy the files to my hard drive as root, perhaps I did something wrong there, being a newbie and all. . .I'll try that one again sometime to improve my Linux skills.

For now I'm grateful to have access to all my movies. Thanks.