[Samba] Re: How Samba let us down

[Matthew Hannigan]

On Thu, Oct 24, 2002 at 02:10:14AM +0000, jra at dp.samba.org wrote:
> On Wed, Oct 23, 2002 at 09:02:03PM -0500, Steve Langasek wrote:
> > On Thu, Oct 24, 2002 at 11:38:55AM +1000, Matthew Hannigan wrote:
> > 
> > > I have read in the docs that Samba locks and Unix locks
> > > _DO_ notice each other, with the caveats that Unix lock
> > > daemons are sometimes buggy and that Unix locks can only
> > > lock the first 2^31 bytes of a file.
> > 
> > > Please tell me that they do in fact notice each other.
> > 
> > Oplocks are not part of the traditional lock semantics available on
> > Unix.  If you aren't running a kernel (Irix or Linux) that implements

And Solaris?  At least they're autoconfigured to assume kernel oplocks
according to testparm, and the docs say this is done only if the support
is there.


> > oplocks, you MUST NOT use oplocks if the files will be accessed by
> > applications other than Samba.
> 
> Don't confure the two. Oplocks are nothing to do with share
> modes or byte range locks. They're just unfortunately named.

I'll try not to confuse the two :-)

So 'oplocks' and real locks are or are not noticed by other unix processes?

What is the best document to learn about how Samba does
it's locking?

I did have a look at the docs really, but textdocs/UNIX-SMB.txt
for instance says that "Unix has no simple way of implementing
opportunistic locking, and currently Samba has no support for it."

Which is out of date I guess.  

What is the best document to learn about how Samba does
it's locking?

Replies of the form "read the source Luke!" are ok; at least
I'll know to stop searching elswhere.


Regards,
Matt