[Box Backup] Additional information for Volume Snapshot Service (Shadow Copy)

Achim boxbackup@boxbackup.org
Mon, 29 Jun 2009 13:02:48 +0200


Hello List:

On Wed, 24 Jun 2009 21:54:47 +0400, Matthieu Patou <mat+bbackup@matws.net>
wrote:
> On 06/24/2009 10:14 AM, Chris Wilson wrote:
>> Hi Achim,
>>
>> On Tue, 23 Jun 2009, Achim wrote:
>>
>>> Meanwhile, in a licensing discussion over at the BackupPC list, it
>>> turns out (according to Leen, one of the original authors) that
>>> perhaps the "SDK just includes the include and library-files the
>>> compiler needs to know how to build it" [1].
>>>
>>> This would probably eliminate the issue anyway for GPL and BSD, as the
>>> libraries are then part of the OS and not a separate download.
>>
>> It doesn't eliminate the issue for GPL, because Microsoft's license
>> explicitly forbids linking any of their code against GPL code and
>> distributing the resulting binaries. However, BSD code does not fall
>> under that restriction.
>>
>> It's against the spirit of the GPL because it requires users to download
>> and use non-free software to rebuild their free software, in addition to
>> the non-free OS which they already have.
>>
>> Cheers, Chris.
> 
> I'm wondering how bacula do it with this limitation ?
> Because they are compiling with this library and their code is GPL.
> 
> I reread the licence for the VSS SDK and it's not really clear the 
> licence for those two libes in the lib directory (vss_uuid.lib and 
> vss_api.lib)

As I mentioned in another posting back in March 2009 [1], the Bacula
project gets around the GPL "restriction" (actually: liberations) by adding
a special clause that allows linking their GPL code with proprietary
libraries. 

A similar topic came up recently on the Bacula list again [2], and it
appears that perhaps there will be some progress towards having Free,
reverse-engineered header files. On the MingW list there is yet another
discussion on how to go about such a reverse-engineering process, and I can
see that Chris is actively participating [3].

It would be great if all the pieces would fall into place at some point,
however I believe that a practical "in the meantime" approach would be a
licensing exception, which, as Chris confirmed, would actually not even be
required for Box Backup's BSD-style license.

Best regards, Achim

[1]
<http://lists.warhead.org.uk/pipermail/boxbackup/2009-March/005126.html>
[2]
<http://www.mail-archive.com/bacula-devel@lists.sourceforge.net/msg04359.html>
[3]
<http://n2.nabble.com/Headers-for-free-distribution-like-for-win32api-td2724421.html#a2725427>