[Tutor] Borrowing free code

[Steven D'Aprano]

On Tue, Dec 04, 2018 at 11:43:05PM +0000, Alan Gauld via Tutor wrote:
> On 04/12/2018 19:31, Avi Gross wrote:
> 
> > But some packages are simply python code that you can 
> > simply insert into your own python files. 
> 
> If they are fully public domain that's probably true.

Almost nothing younger than 70 years is in the public domain. Nearly all 
countries share certain copyright laws, including automatic granting of 
copyright for the life of the author + many years (exactly how many 
depends on the country) whether you want it or not.

According the lawyers behind the Creative Commons, many jurisdictions 
make it difficult if not impossible to voluntarily give up copyright and 
put a work in the public domain:

https://creativecommons.org/share-your-work/public-domain/cc0/

One of the few exceptions is that many (but not all) works by the US 
government are required to be placed in the public domain by law.

Having said that, all is not *quite* lost (yet). There are still ways to 
get equivalent freedom as if the work was in the public domain, and 
another Mickey Mouse Copyright Extension Act is unlikely to occur any 
time soon.


> If they are copyright (even if open/free) you would be
> potentially liable for prosecution since you are copying
> someone else's work.

That's a rather negative way of looking at it.

Copyright infringement is typically handled through the civil courts: 
the legal authorities don't press charges for copying (except, perhaps, 
in the case of large-scale piracy of manufactured goods like fake 
designer handbags, movie DVDs, etc). Rather, the copyright owner has to 
sue you. If the copyright owner is explicitly giving you the right to 
copy and modify the software, which is the case for FOSS (Free Open 
Source Software), then you have nothing to fear so long as you have a 
valid licence.

If you have a valid licence to use and copy the software, and you obey 
the licence terms, then you are in no danger of being prosecuted for 
copyright infringement because you are licenced to do so.


> Even if it is open source then at the very least
> you should include a comment to the effect that
> the code is based on, say, M Palin's file parrot.py
> or whatever.

Giving credit might be good from an ethical point of view, but it may 
not be either necessary or sufficient (depending on the licence).

Some examples: 

The MIT and BSD licences do not explicitly require you to credit the 
author, but they do require you to include a copy of the original 
author's copyright and licence in your work:

https://en.wikipedia.org/wiki/BSD_licenses
https://en.wikipedia.org/wiki/MIT_License

If you choose to give credit as a courtesy, that's fine, but you must be 
careful as to do so in such a way that you avoid giving the impression 
that the author endorses or is responsible for your work.

    Good: "MyApp, by me, with a big thank you to J. Cleese for 
    his spam library."

    Bad: "MyApp with spam by J. Cleese!"


On the other hand, the GPL requires more than just credit, it requires 
that (with some exceptions, including fair use) if you duplicate their 
code, that your code in turn must be released under the GPL as well. 
Merely giving credit is in no way sufficient.

And on the gripping hand, you have ultra-permissive public-domain like 
licences such as the creative commons CC0 or the Toybox licence:

https://en.wikipedia.org/wiki/Public-domain-equivalent_license

neither of which require credit be given.

Regardless of the licence, you must obey the conditions (whether they 
are minimal, as in the MIT licence, or onerous and difficult as in most 
proprietary licences) in order to be legally permitted to copy the work. 
But if you have a licence to copy, then of course you may copy according 
to the terms of the licence.

In a practical sense, copying trivial amounts of code from software 
licenced under the MIT licence, or similar, would be highly unlikely to 
get you sued. For starters, the author would have to know you copied it, 
and care, and track you down in real life, and sue you. And if the code 
snippet was small enough, you could defend on the basis of fair use.

(Although more and more jurisdictions are taking a hard-line, minimalist 
approach to fair use, allowing it effectively only for the purposes of 
satire. Or even not acknowledging a fair use right at all.)

Another factor may be that, regardless of the *actual* legal risk, some 
employers may not allow copying or use of (some or all) FOSS software 
even if licenced, because they may fear the unknown, or they believe 
anti-GPL propoganda ("its a virus that means you will have to give up 
your intellectual property"), ethical reasons (copying without 
attribution may be plagiarism), or possibly even for legitimate legal 
reasons ("the GPL is not compatible with our licence").

Bottom line: yes, you can legally copy FOSS software, under certain 
conditions, and need not fear being prosecuted.

(Actually, you could even copy closed-source proprietary software, if 
you have a licence allowing you to do so.)


-- 
Steve