Re: [Firebird-devel] Warning: readline is GPL - incompatible with
Nick Phillips wrote:
> On Thu, Aug 08, 2002 at 08:00:43AM -0600, Joe Moore wrote:
>> Section 1 of the GPL grants permission to "copy and distribute
>> verbatim copies".
>> Section 2 grants permission to "modify [...], and copy, and
>> distribute". Section 3 grants permission to "copy and distribute" in
>> binary form. Section 4 forbids all other ways to "copy, modify,
>> sublicense, or distribute".
>> Nowhere in the GPL is permission to "modify without distribution".
>> The user wants to build an improved version of FireBird, but not
>> distribute the results. Does the GPL allow them to link GNU Readline
>> with FireBird (but not changing any other aspect of the source) for
>> their own use?
> Of course it does. Nowhere is the user in question modifying readline,
> or doing anything other than using it in the normal manner.
> You seem to be confusing use of readline with modification of firebird.
> After being built with readline, the firebird binary does contain bits
> of readline. This is relevant only when considering whether and how you
> might distribute that resulting binary.
The user has modified neither. The user simply set an environment variable
at build-time (MAKEFLAGS=-lreadline).
The resultant executable is a _derived work_ (as I understand copyright law)
of BOTH GNU Readline and FireBird. It is clear from the GPL (and the GPL
FAQ) that the result can not be distributed. But can it even be built?