Re: GSL within Public Domain Software

[Steve ROBBINS <stever at bic dot mni dot mcgill dot ca>]

On Mon, May 07, 2001 at 05:24:47PM +0100, Jason Beegan wrote:
> 
> > On Sat, 05 May 2001, Peter Hopfgartner wrote:
> > > Basically, linking with a GPL library, means that you should put your
> > > program under a similar license as the GPL, too. You must allow access
> > > to the source.
> > > 
> 
> I think this is a bit misleading.  It depends what you mean by
> similar.  As long as the software is distributed under a free license
> which is compatible with the GPL there is no problem.  Examples of
> compatible licenses include
> 
>        Public domain
> 
>        X11 License
> 	   
>        BSD License (without the advertising clause)
>        The original BSD license (which has an advertising clause)
>        is incompatible.
> 
> I highly recommend that you read
> 
> 	 http://www.gnu.org/philosophy/license-list.html
> 
> for more information on these matters.

I think you're confusing two questions:

1. What licence must I use for a work derived from GPL'd software?
2. What licences are acceptable for *components* included in a work
   derived from GPL'd software?

The page you point to deals with question #2.  I think the original
concern was question #1.  My reading of the GPL, specifically section 2(b),
is that any derived work must be under the GPL.  Not "a similar license
as the GPL", but the GPL full stop.

The GPL can be found at http://www.gnu.org/copyleft/gpl.html.
Section 2(b) is as follows.


  2. You may modify your copy or copies of the Program or any portion of it,
  thus forming a work based on the Program, and copy and distribute such
  modifications or work under the terms of Section 1 above, provided that you
  also meet all of these conditions: 

    a) You must cause the modified files to carry prominent notices stating
    that you changed the files and the date of any change. 

    b) You must cause any work that you distribute or publish, that in
    whole or in part contains or is derived from the Program or any part
    thereof, to be licensed as a whole at no charge to all third parties under
    the terms of this License. 


 -S