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#ifndef SEMAPHORE_H
#define SEMAPHORE_H
#include <sys/ipc.h>
#include <sys/sem.h>
#ifndef SEMUN_IN_SEM_H
union semun
{
int val; /* value for SETVAL */
struct semid_ds *buf; /* buffer for IPC_STAT, IPC_SET */
unsigned short int *array; /* array for GETALL, SETALL */
struct seminfo *__buf; /* buffer for IPC_INFO */
};
#endif
class Semaphore
{
public:
// numSems is the number of semaphores to be in the set
// semKey is the ID number for the semaphore set
// val is the initial value for the semaphores, no values will be assigned
// if the default (0) is specified.
Semaphore(int semKey, int numSems = 1, int val = 0);
// clear the semaphores and return an error code.
int clear_sem();
// create the semaphores
// count is the initial value assigned to each semaphore
int create(int count);
// get the handle to a semaphore set previously created
int get_semid();
int decrement_and_wait(int nr_sem);
int get_mutex();
int put_mutex();
private:
union semun m_arg;
int m_semid;
int m_semflg;
bool m_semopen;
int m_semKey;
int m_numSems;
};
#endif
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