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Edit File: sem.h

/* Copyright (C) 1995-2021 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
   <https://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>
#include <bits/timesize.h>
#include <bits/types/struct_semid_ds.h>
#include <bits/types/struct_semid64_ds.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 */

/* 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

#ifdef __USE_MISC

/* ipcs ctl cmds */
# define SEM_STAT 18
# define SEM_INFO 19
# define SEM_STAT_ANY 20

struct  seminfo
{
  int semmap;
  int semmni;
  int semmns;
  int semmnu;
  int semmsl;
  int semopm;
  int semume;
  int semusz;
  int semvmx;
  int semaem;
};

#endif /* __USE_MISC */