Including a header file from another directory

Question

I have a main directory A with two sub directories B and C.

Directory B contains a header file structures.c

Answer 1

If you work on a Makefile project or simply run your code from command line, use

gcc -IC main.c

where -I option adds your C directory to the list of directories to be searched for header files, so you'll be able to use #include "structures.h"anywhere in your project.