Question

I have these two files, functions.c and constants.h.

functions.c has this line:

#include "constants.h"

However, when I try to compile functions.c, functions.c functions can’t find these constants from constants.c. These are const type constants. I know it’s a very noobish problem, but I don’t know the solution.

EDIT:
Files content (some of them):

functions.c:

#include <string.h>
#include "Directivas.h"
...
int hayDirectivaInclude(char* buffer) {
    if (strncmp(include, buffer, longInclude) == 0)
        return 1;
    else
        return 0;
}

constants.h:

const char include[10] = { '#', 'i', 'n', 'c', 'l', 'u', 'd', 'e', ' ', 0 };
const int longInclude = 9;

Answer 1

Your constants.h must contain extern references to the constants.

For example, suppose you had: const char* COOL_STRING = "Erandros is cool." in constants.c. In order for functions.c to know about this string, you must inform it of its existence by writing extern char* COOL_STRING; somewhere, such as in constants.h