Date: Thu, 7 Jan 2010 20:50:22 +0100
From: Corinna Vinschen <corinna-cygwin@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: 1.7.1-1 noacl on samba share has incorrect directory write bit
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On Jan  7 13:42, Raman Gupta wrote:
> On 01/07/2010 01:02 PM, Corinna Vinschen wrote:
> >On Jan  7 00:39, Raman Gupta wrote:
> >>"Cygwin ignores filesystem ACLs and only fakes a subset of
> >>permission bits based on the DOS readonly attribute"
> >
> >No, it's a bit more tricky.  FAT filesystems, which are the role model
> >for noacl filesystems don't know something like a R/O directory.  The
> >DOS R/O bit on a directory does NOT mean the directory is R/O.  Rather,
> >it only means that the folder is some sort of special folder.  For some
> >better description, see http://support.microsoft.com/kb/326549.
> 
> Wow, isn't that just like Microsoft to reuse an existing read-only
> bit for something that is completely different semantically!
> 
> In any case, note that the KB article says that attrib *can* be used
> to see and modify the value -- as I demonstrated in my previous
> email.

Sure.  That has nothing to do with what I'm talking about.  While you
can set and reset the R/O bit on a dir, it doesn't have the *meaning* of
the directory being R/O.  If Cygwin reports such a directory as being
read-only from the POSIX perspective, certain functions would have
strange ideas and return EACCES, for instance.

> >Therefore the fault is not on Cygwin's side, but on Samba's side to use
> >the DOS R/O bit for something different than Windows uses it on
> >directories.
> 
> Understood. However, while Samba's use of the read-only bit on
> directories does differ somewhat from what Windows Explorer expects
> to use that bit for, it is a valid field and it does provide useful
> information to the client in the case of noacl Samba mounts.
> 
> Therefore, what would you think about configuring this via a mount
> option? For example, a per-mount setting called dro/nodro (directory

That's not the right thing to do, IMHO.  That's what the default "acl"
mount mode is for.


Corinna

-- 
Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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