Subject: Re: Perl Tk license
From: Karl Fogel <>
Date: Thu, 21 Apr 2011 19:34:41 -0400

Dale <> writes:
>I want to write an application that uses the Perl Tk module and
>license my code under GPL
>It is the license of Perl Tk that buffles me :
>At the module's site
>it says :
>"The distribution is licensed under a license that is not approved by
> but that allows distribution without restrictions "
>then inside it says :
>"# This program is free software; you can redistribute it and/or
># modify it under the same terms as Perl itself, subject
># to additional disclaimer in Tk/license.terms due to partial
># derivation from Tk8.0 sources."
>and then in the Tk/license.terms says :
>"The authors hereby grant permission to use, copy, modify, distribute,
>and license this software and its documentation for any purpose,
>that existing copyright notices are retained in all copies and that
>notice is included verbatim in any distributions. No written
>license, or royalty fee is required for any of the authorized uses.
>Modifications to this software may be copyrighted by their authors
>and need not follow the licensing terms described here, provided that
>the new terms are clearly indicated on the first page of each file
>they apply."
>What does that actually mean? where should I put those terms? 
>inside my application's source code distribution should I also include
>Tk module's source code ?

I am not a lawyer, but I see no reason why you can't license your (new)
code under the GPL, and have it depend on the Tk module, which you may
distribute along with your code if you choose.

In general, we don't have the resources to provide free legal help, but
we try to give easy & quick answers where we can.  I hope this helps.