Hi,
> 	I need to release a firmware to a customer, and he must be allowed
> to modify one of the source files (writen in C).
> 	I don't want to give him the whole code, but I would like to give
> him a (unknown format) file + the user modificable routine.
> 	Anyone can give me a pointer on how to accomplish this?
you could give them the object files the compiler generates and the linker uses. This will obscure things somewhat but there will still be lots of information like procedure names and global variable names in there as theese are needed for linking. 

I don't see how you are going to get much better than that, you could pre-obscure theese things out of the code to some extent but whatever you do you will leave some clues.



-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist