6 ms·

Could someone who understands these licenses ELI5?

jacquesm 3y ago
Improved interop with other open source programs because they used to have a 'one off' license. That makes using ZeroMQ harder than it should be because there is always the question of whether or not their license is more or less permissive than the one that you've picked for your project and risks future unintended side effects. This move should lay that all to rest.
- bluGill 3y ago
  Lawyers have mostly looked at the common open source licenses long enough to know what they say: what is compatible with each other, what is compatible with their [corporate/clients] other needs, and otherwise how it works. While mostly they have not been tested in court, there general consensus they will hold up somehow (nobody knows for sure and there are a couple hundred countries that could each decide their own thing). When you do your own license though lawyers need to figure everything out for just your project.
brylie 3y ago
TLDR LGPL3: https://www.tldrlegal.com/license/gnu-lesser-general-public-license-v3-lgpl-3 https://www.tldrlegal.com/license/gnu-lesser-general-public-... TLDR MPL v2: https://www.tldrlegal.com/license/mozilla-public-license-2-0-mpl-2 https://www.tldrlegal.com/license/mozilla-public-license-2-0...
CJefferson 3y ago
The main difference is the LGPL works at the “library” level, and requires the source for the library is open source. It requires in particular you can replace the library, which means you can’t really static link to it from a closed source program (or open source but LGPL incompatible license). MPL works on the “source file” level. You have to release any changes you make to MPL licensed files, but you can link those files into a closed source program any way you like.
- mrweasel 3y ago
  So I could compile a program, dynamically link an LGPL library and that's fine, but the moment I statically link the same program I'd be violating the LGPL. I never considered that, don't that make the LGPL a pretty poor license for pretty much anything?
  - michaelsbradley 3y ago
    You can link statically, see my reply to parent.
    - phkahler 3y ago
      >> You can link statically, see my reply to parent. You can static link code under the equivalent version of GPL license. The point of the LGPL was to compromise so non-free software could still use free libraries. I was unaware of the static compilation aspect of MPL - that's interesting.
      - deleted 3y ago
        [deleted]
      - michaelsbradley 3y ago
        You can statically link closed/proprietary software with LGPLed code, its just a too common misunderstanding that you can’t do so.
      - dartos 3y ago
        I think the other commenter is wrong. You are restricted from statically linking LGPL code in non free programs unless you follow the restrictions in section 4d of the license
  - tom_ 3y ago
    Not necessarily, because it means LGPL libraries are suitable for use with non-free programs. As the library user, this is good, because you potentially get access to free libraries that you'd otherwise be unable to use. (GPL libraries are off limits for non-free programs.) As the library author, this is also good, because your potential user base is widened, but your library can remain free software. (Of course, you could equally spin it that these are bad things - an exercise for the reader.)

Improved interop with other open source programs because they used to have a 'one off' license. That makes using ZeroMQ harder than it should be because there is always the question of whether or not their license is more or less permissive than the one that you've picked for your project and risks future unintended side effects. This move should lay that all to rest.

bluGill 3y ago
Lawyers have mostly looked at the common open source licenses long enough to know what they say: what is compatible with each other, what is compatible with their [corporate/clients] other needs, and otherwise how it works. While mostly they have not been tested in court, there general consensus they will hold up somehow (nobody knows for sure and there are a couple hundred countries that could each decide their own thing). When you do your own license though lawyers need to figure everything out for just your project.

brylie 3y ago

TLDR LGPL3: https://www.tldrlegal.com/license/gnu-lesser-general-public-license-v3-lgpl-3 https://www.tldrlegal.com/license/gnu-lesser-general-public-... TLDR MPL v2: https://www.tldrlegal.com/license/mozilla-public-license-2-0-mpl-2 https://www.tldrlegal.com/license/mozilla-public-license-2-0...

CJefferson 3y ago

The main difference is the LGPL works at the “library” level, and requires the source for the library is open source. It requires in particular you can replace the library, which means you can’t really static link to it from a closed source program (or open source but LGPL incompatible license). MPL works on the “source file” level. You have to release any changes you make to MPL licensed files, but you can link those files into a closed source program any way you like.

mrweasel 3y ago
So I could compile a program, dynamically link an LGPL library and that's fine, but the moment I statically link the same program I'd be violating the LGPL. I never considered that, don't that make the LGPL a pretty poor license for pretty much anything?
- michaelsbradley 3y ago
  You can link statically, see my reply to parent.
  - phkahler 3y ago
    >> You can link statically, see my reply to parent. You can static link code under the equivalent version of GPL license. The point of the LGPL was to compromise so non-free software could still use free libraries. I was unaware of the static compilation aspect of MPL - that's interesting.
    - deleted 3y ago
      [deleted]
    - michaelsbradley 3y ago
      You can statically link closed/proprietary software with LGPLed code, its just a too common misunderstanding that you can’t do so.
    - dartos 3y ago
      I think the other commenter is wrong. You are restricted from statically linking LGPL code in non free programs unless you follow the restrictions in section 4d of the license
- tom_ 3y ago
  Not necessarily, because it means LGPL libraries are suitable for use with non-free programs. As the library user, this is good, because you potentially get access to free libraries that you'd otherwise be unable to use. (GPL libraries are off limits for non-free programs.) As the library author, this is also good, because your potential user base is widened, but your library can remain free software. (Of course, you could equally spin it that these are bad things - an exercise for the reader.)