C library naming conventions

Question

Introduction

Hello folks, I recently learned to program in C! (This was a huge step for me, since C++ was the first language, I had contact with and scared me off for

Answer 1

The struct way that Ken mentions would look something like this:

struct MyCoolApi
{
  int (*add)(int x, int y);
};

MyCoolApi * my_cool_api_initialize(void);

Then clients would do:

#include 
#include 

#include "mycoolapi.h"

int main(void)
{
  struct MyCoolApi *api;

  if((api = my_cool_api_initialize()) != NULL)
  {
    int sum = api->add(3, 39);

    printf("The cool API considers 3 + 39 to be %d\n", sum);
  }
  return EXIT_SUCCESS;
}

This still has "namespace-issues"; the struct name (called the "struct tag") needs to be unique, and you can't declare nested structs that are useful by themselves. It works well for collecting functions though, and is a technique you see quite often in C.

UPDATE: Here's how the implementation side could look, this was requested in a comment:

#include "mycoolapi.h"

/* Note: This does **not** pollute the global namespace,
 * since the function is static.
*/
static int add(int x, int y)
{
  return x + y;
}

struct MyCoolApi * my_cool_api_initialize(void)
{
  /* Since we don't need to do anything at initialize,
   * just keep a const struct ready and return it.
  */
  static const struct MyCoolApi the_api = {
    add
  };

  return &the_api;
}