On 11/08/2011 04:47 PM, Yaroslav Panych wrote:> Greetings
>
> I have found next paragraph in Licence file(source root)
> "Digium, Inc. (formerly Linux Support Services) holds copyright
> and/or sufficient licenses to all components of the Asterisk
> package, and therefore can grant, at its sole discretion, the ability
> for companies, individuals, or organizations to create proprietary or
> Open Source (even if not GPL) modules which may be dynamically linked at
> runtime with the portions of Asterisk which fall under our
> copyright/license umbrella, or are distributed under more flexible
> licenses than GPL."
>
> What does it mean? Does it mean I can write non-GPL modules(BSD, MIT,
> etc)? Can I build my modules in common asterisk source tree(i.e. using
> LOCAL_MOD_SUBDIRS="my_mod_subdirs_list" make ) or must use
separate
> tree? If so, then since Asterisk core does not accepts anything except
> AST_MODULE_INFO(ASTERISK_GPL_KEY, ....) what I should do here?
Asking for people on this list to tell you what 'this means' is like
asking people on this list to tell you what is wrong with you if you
have a headache and a fever; you will get answers, but they won't be as
useful as if you asked an expert in that field of inquiry :-)
In spite of that, I'll give you Digium's interpretation of what that
paragraph means and attempt to answer your questions. Since Digium is
the 'licensor' in this equation, our opinion certainly carries some
weight, but you should consult with your own legal counsel in order to
determine whether the actions you wish to take are compatible with the
license terms or not.
The paragraph you quoted above doesn't directly grant you any rights at
all; it is only a statement that Digium can, and does, grant third
parties the ability to produce and distribute works that could be
classified as 'derivative works' of Asterisk without being subject to
the provisions of the GPL version 2 (as they would otherwise be, since
most people receive Asterisk under that license). If you have a need for
such a license, you should contact Digium to inquire about it.
As far as your other questions go, they are fairly vague, but I can
attempt to answer them:
* The GPLv2 places no restrictions on what you can 'write', it only
places restrictions on your distribution of things that you write that
could be considered 'derivative works' of a GPLv2-covered work (in this
case, Asterisk). If you write something that could be considered a
derivative work, and you wish to distribute it, then the GPLv2 obligates
you to distribute that work under the GPLv2 or a compatible license.
Most versions of BSD-style licenses, the MIT license, and many others
are GPLv2 compatible. Many open source licenses are not; the Free
Software Foundation maintains a page on their website covering this topic.
* The GPLv2 places no restrictions on how you build your works, where
you place the source code, or anything of the sort.
* The module loader in Asterisk, as distributed by Digium under the
terms of the GPLv2, does make a simple check to ensure that modules that
are being loaded into a running Asterisk instance claim to be licensed
under the GPLv2 (or a compatible license) themselves. This is an effort
to ensure that someone distributing such a module will be aware that
they need to consider the license under which they distribute it. If you
want to produce your own modules and distribute them inside your
organization without putting the ASTERISK_GPL_KEY into them (although
for distribution inside your organization this won't really make much
difference), you can certainly modify the module loader to skip this
check (you do have the source code, after all).
--
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at www.digium.com & www.asterisk.org