[SGVLUG] GPL and CPL

Terry Hancock hancock at anansispaceworks.com
Fri Apr 27 21:26:57 PDT 2007


Emerson, Tom (*IC) wrote:
>>"Laszlo Systems chose the CPL because it [...]
>>permit[s] proprietary applications written using OpenLaszlo 
>>to remain proprietary, but ensures that any contributions to 
>>the OpenLaszlo platform itself remain open source and are 
>>"given back" to the open source community."
> 
> They could still use the GPL for that -- after all, consider the
> compiler (gcc)  the GPL maintains a similar attitude about the
> distinction between products made BY a GPL program vs. enhancements TO a
> GPL program (and/or variations OF the GPL'd product)

This may or may not be true depending on design details. If the product
of compilation includes part of the GPL'd work, then it is affected by
the copyleft. This is the reason why certain important libraries use the
LGPL license.

> Or to put it another way, the GPL does not extend to the OUTPUT of a GPL
> program.

There are quite a few fence-sitting cases on that point, IIRC.

> As to the rest of the CPL, I have a longer thought on it I started last
> night (but fell asleep before hitting "send"), but the long and short of
> it is, "this just sounds weird..."

I've reviewed it before, and I believe that by and large, the CPL is
very very similar to the LGPL in effect. It's main distinctions:

* Differences in how patents are handled (the CPL is particularly clear
on avoiding liabilities for patent infringement)

* No GNU/FSF branding or preamble (there are people who consider this a
big plus)

* I believe the warranty disclaimer is slightly different

* There is a jurisdictional requirement (New York)

It has been reviewed and is considered "Free" by Debian, FSF, and OSI.
It is, like most alternative copyleft licenses, incompatible with the
GPL (there is no explicit right to convert to the GPL, which would be
the only way to effect that compatibility).

All in all, it's not my favorite license (I personally consider
GPL-compatibility to be very important), but it is a free/open-source
license.

But, IANAL/TINLA, of course.

Cheers,
Terry

-- 
Terry Hancock (hancock at AnansiSpaceworks.com)
Anansi Spaceworks http://www.AnansiSpaceworks.com



More information about the SGVLUG mailing list