/* Copyright (C) 1995-2018 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, see

   <http://www.gnu.org/licenses/>.  */

#ifndef _SYS_SEM_H

# error "Never include <bits/sem.h> directly; use <sys/sem.h> instead."

#endif

#include <sys/types.h>

/* Flags for `semop'.  */

#define SEM_UNDO	0x1000		/* undo the operation on exit */

/* Commands for `semctl'.  */

#define GETPID		11		/* get sempid */

#define GETVAL		12		/* get semval */

#define GETALL		13		/* get all semval's */

#define GETNCNT		14		/* get semncnt */

#define GETZCNT		15		/* get semzcnt */

#define SETVAL		16		/* set semval */

#define SETALL		17		/* set all semval's */

/* Data structure describing a set of semaphores.  */

struct semid_ds

{

  struct ipc_perm sem_perm;		/* operation permission struct */

  __time_t sem_otime;			/* last semop() time */

  __time_t sem_ctime;			/* last time changed by semctl() */

  unsigned short int sem_nsems;		/* number of semaphores in set */

};

/* The user should define a union like the following to use it for arguments

   for `semctl'.

   union semun

   {

     int val;				<= value for SETVAL

     struct semid_ds *buf;		<= buffer for IPC_STAT & IPC_SET

     unsigned short int *array;		<= array for GETALL & SETALL

     struct seminfo *__buf;		<= buffer for IPC_INFO

   };

   Previous versions of this file used to define this union but this is

   incorrect.  One can test the macro _SEM_SEMUN_UNDEFINED to see whether

   one must define the union or not.  */

#define _SEM_SEMUN_UNDEFINED	1