[aplusdev] Non-GPL A+?

[Derek Neighbors]

Alexander Skomorokhov said:
> Dan,
>   Is A+ available under a parallel, non-GPL commercial license
>   that would allow it to be used/embedded in non-open source
>   products? Perhaps something similar to MySQL's commercial
>   license?

You can sell GPL software[1], so I am not sure how it is non-commerical,
but I suppose that is splitting hairs.

>   GPL license is about A+ itself. If you take A+ source code and modify
> something there then this modification must be published under GPL.

Bzzzt.  Wrong answer.  You must only publish your changes under the GPL if
you distribute them.  If I download A+ and modify it to my hearts content
as long as I do not distribute this modified version to others, I am under
no obligation. [2]

> But if you use A+ as a programming language (and a platform to
>   develop your applications) then these programs and applications
>   may be proprietary. And you may use GPLed A+ in combination
>    with some proprietary products, let say MatLab.

If you write a program in A+, but don't modify A+ itself, certainly you
could license your program under whatever you like assuming there is no
"linkage" or inclusion of A+ code in the resulting program.[3][4]

>   As integrators of custom trading solutions, we cannot use
>   GPL licensed software because of potential license conflicts
>   with other software packages we integrate in our systems.
>   Let say I develop "close" source commercial system using commercial
> version of Dyalog APL. Most code is in APL, but I use MySQL as a
> database engine (and communicate to APL via ODBC) and use R to
>   perform some statistic calculations. In my (solid:-) understanding
> until I do not touch source code of MySQL and R (just use them as is)
> I am in good shape. And my commercial code written in Dyalog APL
>    remains close and protected.

If you wanted to modify MySQL and R you could do this with no worries as
long as you didn't "distribute" the resulting program. [2]  Furthermore, I
don't see how any of your Dyalog APL code would be at risk.  Only the
resulting program would be at risk.  The authors of MySQL and R could tell
you that you have two choices.

1. Make your program licensed under something GPL compatiable.
2. Stop using MySQL and R.

They can not "force" you to do #1 as far as I know.  They can force you to
do #2 if you don't do #1.

Derek Neighbors

[1] http://www.gnu.org/licenses/gpl-faq.html#DoesTheGPLAllowMoney
[2] http://www.gnu.org/licenses/gpl-faq.html#GPLRequireSourcePostedPublic
[3] http://www.gnu.org/licenses/gpl-faq.html#CanIUseGPLToolsForNF
[4] http://www.gnu.org/licenses/gpl-faq.html#IfInterpreterIsGPL