Samba3 VFS: Opaque vs. Transparent.

Christopher R. Hertel crh at
Fri Jan 11 19:20:57 GMT 2008

Thanks, James.

So, if I understand you correctly...

- Calling SMB_VFS_NEXT_XXXX() from a function marked Opaque would have
  no effect.

- *Not* calling SMB_VFS_NEXT_XXXX() from a function marked Transparent
  would effectively make that function opaque.

Let me know if I'm close.  I have situations in which I may need to
optionally call the NEXT function in the chain so.  If I have this right, I
would want to mark those functions as Transparent and only call the NEXT
function when needed.

Thanks again.  That helps a lot.

Chris -)-----

James Peach wrote:
> On 11/01/2008, Christopher R. Hertel <crh at> wrote:
>> For those with Samba3 VFS experience:
>> I am trying to wrap my brain around the workings of Opaque vs. Transparent
>> functions.  So far, I understand that calling SMB_VFS_NEXT_XXXX() is also
>> involved in the opaque/transparent question.
>> Here's what I don't yet understand:  What effect does setting
> This prepends the function pointer chain of VFS operations that you
> traverse using SMB_VFS_NEXT
>> have on VFS function behavior.  What different
>> effect does SMB_VFS_LAYER_OPAQUE have?
> This resets the function pointer at the fixed end of the VFS operation
> chain, ie. the chain always has a known last operation, which is set
> by the most recent OPAQUE function.

"Implementing CIFS - the Common Internet FileSystem"    ISBN: 013047116X
Samba Team --    -)-----     Christopher R. Hertel
jCIFS Team --  -)-----  ubiqx development, uninq
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