LGPL and DLLs
kelly at acoin.com
Sun Feb 13 13:19:12 UTC 2005
The LGPL says that you can use an LGPLed library in a commercial setting.
However, they also make this requirement that you have to be able to
re-link the LGPL program into the proprietary program. My [IANAL]
understanding of the LGPL's intent in the re-linking language is so that
you can replace the part of a program that is under LGPL with a newer
version, or your own version, without the proprietary company's permission.
I kind of get what they are doing, trying to make the program semi-open, so
that you can still change things that are part of the library.
If you put the LGPL library code into a DLL, and give instructions on how
to construct that DLL (or the project already comes in DLL form in the
first place) then is this generally understood to fulfill the re-linking
requirements of the LGPL?
Assuming that the DLL is a solution to the re-linking issue, is the
proprietary company then within it's rights to say, "If, however, you do
replace this DLL with another version, you've gone off the reservation, and
we can't provide technical support for you until you put a 'blessed'
version of the DLL back into your installation."
It seems unfair to expect a closed source company to provide support for a
DLL that has been changed by the end user under an open source license. The
re-linking clause makes closed source shops nervous about using code
licensed under the LGPL. (At least that's my personal experience.)
At the same time, it seems unwise for the open source community to refuse
the help they could get from commercial "moles" who are willing to work on
their software under the context of the LGPL, if they could use it for
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