Advanced Programming in the UNIX® Environment

ptg10805159

880 Function Prototypes Appendix A

int semget(key_tkey,intnsems,intflag);

<sys/sem.h> p. 567

flag:IPC_CREAT, IPC_EXCL

Returns: semaphore ID if OK,−1 on error

int sem_getvalue(sem_t *restrictsem,int *restrictvalp);

<semaphore.h> p. 582

Returns: 0 if OK,−1 on error

int sem_init(sem_t *sem,intpshared,unsigned intvalue);

<semaphore.h> p. 582

Returns: 0 if OK,−1 on error

int semop(intsemid,struct sembufsemoparray[], size_tnops);

<sys/sem.h> p. 568

Returns: 0 if OK,−1 on error

sem_t *sem_open(const char *name,intoflag,... /* mode_tmode,

unsigned intvalue*/ );

<semaphore.h> p. 579

flag:IPC_CREAT, IPC_EXCL

Returns: pointer to semaphore if OK,SEM_FAILEDon error

int sem_post(sem_t *sem);

<semaphore.h> p. 582

Returns: 0 if OK,−1 on error

int sem_timedwait(sem_t *restrictsem,

const struct timespec *restricttsptr);

<semaphore.h> p. 581

<time.h>

Returns: 0 if OK,−1 on error

int sem_trywait(sem_t *sem);

<semaphore.h>

Returns: 0 if OK,−1 on error

int sem_unlink(const char *name);

<semaphore.h> p. 580

Returns: 0 if OK,−1 on error

int sem_wait(sem_t *sem);

<semaphore.h> p. 581

Returns: 0 if OK,−1 on error