licensing: GPLv2, v3, and Apache

[John Gilmore]

> > about the *technical* reasons and differences.

> Apache or GPLv2 is fine. Anything that is GPL-compatable will be acceptable.

Gnash is GPLv3, and it's on the OLPC.  The latest versions of many
other GNU programs are GPLv3 too, and will also make it into later
OLPC releases as it gets rebased on later Fedora releases.

Most "GPLv2" licensed software actually says "GPLv2 or any later
version".  This allows such software to be linked with, and/or
converted to, later versions of the license.  The Linux kernel is one
of the few GPL programs that has stuck with GPLv2-only -- and it
will probably not stay that way for the next hundred years.

I negotiated with a lot of companies as co-founder of Cygnus, which
develops and supports free software for companies that use it.  (It's
now part of Red Hat.)  Licensing your code under Apache, GPLv2,
GPLv2+, or GPLv3+ protects the "Four Freedoms" of its users and
developers; see http://www.gnu.org/philosophy/free-sw.html .  The
practical difference is that later, people who modify GPL software
can't take it proprietary.

Often companies will improve free software, for their own use and the
use of their customers.  The GPL is the argument that makes their
lawyers and managers let go of the improvements, rather than
reflexively making them proprietary because that's what they learned
in law school.  See http://www.gnu.org/philosophy/pragmatic.html .
Cygnus argued to every customer that freeing their changes is a good
business practice, reduces later maintenance costs, reduces market
fragmentation, etc.  But "The license on the underlying software
*requires* it" is the argument that carried the day every time.

Any version of the GPL will do; I use the latest (and allow my
software to be relicensed to later versions) because it's the best.
GPLv3 isn't US-centric; it allows linking with software licensed under
similar non-GNU licenses; and it disallows DRM that would prevent
users from removing restrictions that somebody has inserted in it.
(While DRM on music has started falling out of the market this year,
it's still alive and kicking on proprietary software, video, digital
television, and anywhere else that a monopoly wants control over its
competitors and its customers.)

You can never tell where your software will end up.  I wrote the code
that became GNU Tar, which now exists in every system that uses rpms
or debs, including the OLPC.  I am happy that it's been GPL since 1988,
and is now GPLv3+.

	John