sysvipc/sys/sem.h

   1 /* Copyright (C) 1995 Free Software Foundation, Inc.
   2 This file is part of the GNU C Library.
   3 Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.
   4
   5 The GNU C Library is free software; you can redistribute it and/or
   6 modify it under the terms of the GNU Library General Public License as
   7 published by the Free Software Foundation; either version 2 of the
   8 License, or (at your option) any later version.
   9
  10 The GNU C Library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 Library General Public License for more details.
  14
  15 You should have received a copy of the GNU Library General Public
  16 License along with the GNU C Library; see the file COPYING.LIB.  If
  17 not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18 Boston, MA 02111-1307, USA.  */
  19
  20 #ifndef _SYS_SEM_H
  21 #define _SYS_SEM_H
  22
  23 #include <features.h>
  24 #include <sys/types.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 <sys/sem_buf.h>
  31
  32 __BEGIN_DECLS
  33
  34 /* The following System V style IPC functions implement a semaphore
  35    handling.  The definition is found in XPG2.  */
  36
  37 /* Structure used for argument to `semop' to describe operations.  */
  38 struct sembuf
  39 {
  40   short int sem_num;            /* semaphore number */
  41   short int sem_op;             /* semaphore operation */
  42   short int sem_flg;            /* operation flag */
  43 };
  44
  45
  46 /* Semaphore control operation.  */
  47 extern int semctl __P ((int __semid, int __semnum, int __cmd,
  48                         union semun __arg));
  49
  50 /* Get semaphore.  */
  51 extern int semget __P ((key_t __key, int __nsems, int __semflg));
  52
  53 /* Operate on semaphore.  */
  54 extern int semop __P ((int __semid, struct sembuf *__sops,
  55                        unsigned int __nsops));
  56
  57 __END_DECLS
  58
  59 #endif /* sys/sem.h */