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/****************************************************************************
* include/sys/shm.h
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_SYS_SHM_H
#define __INCLUDE_SYS_SHM_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <time.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Definitions required by POSIX */
#define SHM_RDONLY 0x01 /* Attach read-only (else read-write) */
#define SHM_RND 0x02 /* Round attach address to SHMLBA */
/* Segment low boundary address multiple */
#ifdef CONFIG_SHM_SHMLBA
# define SHMLBA CONFIG_SHM_SHMLBA
#else
# define SHMLBA 0x0
#endif
/****************************************************************************
* Public Type Definitions
****************************************************************************/
/* Unsigned integer used for the number of current attaches that must be
* able to store values at least as large as a type unsigned short.
*/
typedef unsigned short shmatt_t;
struct shmid_ds
{
struct ipc_perm shm_perm; /* Operation permission structure */
size_t shm_segsz; /* Size of segment in bytes */
pid_t shm_lpid; /* Process ID of last shared memory operation */
pid_t shm_cpid; /* Process ID of creator */
shmatt_t shm_nattch; /* Number of current attaches */
time_t shm_atime; /* Time of last shmat() */
time_t shm_dtime; /* Time of last shmdt() */
time_t shm_ctime; /* Time of last change by shmctl() */
};
/****************************************************************************
* Public Data
****************************************************************************/
#undef EXTERN
#if defined(__cplusplus)
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
FAR void *shmat(int shmid, FAR const void *shmaddr, int shmflg);
int shmctl(int shmid, int cmd, FAR struct shmid_ds *buf);
int shmdt(FAR const void *shmaddr);
int shmget(key_t key, size_t size, int shmflg);
#undef EXTERN
#if defined(__cplusplus)
}
#endif
#endif /* __INCLUDE_SYS_SHM_H */
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