[SOLVED] Getters and setters in pure C?

Getters and setters in pure C?

Can I use getters and setters in pure C instead of using extern variables?

Solution

First of all, don't listen to anyone saying "there is no object-orientation in language x" because they have truly not understood that OO is a program design method, completely apart from language syntax.

Some languages have elegant ways to implement OO, some have not. Yet it is possible to write an object-oriented program in any language, for example in C. Similarly, your program will not automagically get a proper OO design just because you wrote it in Java, or because you used certain language keywords.

The way you implement private encapsulation in C is a bit more crude than in languages with OO support, but it does like this:

// module.h

void set_x (int n);
int get_x (void);

// module.c

static int x; // private variable

void set_x (int n)
{
  x = n;
}

int get_x (void)
{
  return x;
}

// main.c

#include "module.h"

int main (void)
{
  set_x(5);
  printf("%d", get_x());
}

Can call it "class" or "ADT" or "code module" as you prefer.

This is how every reasonable C program out there is written. And has been written for the past 30-40 years or so, as long as program design has existed. If you say there are no setters/getters in a C program, then that is because you have no experience of using C.

EDIT: For completeness, the thread-safe, multi-instance version of the above is also possible using "opaque type", see How to do private encapsulation in C?