DEP-5: binary package affected by license $foo

[Frank Lin PIAT <fpiat@klabs.be>]

Hello,

As I was updating the copyright file in a package, I wondered if it
would be useful to add an optional header (named "Binary-Package" or
whatever), to state which binary package is using that file and license.

The rational is that sooner or later, we will want to use the
machine-interpretable copyright file to validate packages freeness,
license compatibilities and so on.

Some sample scenario:

Exemple 1:
> File: doc/info/*
> License: GFDL-NON-FREE
> Binary-Package: none
The package contains a file covered by a not-so-free license, but
that file isn't used to build the binary file. And the file isn't
shipped in the binary files.


Exemple 2:
> File: foo.c
> License: GPL-2
> Binary-Package: foo 
> 
> File: bar.c
> License: GPL-3
> Binary-Package: bar 
The source package contains some files covered by two incompatible
license, but it isn't a problem because the binary aren't combined at
build nor at link time (or example).

Exemple 2:
> File: foo.c
> License: GPL-2
> Binary-Package: foo 
> 
> File: doc/info/*
> License: GFDL-NON-FREE
> Binary-Package: foo-doc-is-non-free
The source package produces both a free and non-free package.


This extra header would be completely optional, and only useful to
white-list some specific situation.

That's just an idea (a foolish idea?)

Franklin