Differences from GPL to LGPL

[Peter Roozemaal]

Ian Stirling wrote:
> Peter Roozemaal wrote:
>> Javier Palacios wrote:
>>
>>> That is basically static vs. dynamic linking. Most of the references
>>> I've found state that linking with GPL libraries means derivative work
>>> and the source must be GPL.
>>>
>>> And my view is that it only happens if the linking is static. If dynamic
>>> linking is done, no GPL covered binaries must be released to user,
>>> and, at least theoretically, the released binaries should be able to use
>>> dinamically any library with the same API.
>>>
>>> That has been my view for a long time, but a recent discussion within
>>> my current company (desperately searching for LGPL code) showed
>>> me that it was not a shared opinion.
>>
>> While your analysis is correct for your binary, your customer, the end
>> user, would need a copy of the binaries of the shared library. If you
>> supply that copy, you implicitly accept the GPL by distributing a copy
>> of that shared library. And via your (incidental) distribution of the
>> shared library the conditions of the GPL extend to your code.
> 
> Doesn't the distribution of binaries of a LGPL binary simply mean that
> you need to offer source for that LGPL binary?
> Not anything that may be linked by it?
> 
We were discussing issues of dynamically linking with a GPL library; the
obligations after linking with a LGPL library are spelled out in section
6 of the LGPLv2.1:
 - make source code for the library available
 - offer source or linkable object code (a dynamically linked
   executable) for the rest of the application

Off course the discussion about the limits of copyrights that Javier
brought up applies to LGPL code too. However there is less reason to
play his game with LGPL code.

Peter.