#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/msg.h>
#include <sys/sem.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <semaphore.h>

#define CLE_UNIQUE 1234
#define NUM_SEMAPHORE 0

/*struct sembuf
{
  unsigned short sem_num;
  short sem_op;
  short sem_flag;
};*/

union semun
{
    int val;
    struct semid_ds * buf;
    ushort * array;
};



int main(int argc, char* argv[])
{
    int f = 0;

    union semun init_jeton, tester_jeton;
    init_jeton.val = 1;
    tester_jeton.val = 0;
    struct sembuf prendre_jeton = { NUM_SEMAPHORE, -1, IPC_NOWAIT};
    struct sembuf poser_jeton = { NUM_SEMAPHORE, 1, IPC_NOWAIT};
    int id_semaphore = semget(CLE_UNIQUE, 1, IPC_CREAT | 0666);
    f = fork();

    for(int i = 0; i<5 ; i++)
    {
      while(semctl(id_semaphore, 0 , GETVAL, tester_jeton) < 1)
      {
        printf("id : %d", f);
      }
      semop(id_semaphore, &prendre_jeton, 1);
      printf("id : %d", f);
      semop(id_semaphore, &poser_jeton, 1);
    }
  return 0;
}