Python programs always open source?

[Ben Finney]

"Diez B. Roggisch" <deets at nospam.web.de> writes:

> Ben Finney schrieb:
> > My claim (and IANAL) is that it doesn't matter *what* license
> > Python is distributed under; unless you do something with Python
> > that is a right of the copyright holder, such as distributing part
> > or all of Python, the copyright license terms of Python have no
> > legal effect on what license you choose for your own work.
>
> Not true for the GPL. Part of python is the library, which you
> either use explicit (I can't imagine a program that doesn't, beyond
> print "hello world"), or implicit (sys and os are AFAIX used
> internally to bootstrap the interpreter)

And just about every program on a GNU/Linux system uses the libc
library, which is distributed under the GPL. That license *only*
affects works that are *derivative* of the libc library.

> And the GPL exactly requires that when a library licensed under it
> is used, that makes the using program GPL-licensed, too.

No, only when a new work *derives from* the existing work does
copyright on the existing work take effect.

You may be thinking of the "linking" clause, which depends on the
*inclusion of* existing header files from the library code, supplied
under the GPL. There's no such concept in an interpreted language like
Python: you write your program in the Python language without
including a single piece of the original in your work.

The GPL itself is clear on the fact that its terms cannot claim
anything that is not granted to the copyright holder -- and
*execution* of a library is not a right over which the library author
has any rights.

Even if execution (or "use") of a program library, without including
*any* of its code in your own work, were a right the library author
could restrict, no free software program can place any restriction on
execution (otherwise it's trivially non-free). If Python's license
were ever to have such a restrictive term, it would likely be
unenforcible, but would certainly disqualify it from inclusion in any
free operating system.

Copyright is currently weighted greatly in favour of copyright
holders, but please don't buy into the absolute-power rhetoric more
than necessary.

-- 
 \       "Yesterday I told a chicken to cross the road. It said, 'What |
  `\                                          for?'"  -- Steven Wright |
_o__)                                                                  |
Ben Finney