/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */

#ifndef _SEMAPHORE_H
#define _SEMAPHORE_H 1

#include <features.h>
#include <sys/types.h>
#ifdef __USE_XOPEN2K
# define __need_timespec
# include <time.h>
#endif

/* Get the definition for sem_t. */
#include <bits/semaphore.h>


__BEGIN_DECLS

/* Initialize semaphore object SEM to VALUE. If PSHARED then share it
with other processes. */
extern int sem_init (sem_t *__sem, int __pshared, unsigned int __value)
__THROW;
/* Free resources associated with semaphore object SEM. */
extern int sem_destroy (sem_t *__sem) __THROW;

/* Open a named semaphore NAME with open flags OFLAG. */
extern sem_t *sem_open (__const char *__name, int __oflag, ...) __THROW;

/* Close descriptor for named semaphore SEM. */
extern int sem_close (sem_t *__sem) __THROW;

/* Remove named semaphore NAME. */
extern int sem_unlink (__const char *__name) __THROW;

/* Wait for SEM being posted.

This function is a cancellation point and therefore not marked with
__THROW. */
extern int sem_wait (sem_t *__sem);

#ifdef __USE_XOPEN2K
/* Similar to `sem_wait' but wait only until ABSTIME.

This function is a cancellation point and therefore not marked with
__THROW. */
extern int sem_timedwait (sem_t *__restrict __sem,
__const struct timespec *__restrict __abstime);
#endif

/* Test whether SEM is posted. */
extern int sem_trywait (sem_t *__sem) __THROW;

/* Post SEM. */
extern int sem_post (sem_t *__sem) __THROW;

/* Get current value of SEM and store it in *SVAL. */
extern int sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval)
__THROW;


__END_DECLS

#endif /* semaphore.h */