Thread: Visibility

I'm wondering how visibility is granted to one file while being restricted in another.

Say I have a function 'void second_hello()' which is defined in the second.c file and I want that to be available in the first.c file but not in the main.c file.. Basically I want to call a function in first.c which calls the function in second.c because I want the function in second.c hidden from main.c. Hope that makes sense.

Here's what I tried.

second.h

Code:

#ifndef SECOND__HH
#define SECOND__HH

void second_hello();

#endif

second.c

Code:

#include <stdio.h>
#include "second.h"

void second_hello() {//this should only be available in first.c
  fputs("Hello world from the second!\n", stdout);
}

first.h

Code:

#ifndef FIRST__HH
#define FIRST__HH

void first_hello();

#endif

first.c

Code:

#include "first.h"
#include "second.h"

void first_hello() {
  second_hello();
}

main.c

Code:

#include <stdio.h>
#include "first.h"

int main(int argc, char ** argv) {
  first_hello();//which calls second_hello()
  return 0;
}

Is the above code a proper way to restrict visibility of 'void second_hello()'?