How to burn read and write files on DVD

Question

I would like to know how to burn DVDs (image files) with the Read and Write setting. I have changed the settings in Get Info for the image files to Read and Write for Owner, Group and Others and yet when I burn the DVD and try and copy the files back onto the hard drive (to test if it works or not) it won't allow me. When I check the Get Info it says Read and Write for owner (greyed out) and Read Only for Group and Others (greyed out too).
I have also tried to change the status of the blank DVD before adding files and after adding the files (but b4 the burn) to Read and Write, this works but then during the burn process the DVD or burner changes my settings to Read Only.
I am burning with Finder and have tried with Toast 10 Titanium. What am I doing wrong, or not doing at all?! I'm going loopy with frustration!

Answer 1

Kiraly, I agree that the actual problem here might be something else, but as a side issue there seems to be a difference in the way permissions are handled when a file copy is made using Finder compared to when the copy is made using the cp copy in Terminal. At least in my Tiger system, Finder preserved the permission structure, though not the ownership, when it copied a file, whereas cp used the OS defaults.
I tried the following experiment:
From my test user account "t", I created a textfile named ReadWrite.txt, and gave it Read+Write permissions for Owner, Group, and Others. I then burned it using Finder to a DVD which I named PermissionTest, and then unchecked the "Ignore Ownership" box on PermissionTest.
The original ownership and permissions were preserved on the DVD, though of course you couldn't actually write to anything there:
xxG5-Computer:~ t$ ls -l /Volumes/PermissionTest/ReadWrite.txt
-rw-rw-rw- 1 t t 15 Sep 13 18:25 /Volumes/PermissionTest/ReadWrite.txt
I then copied the file from the DVD to the Desktop using Finder, and the permissions were preserved!
Finder copy:
xxG5-Computer:~ t$ ls -l /Users/t/Desktop/ReadWrite.txt
-rw-rw-rw- 1 t t 15 Sep 13 18:25 /Users/t/Desktop/ReadWrite.txt
I then trashed the Finder copy of ReadWrite,txt on the desktop, and made a second copy from the DVD, but this time I used the cp command from Terminal instead of using Finder. This time the permissions were not preserved, but reverted to the OS default:
cp copy:
xxG5-Computer:~ t$ cp /Volumes/PermissionTest/ReadWrite.txt Desktop
xxG5-Computer:~ t$ ls -l /Users/t/Desktop/ReadWrite.txt
-rw-r--r-- 1 t t 15 Sep 13 19:43 /Users/t/Desktop/ReadWrite.txt
I then switched to a different user account "t1", and repeated the above with the same DVD, first copying the ReadWrite.txt file to the desktop using Finder, and then using cp. The ownership of the copied file changed from t to t1 in both cases, but the permission structure again was preserved in the Finder copy but not in the cp copy:
DVD file:
xxG5-Computer:~ t1$ ls -l /Volumes/PermissionTest/ReadWrite.txt
-rw-rw-rw- 1 t t 15 Sep 13 18:25 /Volumes/PermissionTest/ReadWrite.txt
Finder copy:
xxG5-Computer:~ t1$ ls -l /Users/t1/Desktop/ReadWrite.txt
-rw-rw-rw- 1 t1 t1 15 Sep 13 18:25 /Users/t1/Desktop/ReadWrite.txt
cp copy:
xxG5-Computer:~ t1$ cp /Volumes/PermissionTest/ReadWrite.txt Desktop
xxG5-Computer:~ t1$ ls -l /Users/t1/Desktop/ReadWrite.txt
-rw-r--r-- 1 t1 t1 15 Sep 13 19:51 /Users/t1/Desktop/ReadWrite.txt
I got similar results when I tried copying a file with Read+Write permissions for all from a USB flash drive to the Desktop, again with the "Ignore Ownership" box unchecked.