Re: [dvd::rip] Read-only path is detected writable

On Mon, Apr 24, 2006 at 11:38:12PM +0200, Michael Müller 
<mueller_michael@xxxxxxxxxxx> wrote:
> Hi Jörn!
> 
> On Mon, Apr 24, 2006 at 10:19:05PM +0200, Jörn Reder <joern@xxxxxx> wrote:
> > Michael Müller wrote:
> > 
> > > dvd::rip (v0.52.6 and v0.97.8) detects under 'Global preferences' the
> > > 'Default data base directory' and 'Default directory for .rip project
> > > files' on a read-only mounted partition writable.
> > > 
> > > It seems that dvd::rip only looks at the access rigths. I'm using JFS
> > > as filesystem. I don't know if it is JFS specific that a read-only
> > > mounted partition doesn't loose the writable flag (I have no
> > > possibility to check with a different filesytem).
> > 
> > Hmm, dvd::rip checks directory permission with this expression:
> > 
> >   -d $dir && -w $dir
> > 
> > which looks Ok to me ;) To be sure it's no dvd::rip bug elsewhere, what
> > does this command print?
> > 
> >   perl -e 'my $dir="/opt/Multimedia/Filme/dvdrip/"; -d $dir && -w $dir && 
> > print "writable\n"'
> 
> It writes "writable".
> 
> > If this prints "writable" on a read only filesystem, we obviously hit a
> > bug either in Perl or in JFS. If not, I have to dig deeper into 
> > dvd::rip...
> 
> I will ask the maintainer of JFS. He always reponses fast.

I got no answer from the maintainer but a user anwsered. He checked it
on a USB drive and came to the same wrong result (I don't know the
file system he used). But this reminded me that I have a USB harddrive
too ;-) and I did the tests on a VFAT partition. Here I get the wrong
results too:

grizzly:/home/mm# mount -o ro,uid=1000 /dev/sdd5 /opt/MountPoints/USB-HD/
(Without uid=1000 'root' and not me will be the user of the mounted files)

mm@grizzly:~$ ls -l /opt/MountPoints/USB-HD/
...
drwxr-xr-x 11 mm root 65536 2006-04-06 07:45 Filme
...

mm@grizzly:~$ touch /opt/MountPoints/USB-HD/Filme/test-file
touch: kann »/opt/MountPoints/USB-HD/Filme/test-file« nicht berühren: Das 
Dateisystem ist nur lesbar
(translation of error message: 'Can't touch ...: The file system is read-only')

mm@grizzly:~$ perl -e 'my $dir="/opt/MountPoints/USB-HD/Filme"; -d $dir && -w 
$dir && print "writable\n"'
writable

So it seems that perl only looks for the access rights.

Is somebody reading the perl mailing list to report the problem?

Regards

Michael