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glibc  2.9
msync.c
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00001 /* msync -- Synchronize mapped memory to external storage.  Mach version.
00002    Copyright (C) 2002, 2005 Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004 
00005    The GNU C Library is free software; you can redistribute it and/or
00006    modify it under the terms of the GNU Lesser General Public
00007    License as published by the Free Software Foundation; either
00008    version 2.1 of the License, or (at your option) any later version.
00009 
00010    The GNU C Library is distributed in the hope that it will be useful,
00011    but WITHOUT ANY WARRANTY; without even the implied warranty of
00012    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00013    Lesser General Public License for more details.
00014 
00015    You should have received a copy of the GNU Lesser General Public
00016    License along with the GNU C Library; if not, write to the Free
00017    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00018    02111-1307 USA.  */
00019 
00020 #include <sys/types.h>
00021 #include <sys/mman.h>
00022 #include <errno.h>
00023 #include <mach.h>
00024 
00025 /* Some Mach variants have vm_msync and some don't.  Those that have it
00026    define the VM_SYNC_* bits when we include <mach/mach_types.h>.  */
00027 
00028 #ifndef VM_SYNC_SYNCHRONOUS
00029 # include <misc/msync.c>
00030 #else
00031 
00032 /* Synchronize the region starting at ADDR and extending LEN bytes with the
00033    file it maps.  Filesystem operations on a file being mapped are
00034    unpredictable before this is done.  */
00035 
00036 int
00037 msync (__ptr_t addr, size_t len, int flags)
00038 {
00039   vm_sync_t sync_flags = 0;
00040   kern_return_t err;
00041 
00042   if (flags & MS_SYNC)
00043     sync_flags |= VM_SYNC_SYNCHRONOUS;
00044   if (flags & MS_ASYNC)
00045     sync_flags |= VM_SYNC_ASYNCHRONOUS;
00046   if (flags & MS_INVALIDATE)
00047     sync_flags |= VM_SYNC_INVALIDATE;
00048 
00049   if (err = __vm_msync (__mach_task_self (),
00050                      (vm_address_t) addr, (vm_size_t) len, sync_flags))
00051     {
00052       errno = err;
00053       return -1;
00054     }
00055   return 0;
00056 }
00057 #endif