Re: Final text of GPL v3 On Mon, Jul 02, 2007 at 06:25:57PM -0400, Anthony Towns wrote:
> >   The "System Libraries" of an executable work include anything, other
> > than the work as a whole, that (a) is included in the normal form of
> > packaging a Major Component, but which is not part of that Major
> > Component, and (b) serves only to enable use of the work with that
> > Major Component, or to implement a Standard Interface for which an
> > implementation is available to the public in source code form.  A
> > "Major Component", in this context, means a major essential component
> > (kernel, window system, and so on) of the specific operating system
> > (if any) on which the executable work runs, or a compiler used to
> > produce the work, or an object code interpreter used to run it.

This was different in draft 2, which said:

] The "System Libraries" of an executable work include every subunit
] such that (a) the identical subunit is normally included as an adjunct
] in the distribution of either a major essential component (kernel,
] window system, and so on) of the specific operating system (if any)
] on which the object code runs, or a compiler used to produce the object
] code, or an object code interpreter used to run it, and (b) the subunit
] (aside from possible incidental extensions) serves only to enable use
] of the work with that system component or compiler or interpreter, or to
] implement a widely used or standard interface for which an implementation
] is available to the public in source code form.

In that, the "subunit" is:
	- something joined to a major essential component of the
	  operating system, but not an essential part of it
        - something that does nothing more than enable use of the work
	  with that component, or implements a widely used or standard interface

Draft 1, in turn, said:

] As a special exception, the Complete Corresponding Source Code need not
] include a particular subunit if (a) the identical subunit is normally
] included as an adjunct in the distribution of either a major essential
] component (kernel, window system, and so on) of the operating system on
] which the executable runs or a compiler used to produce the executable or
] an object code interpreter used to run it, and (b) the subunit (aside from
] possible incidental extensions) serves only to enable use of the work with
] that system component or compiler or interpreter, or to implement a widely
] used or standard interface, the implementation of which requires no patent
] license not already generally available for software under this License.

which again distinguishes things that get an exception from the actual
major essential components of the operating system.

The rationale for this for draft 1 was:

] The final paragraph of section 1 revises the exception to the source
] code distribution requirement in GPLv2 that we have sometimes called
] the system library exception. This exception has been read to prohibit
] certain distribution arrangements that we consider reasonable and have
] not sought to prevent, such as distribution of gcc linked with a non-free
] C library that is included as part of a larger non-free system. This
] is not to say that such non-free libraries are legitimate; rather,
] preventing free software from linking with these libraries would hurt
] free software more than it would hurt proprietary software.
]
] As revised, the exception has two parts. Part (a) rewords the
] GPLv2 exception for clarity but also removes the words ``unless that
] component itself accompanies the executable.'' By itself, (a) would be
] too permissive, allowing distributors to evade their responsibilities
] under the GPL. We have therefore added part (b) to specify when a
] system library that is an adjunct of a major essential operating system
] component, compiler, or interpreter does not trigger the requirement to
] distribute source code. The more low-level the functionality provided
] by the library, the more likely it is to be qualified for this exception.

    -- http://gplv3.fsf.org/gpl-rationale-2006-01-16.html

Sadly the sentence beginning "We have therefore added part (b)
..." doesn't make any more sense to me than the GPLv3 legalese anyway.

Cheers,
aj

