[SR-Users] Regd. Kamailio GPL

[Vicente Hernando]

On 03/12/2015 01:45 PM, Daniel-Constantin Mierla wrote:
>
> On 12/03/15 06:16, Alex Balashov wrote:
>> I am also not at all an expert in GPL licencing or IP, but would like
>> to add that any customisation you make specifically for the purpose of
>> interacting with a billing server or other external application is
>> likely to take the form of a Kamailio module, rather than
>> modifications to the existing Kamailio modules, the Kamailio core, or
>> any other part of the stock code tree.
>>
>> As far as I know, under the GPL--broadly speaking, for I certainly
>> don't know or remember the specifics--modules get different treatment
>> than modifications per se.
>>
>> As far sa I know, if you can stick your code into [a] completely
>> self-contained module(s) (and given what you've said about what
>> specifically you want to accomplish, it seems to me that you
>> absolutely can) that interact(s) with Kamailio using its module APIs
>> and requires no modifications to Kamailio itself, it's not subject to
>> the same licence constraints as modifications per se.
>>
>> Please do not take my advice as stated, and consult a competent
>> software/IP attorney.
> Modules have to be written in a GPLv2 compatible license, because GPLv2
> is 'viral' when linking the code, given that a module is using functions
> from core. If you do communication via socket/etc. with a different
> application, that application doesn't have to be GPLv2 compatible.
I recommend you to ask to FSF.

It is possible even when communicating via sockets to need to release 
your code under GPL.

In my point of view the difference is if your program works OK as a 
standalone application or if it needs the other
GPLed application to work. That works to defeat some ways to cheat GPL 
philosophy.

Regards,
Vicente.
> But again, the GPLv2 constraints are about distribution. If you write a
> module and keep it for yourself, then nothing is required by GPLv2. If
> you do a module and distribute it to someone else (free or with money),
> that someone has the rights to get the source code (for free or for
> money, but no more expensive that the binary form).
>
> Cheers,
> Daniel
>