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/* Copyright (C) 1995-2013 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 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/>. */
#include <errno.h>
#include <sys/shm.h>
#include <ipc_priv.h>
#include <sysdep.h>
#include <unistd.h>
#include <sys/syscall.h>
/* Attach the shared memory segment associated with SHMID to the data
segment of the calling process. SHMADDR and SHMFLG determine how
and where the segment is attached. */
void *
shmat (shmid, shmaddr, shmflg)
int shmid;
const void *shmaddr;
int shmflg;
{
INTERNAL_SYSCALL_DECL(err);
unsigned long resultvar;
void *__unbounded raddr;
#if __BOUNDED_POINTERS__
size_t length = ~0;
struct shmid_ds shmds;
/* It's unfortunate that we need to make another system call to get
the shared memory segment length... */
if (shmctl (shmid, IPC_STAT, &shmds) == 0)
length = shmds.shm_segsz;
#endif
resultvar = INTERNAL_SYSCALL (ipc, err, 5, IPCOP_shmat,
shmid, shmflg,
(long int) __ptrvalue (&raddr),
__ptrvalue ((void *) shmaddr));
if (INTERNAL_SYSCALL_ERROR_P (resultvar, err))
{
__set_errno (INTERNAL_SYSCALL_ERRNO (resultvar, err));
return (void *) -1l;
}
return raddr;
}
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