Let's say I want to make a libre alternative to an existing proprietary piece of software. And this proprietary piece of software has its source code publically available, it's just under a non-free license. Can I look at its source code and mimic the its functionality, writing it so it would "look different" or in a different language without being sued later?
Usage of Someone Else's Code
I vaguely remember that pic, whatever came about that whole mess, I don't remember the names.
I know, but how can one prove that I indeed looked at the source code and not just re-implemented the whole thing from scratch?
Same way you investigate almost anything else. For example, is there an exact duplicate of 30 lines of non trivial code? If so, probably copied.
No. This is why clean-room design was invented.
They don't have to "prove" it in a mathematical or philosophical sense, or have footage of you looking at the proprietary code. They only have to convince a jury. And unless you can afford a legal team that's at least as good as theirs, they will.
Thanks for the answer.
I heard about the clean room design but do you have some sources to read about the techniques?
"The term implies that the design team works in an environment that is "clean" or demonstrably uncontaminated by any knowledge of the proprietary techniques used by the competitor.
Typically, a clean-room design is done by having someone examine the system to be reimplemented and having this person write a specification. This specification is then reviewed by a lawyer to ensure that no copyrighted material is included. The specification is then implemented by a team with no connection to the original examiners."
this doesn't stop half of google's app store, but I wouldn't even look at the code. look at what it does at a top level and then re-implement it. I wouldn't even look at the design once you start.
Well, I think you could. After all, isn't the case of what happened with UNIX and GNU/Linux and *BSD?
You're not supposed to, but it's an open secret that both ReactOS and Wine do this with the leaked Win2000 source code. As long as they can't prove anything, you're good.
Its gonna matter once either of those projects become non trivial. Barely any of those matter so microsoft does not give a shit. If they had millions of users they would. You can get away with almost anything when small, just outright copy in most cases except for nintendo IP.
Why won't it also happen with your meme-room design?
GNU specifically did everything in a different way, to the point where looking at the original can't have helped much. There are instructions in the GNU coding standards to try and optimize for different things than the original, for example speed if the original aimed for low memory use.
Stallman had experience duplicating features of Symbolics. At some point he started looking only at the changelog, not the source code, so he didn't have to worry about doing it differently.
No. No. No. Neither ReactOS nor Wine developers spend time looking at proprietary Windows source code.
It might. It's just if your project clearly states that it's clear-room from the start then you can hope that they won't sue you in the first place.
So what stops you from stating that but looking at the code on weekends from your anonymous spare laptop with TAILS et al. which you buried in your friend's village backyard?
Basically nothing. The problem is that you don't even have to actually look at the proprietary source code to get sued for doing so.
so why bother with clean room?
if looking only saves some time, and doesn't make you safer.
Worked for GNU, Wine and ReactOS so it's better than nothing.
not OP, but there were credible accusations a few years ago that ReactOS was doing something like that. I think it was decompilation, though.
Don't even look at the source code. You risk copyright infringement.
If it's not MIT licensed it's toxic cancer and you shouldn't touch it.
They could look at some code and never tell anyone about it
Not at all. The accusations came from an anonymous 4chan shitposter who "trolled" the ReactOS IRC channel with the accusation that their code was "stolen" from Windows. I know this because I was a member of the IRC channel when this happened and also the exact 4chan thread where this shitposter confessed to the anonymous programmers on 4chan. It was this act of shit posting that caused the ReactOS audit and the outcome of the audit proved that there was no evidence to substantiate the accusation of copyright infringement of Windows source code.