[I18n-sig] Codec licenses

M.-A. Lemburg mal@lemburg.com
Fri, 26 Jan 2001 18:19:08 +0100

Tamito KAJIYAMA wrote:
> M.-A. Lemburg wrote:
> |
> | > scanning through the CVS archive of the SourceForge python-codecs
> | > project I found that most codec packages were placed under the GPL
> | > for some reason. This makes the codecs unusable for software which
> | > isn't GPL compatible and limits its usefulness considerably.
> | >
> | > Please consider either moving to the LGPL which does not have the
> | > GPL problems (other software relying on it will need to be shipped
> | > under the GPL too), but still assures that your code remains freely
> | > available or one of the Python licenses (preferrably the
> | > old CWI one).
> Well, I have two (opposite?) thoughts regarding to the licensing
> of the JapaneseCodecs package.
> First, I've released the package under the terms of GNU GPL,
> because that license is comfortable for me.  I want users to
> "use" the package in the GNU GPL sense.
> On the other hand, I hope that many people use my software.  If
> needed, I release JapaneseCodecs or its part under different
> licensing terms.  It is not a problem for me that a package that
> includes JapaneseCodecs as its part is released under an open
> source license (like the PyXML package).
> To tell the truth, JapaneseCodecs is the first free software
> package that I've released, and when I released it I was not
> sure what was the best licensing terms for the package.  I've
> chosen the GNU GPL, but the situation seems complex...
> If possible, I'd like to utilize two different licenses: the
> GNU GPL for JapaneseCodecs as a separate package, and another
> license for the composite package that includes JapaneseCodecs
> as its part.
> Hmm...  Does this reply make sense?  I'm confused...

I know its confusing and I am pretty sure that many programmers
out there who put their software under the GPL don't know about
the consequences of this step.

To make it simple:

* the GPL allows your software to be used stand-alone or
  as part of another package which then has to have a license
  compatible with the GPL (many popular licenses out there are
  *not* compatible with the GPL so this causes problems, e.g.
  Zope's license is not GPL compatible, so GPLed modules cannot
  be shipped together with Zope licensed packages)

* the LGPL (Library GPL) does not impose any restriction with
  respect to including it in some package except that the packager
  will have to make the source code of the LGPLed available (possibly
  as seperate package); as a result there are no problems with
  non-GPL compatible products and your software gets used by
  many more people out there

Both versions make sure that your software and any modifications
applied to it are again published under the same terms, meaning
that the source code (including any modification) must be made
available without fee.

GPL is fine for stand-alone products. LGPL should be used for
everything which smells like a library ;) Even better are the
new BSD licenses, since they give your users all the freedom in the

Hope this clarifies things a bit.

Marc-Andre Lemburg
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