RE: [Boost-users] Re: about license

From: Darryl Green (Darryl.Green_at_[hidden])
Date: 2004-02-25 23:56:16

Cross posted from boost-users...

> -----Original Message-----
> From: David Abrahams [mailto:dave_at_[hidden]] 
> Sent: Wednesday, 25 February 2004 11:43 AM
> Marleny Rafferty <marleny_at_[hidden]> writes:
> 
> > Hi-
> >
> > I am considering using boost in my applications, but I have 
> a question
> > about the boost license at 
> http://www.boost.org/LICENSE_1_0.txt .  It
> > says (edited) 
> "Permission is hereby granted, free of charge, to ...
> > use [and] reproduce ... the Software".
> >
> > It also says that any derivative works must also have the 
> same license
> > grant.
> >
> > If my application uses boost libraries unchanged, is it considered a
> > derivative work?
> 
> Yes.

Really? The ligitimacy of this stance seems questionable (but ianal
etc). Further I did not see it as being part of the objectives for the
license. Quite the opposite in fact.

> 
> > If so, does that mean that if I distribute my compiled software, I
> > must allow free of charge use and distribution?
> 
> No, the license gives an explicit exemption for compiled code
> (emphasis mine):

[let me just re-insert some additioanl context here]
! The copyright notices in the Software and this entire statement
! ...
! must be included in all copies of the Software, in whole or in part,
and
> 
> all derivative works of the Software, UNLESS SUCH COPIES OR DERIVATIVE
> WORKS ARE SOLELY IN THE FORM OF MACHINE-EXECUTABLE OBJECT 
> CODE GENERATED BY
> A SOURCE LANGUAGE PROCESSOR.
> 

I took this to mean that nobody can delete/change the copyright/license
in the sources if they copy or produce a derivative work but that there
is no need to include the license in a binary distribution. It did not
occur to me that leaving the license in place somehow forms a viral
attachment to other source in a source distribution.

It potentially makes this license incompatible with the intent of other
(open and closed) source licenses eg.

// some_gpled_source_file.cpp
// this file is distributed under the gpl

// changed some stuff so we use boost libs
#include <some_boost_lib>
// oops - now it is some boost/gpl hybrid??????

I thought avoiding this sort of thing was precisely why the boost
license was developed. I also thought this interpretation of "derived
work" was somewhat contentious anyway.

In a commercial context, this interpretation appears to make this
license hopeless - anyone obtaining a copy of source code which uses
boost (which you appear to be claiming is automatically a derivative
work), appears to be free to do what they like with it. It is hardly
reasonable that this occur if a company distributes source code with
some particular intent/license for its use. That is even without
considering the issue of copies obtained without the company/authors
permission, whether the copy was obtained accidentally or criminally,
and then redistributed. I'm keen to stop people copying my commercial
executables, but I'm a lot more keen to stop them running off with the
source code!

A bit of digging through the archives finds

http://aspn.activestate.com/ASPN/Mail/Message/boost/1686928

Which seems to explain why I thought the intent was what I understood it
to be. Whatever the conclusion I think this needs to be in the FAQ.

Regards
Darryl Green.

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