sysvipc/sys/sem.h

   1 /* Copyright (C) 1995-2019 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 _SYS_SEM_H
  19 #define _SYS_SEM_H      1
  20
  21 #include <features.h>
  22
  23 #define __need_size_t
  24 #include <stddef.h>
  25
  26 /* Get common definition of System V style IPC.  */
  27 #include <sys/ipc.h>
  28
  29 /* Get system dependent definition of `struct semid_ds' and more.  */
  30 #include <bits/sem.h>
  31
  32 #ifdef __USE_GNU
  33 # include <bits/types/struct_timespec.h>
  34 #endif
  35
  36 /* The following System V style IPC functions implement a semaphore
  37    handling.  The definition is found in XPG2.  */
  38
  39 /* Structure used for argument to `semop' to describe operations.  */
  40 struct sembuf
  41 {
  42   unsigned short int sem_num;   /* semaphore number */
  43   short int sem_op;             /* semaphore operation */
  44   short int sem_flg;            /* operation flag */
  45 };
  46
  47
  48 __BEGIN_DECLS
  49
  50 /* Semaphore control operation.  */
  51 extern int semctl (int __semid, int __semnum, int __cmd, ...) __THROW;
  52
  53 /* Get semaphore.  */
  54 extern int semget (key_t __key, int __nsems, int __semflg) __THROW;
  55
  56 /* Operate on semaphore.  */
  57 extern int semop (int __semid, struct sembuf *__sops, size_t __nsops) __THROW;
  58
  59 #ifdef __USE_GNU
  60 /* Operate on semaphore with timeout.  */
  61 extern int semtimedop (int __semid, struct sembuf *__sops, size_t __nsops,
  62                        const struct timespec *__timeout) __THROW;
  63 #endif
  64
  65 __END_DECLS
  66
  67 #endif /* sys/sem.h */