vfs-module lincense

[Jeremy Allison]

On Wed, Feb 27, 2002 at 12:35:09PM -0600, Esh, Andrew wrote:
> It seems to me that the copyright holders of Samba would have to make an
> exception for any libraries dynamically linked via the "vfs object" tag.

This is unlikely to happen.

> Otherwise, the external VFS interface cannot make use of non-GPL code. I
> think that's a severe limitation of the file systems Samba can use. I also
> think it completely obviates the need for an external interface. I thought
> the whole point of it being external is to allow non-GPL code to be used.

No, it's to make external modules easier to write and maintain (once the
VFS has stabilised somewhat). If you want to use non-GPL code, you'll
have to cross the process boundary, but even that is not 100% sure in
this particular case. I remember a particularly obnoxious company in the
Windows world who did a port of the GNU tools to Win32 which required
a proprietary licensed "server" component to implement some of the
reuired functionality. This was a separate process and the GNU tools
spoke to it via GPL code added to them by this company. The proprietary
server was license-managed of course.

I believe this was eventually ruled a violation and the company decided to
withdraw the product, rather than release their server code. The
reason for this was that the server component had no other use
than to be a technical "end run" around GPL requirements, it existed
for no other purpose, and was thus really part of the GPL system.

This is why the GPL is a *legal*, not a technical document. It is
designed to stop technical "cheats" to enforce the spirit of the
license, not just the current technical interpretation of the
day. Once you get comfortable with that and think "does this fit
with the *intent* of the license" then you'll be much happier.

For example, a vfs plugin that links to Oracle as a backend would
be GPL, but Oracle itself would not come under the GPL. This is
because Oracle is a program that is of itself functional without
Samba. However, a technical 'trick' to make a Samba specific hack
non-GPL using a separate process as described above may very well
be ruled to be under the GPL.

It's not a hard and fast rule, *usually* cross-process boundaries
are safe, but not *always*. 

Jeremy.