[Savannah-hackers-public] Re: [gnu.org #548720] Explanation about permissive licences?

[Karl Berry]

Hi Mario,

(Is some savannah applicant doing this complicated 
multiple-licenses-in-a-file stuff?)

    At what level I should state the copyright holder and licence?, by
    function, by file, by line?.

Well, the basic unit is the file.  As you know, usually each file states
its own copyright information.  In unusual situations (images, etc.),
another file in the same directory or "nearby" might state it.

For a particular file, the only important criteria is to make the
situation clear.  There's no one ironclad rule about how to do it.  That
might mean doing it by function, or by putting markers in the file, like
"everything below here is under the GPL, see above for full notice".
Referring to specific line numbers seems wrong, since they will change
whenever the file is changed.  I would generally recommend putting all
the relevant notices at the top of the file.

There is one (and only one, that I can think of) exception to this: if a
file is under some free software license, and public domain material is
being merged into that file, there is no need to keep the indication of
which parts are public domain.
http://www.gnu.org/prep/maintain/html_node/Copying-from-Other-Packages.html

Of course, the simplest (and best) general approach is to keep each file
under a single license, and if work is done under a different license,
put it in a different file.  That's what we always try to do in GNU.

Best,
Karl