Re: Licensing of Octave Scripts

[Jaroslav Hajek]

On Sat, Feb 6, 2010 at 12:22 AM, Trevor Law <address@hidden> wrote:
> Hello,
>
> My name is Trevor Law and I'm looking to find out whether or not
> Octave scripts that I might share must be released under the GPL.
> Although I don't need them to be proprietary, the GPL is confusing for
> a non-lawyer, and seems to require that I post the Octave source code
> along with any script I post online, which seems unnecessarily
> cumbersome.
>
> On the Octave license page it is stated:
> "Although enhancements to Octave that are written as function files in
> Octave's scripting language are not required to be redistributed under
> the terms of the GPL, we encourage you to release your enhancements to
> Octave under the same terms for the benefit of all users."
>
> http://www.gnu.org/software/octave/license.html
>
> However the FSF GPL FAQ
> (http://www.gnu.org/licenses/gpl-faq.html#WhatCaseIsOutputGPL)
> suggests otherwise.  (The faq entry is slightly long so I did not
> paste it).


Eh. You probably meant this:
http://www.gnu.org/licenses/gpl-faq.html#IfInterpreterIsGPL

> Essentially the answer says that if the interpreter
> provides bindings to GPL code then programs written for it must be
> GPL'd.  The Octave source is GPL'd, and I imagine it probably uses
> several GPL'd libraries (perhaps GSL?), which suggests I need to GPL
> anything I post anywhere.
>
> Any clarification you could provide would be much appreciated.
>

Basically, your reasoning is logical, but you misinterpret the word
"bindings". "Bindings" in a language X to a library Y means a
non-standard set of functions, classes etc. to exploit the
capabilities of that library. If the library is just used to implement
some part of the interpreter, that's not bindings.

For example, if Octave used GSL to implement the erf function (it
doesn't, but we thought about it), it doesn't mean your program needs
to be GPL'ed if it uses erf. On the other hand, if you install the GSL
package and use erf_gsl (presumably because you discover a defect of
the built-in erf), then your program needs to be GPL'ed.

I think the only function in core Octave that can be regarded as
bindings is glpk. So, if you use glpk in your script, it should
probably be GPLed. But I'm not sure, so I'd like to hear others'
opinions.

-- 
RNDr. Jaroslav Hajek, PhD
computing expert & GNU Octave developer
Aeronautical Research and Test Institute (VZLU)
Prague, Czech Republic
url: www.highegg.matfyz.cz