[Asterisk-Dev] asterisk application license

[Kevin P. Fleming]

David Pollak wrote:

> The GPL is very restrictive.  If your code links with GPL code, your 
> code my be GPLed.  Thus, if you write code that links into a running 
> Asterisk instance, you must GPL that code.

Uhh... that's an oversimplification.

You can _write_ anything you want, and you are not bound by any laws or 
licenses to license your own code in any particular fashion. You are 
also not bound by any laws or licenses to distribute your code, if you 
do not wish to. Anything you write and use on your own is completely 
yours to do with as you see fit.

However, if you write code that is _distributed_ (in either source or 
binary form), and that code is intended for, and would only work while, 
being an Asterisk plug-in module, then you must license the source code 
as GPL or LGPL. This is because any such code would be considered a 
"derivative work" of Asterisk, and you obtained Asterisk under a GPL 
license. If you distribute binaries of your code, you must make the 
source available to users of your binaries, and they have the implicit 
permission to redistribute that source as long as they acknowledge where 
they obtained it.

Conversely, if you obtain Asterisk under a non-GPL license (because 
Digium has the right and ability to sell non-GPL licenses if they 
desire), again you can extend it in any fashion you see fit, including 
distributing binary-only copies of your code, and you are not bound by 
the GPL at all.

_This_ is the viral nature of the GPL, and it's a good thing IMO.