Example to minimize redundancy of two libraries. Lua - C library & plain C library?

["Patrick Mc(avery" <patrick@...>]

Hi Everyone

After many long delays I think I am ready to start writing a scientific 
instrument control library. I would like the library to be callable from 
Lua but also just from C without Lua. I am assuming that the best way to 
go about this is to write a plain C core and then a wrapper around it 
with the Lua - C API and then to write another C wrapper around the core 
for a plain C library.

I hope what I have written is clear, if so does this sound logical? is 
there another approach people take to avoid writings two completely 
separate libraries? Are there any examples that might be good to use as 
a design template?

Thanks for reading-Patrick