Does a GPL API infect its apps?

[John Cowan]

Ken Arromdee scripsit:

> The GPL says that my added function must be GPL when it is distributed as part
> of a GPL program.  Once it becomes GPL, it stays GPL--the GPL doesn't contain
> any clause saying that the function once again becomes non-GPL after it is
> removed from the program.
> 
> This causes the virus effect, since the other person who is using my function
> must place their code under GPL.  They would have to go directly to me in order
> to get a non-GPL copy of the function, even though that copy is byte-for-byte
> the same as the copy they snarfed from the program.

Or you could publish your change under a dual license, like GPL + BSD/MIT.
Then they could apply the less restrictive license and use the code
as specified.

In effect, the LGPL does this, since anything licensed under the LGPL
is dual-licensed under the GPL.

> Here's a hypothetical version which does not have this problem:
> 
> >But when you
> >distribute the same sections as part of a whole which is a work based
> >on the Program, the distribution of the whole must be on the terms of
> >this License or a license which grants permissions which are identical to this
> >License except for the possible addition of extra permissions on the sections
> >which are identifiable works as described above.

This is already possible, since a distribution of the PART is not a
distribution of the WHOLE.

-- 
John Cowan                                   cowan at ccil.org
       I am a member of a civilization. --David Brin