Getter & Setter in C - c

Question

i'm facing a problem in C where i'm trying to use some getter and setter to share a variable between multiple source file.
I declare here my variable (ok_button) with a getter and a setter:
variable.c
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <string.h>
#include "../libhd_src/libhd.h"
int ok_button;
void set_ok_button(int value){
ok_button=value;
printf("Setting ok");
}
int get_ok_button(){
return ok_button;
}
Here, when i push a button, it sets the variable to 1. (Can't upload the full code of this source file, but i see in my logs that the function set_ok_button is correctly execuded when i press (i see the printf "Setting OK" everytime i press my button))
button.c
#include "../libhd_src/libhd.h"
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <math.h>
#include <time.h>
void * button_back_center_short(void *arg){
set_ok_button(1);
return 0;
}
And here, i simply check the value of my variable with the getter function.
read.c
#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>
#include <math.h>
#include <time.h>
#include "../../libhd_src/libhd.h"
int main(int argc, char **argv){
while(1){
printf("Value %d", get_ok_button());
usleep(500000);
}
}
The problem is that the value shown in read.c is always "0" even when i press my button and set the value to 1...
Does someone understand what's wrong ? Feel free to tell me if you see a better solution to do that :)

Answer 1

I think your problem may be that you have multiple set_ok_button and get_ok_button functions in different files. Make sure you only have them defined in one file, and in a header add 2 lines declaring (but not defining) the functions:
void set_ok_button(int value);
int get_ok_button();