Base Perl modules with BSD software

[Philippe Verdy]

Matthew Flaschen wrote:
> Alex wrote:
> I believe most of the modules included in Perl use Artistic/GPL.
> Artistic is explicitly not a copyleft license, and says, "The scripts
> and library files supplied as input to or produced as output from the
> programs of this Package do not automatically fall under the copyright
> of this Package, but belong to whomever generated them, and may be sold
> commercially, and may be aggregated with this Package."  That means if
> you only use Perl/Artistic modules you shouldn't have to be under the GPL.

Look into the GPL, and you'll see that it does not automatically assigns the
GPL licence to the data that is fed into or produced by the GPL program, if
this data itself is not licenced by the GPL, and if the output does not
contain significant parts of data that can be derived directly from the GPL
program alone, but only from the data provided by the user of the program
and not by the GPL copyright holder.

Users can then use GPL programs with their own private data, and
redistribute the result produced without being bound to the GPL licence.

Otherwise, you could not even legally play a copyrighted music file using a
GPL-licenced media player...

You could not browse most of the web (implicitly copyrighted even if there's
no explicit licence or licencing terms saying it) with a GPL-licenced
browser.

You could not use a GPL-covered document processor to print a copyrighted
book.

You could not publish copyrighted research papers using a GPL-covered TeX
processor.

You could not publish a copyrighted web site using a GPL-covered web server.

You could not download a copyrighted file using a GPL-covered FTP client...

(and all this is independent of the type of licence that covers the input
data: the copyright on this data is not automatically reassigned, its
licence is not altered in the output, unless the output is a derived work
covered by the GPL of the program with the help of which you have generated
it.)