MIT-Curricular/OS/C/theory/sync/semaextraposts.c

#include <stdio.h>
#include <pthread.h>
#include <semaphore.h>
#include <fcntl.h>
#include <stdatomic.h>

atomic_int semaphore_value = 5;
sem_t *my_semaphore;

int main(){
    my_semaphore = sem_open("/my_sem", O_CREAT, 0644, atomic_load(&semaphore_value));
    int sem_val = atomic_load(&semaphore_value);
    printf("Initial semaphore value: %d\n", sem_val);

    sem_post(my_semaphore);
    atomic_fetch_add(&semaphore_value, 1);
    sem_post(my_semaphore);
    atomic_fetch_add(&semaphore_value, 1);
    sem_post(my_semaphore);
    atomic_fetch_add(&semaphore_value, 1);

    sem_val = atomic_load(&semaphore_value);
    printf("Semaphore value after extra posts: %d\n", sem_val);

    sem_close(my_semaphore);
    sem_unlink("/my_sem");
    return 0;
}