Licensing help (in general)?

[Anthony11]

I've read the SFML license which says that providing the zlib license text file is unnecessary, but preferred. So that got me wondering how can I know, in general, when should I provide the license for any library, not just the SFML one. Hypothetically speaking, if I created a EXE program which includes a library either static or dynamic, how can I know whether I'm obligated to include the their's respective license file in my final software. All the licensing seem counter-intuitive for me, for example, Lua states that the license must be provided in every distribution, and MTA:SA (which uses it) doesn't provide it's license. I know this may be 'a little off topic for this forum', but I didn't know where else to ask it (can't register on CB forum for some reason), but when I release my software, I don't want to deal with any legal trouble (ofc). So does anyone have any experience with this?

[eXpl0it3r]

Well you know by reading and understanding the license text.

If something doesn't provide a license you're usually better off not using said piece of software at all, or ask the author to provide one. Because if there's no license, the author can pick one at any time and you might be forced to use a different library.

In general if you want to be sure, you'll have to hire a lawyer that can tell you exactly what you can or can't do with a given license. Legal advice on any forum or website is usually not reliable.
Personally I often look up an unknown license on TLDRLegal.

[Anthony11]

thanks, that website was exactly the thing what i was looking for (subconsiously) , it's no doubt that it i'll help me, especially since i'm bad with understanding legal stuff

[Nexus]

When in doubt, contact the library developers and ask them about your specific situation. They know better than anyone else how they want their license to be applied.

(Of course the license text is binding, and the base for legal cases. I'm referring to things that are not explicitly covered. And it's very unlikely that somebody sues you despite allowing you a certain action.)

[Brax]

When you say "licensing the code" does that practically means simply copy-pasting the license text where is necessary ( and obliging yourself to it) or are there other things involved (say, paying royalties to the creator of the license) ? 

I am sorry, but I really do not understand how all that licensing thing works, and the more I search, the more I get confused. 

[Jesper Juhl]

Maybe this way of thinking about it will help:

When somebody creates a work (say a library) then, by default, you have no right to use it in any way.
The licence is a document with a set of terms and conditions the author requires you to adhere to in order for you to gain certain rights to use the work. Exactly what those terms are and what rights you are granted depends entirely on the text of the license.

Some licenses require nothing of you and grant you every right imaginable.
Some require you to publish the licence along with your work.
Some require you to release any modifications (if any) to the licensed work.
Some require you to release the source of your own code.
Some require you to pay a licencing fee.
Etc.

The rights you are granted (if you adhere to the terms) also vary.
Some licences allow you to do whatever you like with no restrictions.
Some allow you to access and modify the source.
Some just allow you to use a specific binary.
Some allow you to share modifications and some don't.
Etc.

In any case, the license is what the author has chosen to require of you in order to allow you some use of their work and is the only thing that allows you to use it at all. But, the only way to know specificaly what you need to do and what rights you are granted in return is to read the text of the specific license in question.
And of course you always have the option of just not using the work if the license disagrees with you

Note that I am not a lawyer, nor do I play one on TV. For proper legal advice contact a real lawyer 

[shadowmouse]

So if you make something (let's keep the example of a library), can you put anything you want in the license, or is it a better idea to find a pre-existing license and post a link to that? I mean, if you put something really stupid in the license and put a notice by the download button saying you must adhere to the license if you download the software, is it legally binding?

[Nexus]

So if you make something [...], can you put anything you want in the license, or is it a better idea to find a pre-existing license and post a link to that?

You can put whatever you like. However, since you're probably not a lawyer, it's safer to rely on existing licenses with a wording that is proven to be applicable in the real world.

[Jesper Juhl]

Or, at the very least, get a lawyer to review your homebrew license before use if you want to actually stand a chance of enforcing it.

[eXpl0it3r]

I mean, if you put something really stupid in the license and put a notice by the download button saying you must adhere to the license if you download the software, is it legally binding?

Yes and no. You can do it, but if it's obviously misleading it won't be legally binding. E.g. you can't say it's free but have in the 10th paragraph a notice that after a day you'll have to pay $100.

[shadowmouse]

Thanks for all the quick replies! I wasn't sure but I remembered things like that happening in the past (I think Game once said you officially agree to join the horsemen of the apocalypse if you buy from them or something like that) and I wasn't sure how these things actually worked.

[dabbertorres]

I've found Github's choosealicense.com and this flowchart useful in the past.

[Brax]

The replies were really helpful, thanks!

[SeriousITGuy]

Thanks for the link, dabbertorres. Didn't know about that, looks interesting. OSS Licensing is a jungle, and this definitly helps.

I also want to add a special case, which might be interesting for some of us Germans. In Germany there is no way to opt out of copyright and mind property. So as a German, writing code in Germany, you cannot legally release it to public domain (CC0) because German law does not allow that. So Unlicense and stuff does not work in Germany. So if you are German, it's best to always provide a license which takes you out of liability for your works, because it is always your property. So take at least zlib or MIT License.