1/* Copyright (C) 2002-2025 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   <https://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# include <bits/types/struct_timespec.h>
 25#endif
 26
 27/* Get the definition for sem_t.  */
 28#include <bits/semaphore.h>
 29
 30
 31__BEGIN_DECLS
 32
 33/* Initialize semaphore object SEM to VALUE.  If PSHARED then share it
 34   with other processes.  */
 35extern int sem_init (sem_t *__sem, int __pshared, unsigned int __value)
 36  __THROW __nonnull ((1));
 37
 38/* Free resources associated with semaphore object SEM.  */
 39extern int sem_destroy (sem_t *__sem) __THROW __nonnull ((1));
 40
 41/* Open a named semaphore NAME with open flags OFLAG.  */
 42extern sem_t *sem_open (const char *__name, int __oflag, ...)
 43  __THROW __nonnull ((1));
 44
 45/* Close descriptor for named semaphore SEM.  */
 46extern int sem_close (sem_t *__sem) __THROW __nonnull ((1));
 47
 48/* Remove named semaphore NAME.  */
 49extern int sem_unlink (const char *__name) __THROW __nonnull ((1));
 50
 51/* Wait for SEM being posted.
 52
 53   This function is a cancellation point and therefore not marked with
 54   __THROW.  */
 55extern int sem_wait (sem_t *__sem) __nonnull ((1));
 56
 57#ifdef __USE_XOPEN2K
 58/* Similar to `sem_wait' but wait only until ABSTIME.
 59
 60   This function is a cancellation point and therefore not marked with
 61   __THROW.  */
 62# ifndef __USE_TIME64_REDIRECTS
 63extern int sem_timedwait (sem_t *__restrict __sem,
 64			  const struct timespec *__restrict __abstime)
 65  __nonnull ((1, 2));
 66# else
 67#  ifdef __REDIRECT
 68extern int __REDIRECT (sem_timedwait,
 69                       (sem_t *__restrict __sem,
 70                        const struct timespec *__restrict __abstime),
 71                        __sem_timedwait64)
 72  __nonnull ((1, 2));
 73#  else
 74#   define sem_timedwait __sem_timedwait64
 75#  endif
 76# endif
 77#endif
 78
 79#ifdef __USE_GNU
 80# ifndef __USE_TIME64_REDIRECTS
 81extern int sem_clockwait (sem_t *__restrict __sem,
 82			  clockid_t clock,
 83			  const struct timespec *__restrict __abstime)
 84  __nonnull ((1, 3));
 85# else
 86#  ifdef __REDIRECT
 87extern int __REDIRECT (sem_clockwait,
 88                       (sem_t *__restrict __sem,
 89                        clockid_t clock,
 90                        const struct timespec *__restrict __abstime),
 91                        __sem_clockwait64)
 92  __nonnull ((1, 3));
 93#  else
 94#   define sem_clockwait __sem_clockwait64
 95#  endif
 96# endif
 97#endif
 98
 99/* Test whether SEM is posted.  */
100extern int sem_trywait (sem_t *__sem) __THROWNL __nonnull ((1));
101
102/* Post SEM.  */
103extern int sem_post (sem_t *__sem) __THROWNL __nonnull ((1));
104
105/* Get current value of SEM and store it in *SVAL.  */
106extern int sem_getvalue (sem_t *__restrict __sem, int *__restrict __sval)
107  __THROW __nonnull ((1, 2));
108
109
110__END_DECLS
111
112#endif	/* semaphore.h */