Question regarding a LGPL program and closed-source plugin
On debian-chinese list someone has expressed an intension to package a
Chinese input server SCIM and its plugins for Debian. The input server
program SCIM is released under LGPL. However the server alone doesn't do
anything interesting. The real input methods are developed as plugins for
the server. Upon running the chosen plugin(s) will be loaded into the
server's space through dlopen. Then the server will get pointers of
functions from the plugin and call them as certain events occur. In a
nutshell it's very similar to how xmms and its plugins work. One of the
plugins, arguably the only one that most people will be interested, is
binary only. So we have been discussing whether we can legally distribute
this binary only plugin. If it was GPL, we know that a binary only plugin
is not allowed. But will LGPL make a difference? so my questions are:
1. Could the plugin be considered as a "work that uses the Library"
according to section 5 of LGPL, thus its distribution is outside of the
scope of LGPL? The thing confused me is that the server program is
not a typical library and the plugin is not a typical program that "is
designed to work with the Library by being compiled or linked with it".
2. The plugin uses some data structures and macros from many header files
from the server program. As such, does the generated object code (the so
file in this case) have to be considered a "derivative work of the
Library", thus subject to LGPL license?
3. Is it needed, for binary only plugin to be legal, to single out the
plugin APIs and put them under a different license?
Thank you in advance
PS: Please CC me when you reply since I'm not on this list. Thank you.