1/*
2 * pthread_mutexattr_getpshared.c
3 *
4 * Description:
5 * This translation unit implements mutual exclusion (mutex) primitives.
6 *
7 * --------------------------------------------------------------------------
8 *
9 *      Pthreads-win32 - POSIX Threads Library for Win32
10 *      Copyright(C) 1998 John E. Bossom
11 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
12 *
13 *      Contact Email: rpj@callisto.canberra.edu.au
14 *
15 *      The current list of contributors is contained
16 *      in the file CONTRIBUTORS included with the source
17 *      code distribution. The list can also be seen at the
18 *      following World Wide Web location:
19 *      http://sources.redhat.com/pthreads-win32/contributors.html
20 *
21 *      This library is free software; you can redistribute it and/or
22 *      modify it under the terms of the GNU Lesser General Public
23 *      License as published by the Free Software Foundation; either
24 *      version 2 of the License, or (at your option) any later version.
25 *
26 *      This library is distributed in the hope that it will be useful,
27 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
28 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
29 *      Lesser General Public License for more details.
30 *
31 *      You should have received a copy of the GNU Lesser General Public
32 *      License along with this library in the file COPYING.LIB;
33 *      if not, write to the Free Software Foundation, Inc.,
34 *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
35 */
36
37#include "pthread.h"
38#include "implement.h"
39
40
41int
42pthread_mutexattr_getpshared (const pthread_mutexattr_t * attr, int *pshared)
43     /*
44      * ------------------------------------------------------
45      * DOCPUBLIC
46      *      Determine whether mutexes created with 'attr' can be
47      *      shared between processes.
48      *
49      * PARAMETERS
50      *      attr
51      *              pointer to an instance of pthread_mutexattr_t
52      *
53      *      pshared
54      *              will be set to one of:
55      *
56      *                      PTHREAD_PROCESS_SHARED
57      *                              May be shared if in shared memory
58      *
59      *                      PTHREAD_PROCESS_PRIVATE
60      *                              Cannot be shared.
61      *
62      *
63      * DESCRIPTION
64      *      Mutexes creatd with 'attr' can be shared between
65      *      processes if pthread_mutex_t variable is allocated
66      *      in memory shared by these processes.
67      *      NOTES:
68      *              1)      pshared mutexes MUST be allocated in shared
69      *                      memory.
70      *              2)      The following macro is defined if shared mutexes
71      *                      are supported:
72      *                              _POSIX_THREAD_PROCESS_SHARED
73      *
74      * RESULTS
75      *              0               successfully retrieved attribute,
76      *              EINVAL          'attr' is invalid,
77      *
78      * ------------------------------------------------------
79      */
80{
81  int result;
82
83  if ((attr != NULL && *attr != NULL) && (pshared != NULL))
84    {
85      *pshared = (*attr)->pshared;
86      result = 0;
87    }
88  else
89    {
90      result = EINVAL;
91    }
92
93  return (result);
94
95}				/* pthread_mutexattr_getpshared */
96