GPL, yet again. (The kernel is a lot like a shared library)
While I would like to belive that the FSF knew exactly what they were doing,
I am not certain.
It is generally belived that the GPL 'derivative' clauses may actually be
upheld in the case of static libraries. The fact that linking the .o's of
the library directly with your program is equivelent to linking the library
with the object files of your program, seems to verify this.
The question still debated is whether Shared libraries are like this also.
The linux kernel 'copying' file states this:
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
If that statement is true and if it does not qualify as a licence exception,
the following argument would hold:
NOTE! The GPL does *not* cover programs that use shared library
services by normal function calls - this is merely considered normal use
of the shared library, and does *not* fall under the heading of "derived
The thing is that the kernel is indeed much like a library, but not like a
The kernel is a lot like a shared library in that it exists in memory, and
that can be called. It is different mainly in that it stays in memory, and
on some architectures
has special capabilities not available to regular shared libraries.
Note that it is not different by being a critical part of the operating
system, as other libraries,
especially things like the c library, or even the runtime linking library