glibc/sysdeps/unix/sysv/linux/sys/shm_buf.h

/* Copyright (C) 1995 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, August 1995.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

#ifndef _SYS_SHM_BUF_H
#define _SYS_SHM_BUF_H

#include <features.h>
#include <sys/types.h>

/* Flags for `shmat'.  */
#define SHM_RDONLY	010000		/* attach read-only else read-write */
#define SHM_RND		020000		/* round attach address to SHMLBA */
#define SHM_REMAP	040000		/* take-over region on attach */

/* Commands for `shmctl'.  */
#define SHM_LOCK	11		/* lock segment (root only) */
#define SHM_UNLOCK	12		/* unlock segment (root only) */


__BEGIN_DECLS

/* Data structure describing a set of semaphores.  */
struct shmid_ds
{
  struct ipc_perm sem_perm;		/* operation permisson struct */
  int shm_segsz;			/* size of segment in bytes */
  __time_t sem_atime;			/* time of last shmat() */
  __time_t sem_dtime;			/* time of last shmdt() */
  __time_t sem_ctime;			/* time of last change by shmctl() */
  __pid_t shm_cpid;			/* pid of creator */
  __pid_t shm_lpid;			/* pid of last shmop */
  unsigned short int shm_nattch;	/* number of current attaches */
  unsigned short int __shm_npages;	/* size of segment (pages) */
  unsigned long int *__shm_pages;	/* array of ptrs to frames -> SHMMAX */
  struct vm_area_struct *__attaches;	/* descriptors for attaches */
};

__END_DECLS

#endif /* sys/shm_buf.h */