1/* Copyright (C) 2002-2016 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18#ifndef _SEMAPHORE_H
19#define _SEMAPHORE_H 1
20
21#include <features.h>
22#include <sys/types.h>
23#ifdef __USE_XOPEN2K
24# define __need_timespec
25# include <time.h>
26#endif
27
28/* Get the definition for sem_t. */
29#include <bits/semaphore.h>
30
31
32__BEGIN_DECLS
33
34/* Initialize semaphore object SEM to VALUE. If PSHARED then share it
35 with other processes. */
36extern int sem_init (sem_t *__sem, int __pshared, unsigned int __value)
37 __THROW;
38/* Free resources associated with semaphore object SEM. */
39extern int sem_destroy (sem_t *__sem) __THROW;
40
41/* Open a named semaphore NAME with open flags OFLAG. */
42extern sem_t *sem_open (const char *__name, int __oflag, ...) __THROW;
43
44/* Close descriptor for named semaphore SEM. */
45extern int sem_close (sem_t *__sem) __THROW;
46
47/* Remove named semaphore NAME. */
48extern int sem_unlink (const char *__name) __THROW;
49
50/* Wait for SEM being posted.
51
52 This function is a cancellation point and therefore not marked with
53 __THROW. */
54extern int sem_wait (sem_t *__sem);
55
56#ifdef __USE_XOPEN2K
57/* Similar to `sem_wait' but wait only until ABSTIME.
58
59 This function is a cancellation point and therefore not marked with
60 __THROW. */
61extern int sem_timedwait (sem_t *__restrict __sem,
62 const struct timespec *__restrict __abstime);
63#endif
64
65/* Test whether SEM is posted. */
66extern int sem_trywait (sem_t *__sem) __THROWNL;
67
68/* Post SEM. */
69extern int sem_post (sem_t *__sem) __THROWNL;
70
71/* Get current value of SEM and store it in *SVAL. */
72extern int sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval)
73 __THROW;
74
75
76__END_DECLS
77
78#endif /* semaphore.h */
79