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/****************************************************************************
* mm/shm/shmget.c
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/shm.h>
#include <sys/ipc.h>
#include <errno.h>
#ifdef CONFIG_MM_SHM
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: shmget
*
* Description:
* The shmget() function will return the shared memory identifier
* associated with key.
*
* A shared memory identifier, associated data structure, and shared
* memory segment of at least size bytes is created for key if one of the
* following is true:
*
* - The argument key is equal to IPC_PRIVATE.
* - The argument key does not already have a shared memory identifier
* associated with it and (shmflg & IPC_CREAT) is non-zero.
*
* Upon creation, the data structure associated with the new shared memory
* identifier will be initialized as follows:
*
* - The values of shm_perm.cuid, shm_perm.uid, shm_perm.cgid, and
* shm_perm.gid are set equal to the effective user ID and effective
* group ID, respectively, of the calling process.
* - The low-order nine bits of shm_perm.mode are set equal to the low-
* order nine bits of shmflg.
* - The value of shm_segsz is set equal to the value of size.
* - The values of shm_lpid, shm_nattch, shm_atime, and shm_dtime are
* set equal to 0.
* - The value of shm_ctime is set equal to the current time.
*
* When the shared memory segment is created, it will be initialized with
* all zero values.
*
* Input Parameters:
* key - The key that is used to access the unique shared memory
* identifier.
* size - The shared memory region that is created will be at least
* this size in bytes.
* shmflgs - See IPC_* definitions in sys/ipc.h. Only the values
* IPC_PRIVATE or IPC_CREAT are supported.
*
* Returned Value:
* Upon successful completion, shmget() will return a non-negative
* integer, namely a shared memory identifier; otherwise, it will return
* -1 and set errno to indicate the error.
*
* - EACCES
* A shared memory identifier exists for key but operation permission
* as specified by the low-order nine bits of shmflg would not be
* granted.
* - EEXIST
* A shared memory identifier exists for the argument key but
* (shmflg & IPC_CREAT) && (shmflg & IPC_EXCL) are non-zero.
* - EINVAL
* A shared memory segment is to be created and the value of size is
* less than the system-imposed minimum or greater than the system-
* imposed maximum.
* - EINVAL
* No shared memory segment is to be created and a shared memory
* segment exists for key but the size of the segment associated with
* it is less than size and size is not 0.
* - ENOENT
* A shared memory identifier does not exist for the argument key and
* (shmflg & IPC_CREAT) is 0.
* - ENOMEM
* A shared memory identifier and associated shared memory segment
* will be created, but the amount of available physical memory is
* not sufficient to fill the request.
* - ENOSPC
* A shared memory identifier is to be created, but the system-imposed
* limit on the maximum number of allowed shared memory identifiers
* system-wide would be exceeded.
*
****************************************************************************/
int shmget(key_t key, size_t size, int shmflg)
{
#warning Not implemented
set_errno(ENOSYS);
return ERROR;
}
#endif /* CONFIG_MM_SHM */
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