Subj : Re: GPL and using many licences
To   : comp.programming
From : Tatu Portin
Date : Sat Oct 01 2005 01:11 pm

Piotr 'Qertoip' Włodarek wrote:
> I want to use library licensed under GPL. Therefore I have to publish my
> source code under GPL as well. 

No, you don't. But, the license you wish to use must be 
GPL-compatible. [1]

> May I, in addition, publish my source code under other license, i.e. MIT?

Yes, if the license is GPL compatible.

> Of course I've got GPL license text, but I want to know your opinion, since
> there are many misuderstoods in this subject.

Yes, there are. One common is that you should give away source of 
GPL'd app for free.

But if you give the source with the app when you sell it, then you are 
not obliged to provide any public access to the source code. [2]

So, you may sell your app, e.g. for 5000$, providing the source with 
it, and the customer then decides if he/she wants to share his/her 
5000$ piece of software with his/her friends.



[1]:
http://www.gnu.org/philosophy/license-list.html

[2]:

"One of the following", i.e. not all of them.

 >>3. You may copy and distribute the Program (or a work based on it, 
under Section 2) in object code or executable form under the terms of 
Sections 1 and 2 above provided that you also do *one of the following*:

a) Accompany it with the complete corresponding machine-readable 
source code, which must be distributed under the terms of Sections 1 
and 2 above on a medium customarily used for software interchange; or,>>
http://www.gnu.org/copyleft/gpl.html

.