Non-GPL C (or R) inside of a package

[...]

My case is a bit more subtle, as the code that I am writing makes no
use of any GPL code, aside from the compilation and linking to allow
GPL "R" code to access it.

[...]

Just ask people from the FSF, if your issue is complicated.

Or ask the owner of the nmon-GPLed code, if it is possible
to make it open for your project.

That does not necessarily mean that the same code in olther
products of the company also needs to become open.

It's possible to make a "fork".

You just can't make GPLed code again closed.


Ciao,
   Oliver