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#include <stdio.h>
#include <sys/types.h>
#include <sys/sem.h>
#include <errno.h>
#define MAX_SEMAPHORES  5
int main(int argc,char *argv[])
{
   int i, ret, semid;
   unsigned short sem_array[MAX_SEMAPHORES];
   unsigned short sem_read_array[MAX_SEMAPHORES];

   union semun
{
     int val;
     struct semid_ds *buf;
     unsigned short *array;
   } arg;

   semid = semget( IPC_PRIVATE, MAX_SEMAPHORES,IPC_CREAT | 0666 );

   if (semid != -1)
{
     /* Initialize the sem_array */
     for ( i = 0 ; i < MAX_SEMAPHORES ; i++ )
  {
       sem_array[i] = (unsigned short)(i+1);
     }
     /* Update the arg union with the sem_array address */
     arg.array = sem_array;
     /* Set the values of the semaphore-array */
     ret = semctl( semid, 0, SETALL, arg);
     if (ret == -1) printf("SETALL failed (%d)\n", errno);
        /* Update the arg union with another array for read */
        arg.array = sem_read_array;
        /* Read the values of the semaphore array */
ret = semctl( semid, 0, GETALL, arg );
if (ret == -1) printf("GETALL failed (%d)\n", errno);
  /* print the sem_read_array */
  for ( i = 0 ; i < MAX_SEMAPHORES ; i++ )
  {
    printf("Semaphore %d, value %d\n", i, sem_read_array[i] );

  }
  /* Use GETVAL in a similar manner */
  for ( i = 0 ; i < MAX_SEMAPHORES ; i++ )
  {
    ret = semctl( semid, i, GETVAL );
    printf("Semaphore %d, value %d\n", i, ret );
  }
  /* Delete the semaphore */
  ret = semctl( semid, 0, IPC_RMID );
}
else
      printf("Could not allocate semaphore (%d)\n", errno);
return 0;