I have a C binary file(.so as extension) which is delivered by a product.
How do i use this functionalities of this .so file in my C program?
How can in link the .so to my C program?
put the file in a publicly accessible directory (usually the directory tree associated with the product install), unless you are the only one running the code. Let's call it mylib.so and assume you put it in $HOME.
cc myprog.c -L $HOME -o myprog
This is probably oversimplified a little but you can see just what you need.