Python in Process Control?

[Peter L Hansen]

Andrea Griffini wrote:
> The only thing that scares me a bit about using python
> is that industrial control is (at least for the part
> I'm seeing for my job) terribly closed-source.
> I see for example that its very very common to use
> even hardware locks for the software.

That's true, and sadly so.  It's also one of the things
which Cameron and I and others are keen to see change,
and which change we believe would have a significant
and positive impact on the industry in a variety of ways.

Having companies always rewrite their own copy of something
from scratch is a stupid, stupid way to do business, when
their business is not supposed to be writing drivers for
obscure pieces of hardware.

Having those companies wake up and smell the coffee --
which in this case is their competition, companies like
mine, which are accelerating many times over their
productivity by using modern tools and techniques
and by *sharing* non-core stuff -- is one of the goals
we've been talking about here.

> I'm not my boss, and could be hard to explain that it's
> not a problem using an interpreted language that is
> easily decompilable and using modules with licenses
> that are basically nonsense in this context.

This sort of thing is ultimately not an issue with
Python per se, or is only slightly more an issue with
Python than with some other languages.  I've yet to
see a library that couldn't be used in spite of its
supposed hardware or software copy protection.  Better
to try to find reasons for customers to keep paying
you (support, access to improvements) than to worry
that you might have missed some revenue from a few
that are unethical crooks...

> To a very specific question I was answered here that
> the best thing to do before using e.g. pygame in a
> closed source product is consulting a lawyer; and
> that obtaining a clear answer would have been a sign
> that the consulted lawyer isn't a good one.

It's an answer, and in some ways a good one, but in
other ways it passes the buck to someone who is in the
business of telling people what they already know and
fear is true: there are no guarantees, nothing you can
do can actually *prevent* you from getting sued, and
by the way please pay my last invoice for $400/hour...

I'd say the "best thing" to do would be to start by
collecting the various licenses involved and actually
looking them over.  I haven't done that with PyGame,
but unless it includes GPL stuff, there's a decent
chance that there's no real impediment to using it
in a closed source product, except perhaps your guilt
at attempting to profit from the hard work of many
others without even a token attempt to contribute
something back to the community. ;-)

-Peter