[Flug] Violazione della licenza GPL?

[Francesco Poli]

On 2002.05.25 14:38:33 +0200 ^SHIVA^ wrote:
[...]
> Non tutte le distro sono totalmente GPL...vedi caldera (che ha
> "comprato" 
> sco-unix) e piu' recentemente suse che sembra volersi spostarre su una
> 
> politica piu' commerciale.

Prima di tutto distinguiamo: commerciale non significa proprietario e
viceversa.
L'opposto di libero e` proprietario.
L'opposto di commerciale e`... non commerciale!  ;)

Sono possibili tutti e quattro i casi:

* software libero non commerciale (ad esempio la distribuzione Debian
GNU/Linux)
* software libero commerciale (ad esempio la distribuzione RedHat Linux)
* software proprietario non commerciale (ad esempio un programma
freeware come Powerarchiver)
* software proprietario commerciale (ad esempio Microsoft Office XP)

Il fatto che una distribuzione di software sia composta da programmi GPL
assieme a programmi proprietari e` consentito dalla licenza GPL stessa:

"mere aggregation of another work not based on the Program
with the Program (or with a work based on the Program) on a volume of
a storage or distribution medium does not bring the other work under
the scope of this License"

Tuttavia i sorgenti dei programmi GPL (che siano distribuiti da soli o
insieme ad altri programmi di qualsivoglia genere) *devono* essere
disponibili 

  "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,

    b) Accompany it with a written offer, valid for at least three
    years, to give any third party, for a charge no more than your
    cost of physically performing source distribution, a complete
    machine-readable copy of the corresponding source code, to be
    distributed under the terms of Sections 1 and 2 above on a medium
    customarily used for software interchange; or,

    c) Accompany it with the information you received as to the offer
    to distribute corresponding source code.  (This alternative is
    allowed only for noncommercial distribution and only if you
    received the program in object code or executable form with such
    an offer, in accord with Subsection b above.)"

Quindi, commerciale o non commerciale, assieme ad altro software
(eventualmente proprietario) oppure no, non c'e` cristi (there's no
christ...): il codice sorgente di un software GPL deve essere
distribuito o comunque disponibile. Altrimenti si viola la licenza e non
si ha piu` il diritto di modificare o ridistribuire il software stesso:

  "4. You may not copy, modify, sublicense, or distribute the Program
except as expressly provided under this License.  Any attempt
otherwise to copy, modify, sublicense or distribute the Program is
void, and will automatically terminate your rights under this License.
However, parties who have received copies, or rights, from you under
this License will not have their licenses terminated so long as such
parties remain in full compliance.

  5. You are not required to accept this License, since you have not
signed it.  However, nothing else grants you permission to modify or
distribute the Program or its derivative works.  These actions are
prohibited by law if you do not accept this License.  Therefore, by
modifying or distributing the Program (or any work based on the
Program), you indicate your acceptance of this License to do so, and
all its terms and conditions for copying, distributing or modifying
the Program or works based on it."

-- 
      Francesco Poli   <frx@firenze.linux.it>
===================================================
 "May the Source be with you!"  -- Eric S. Raymond