1 /*
2 * pthread_mutexattr_getpshared.c
3 *
4 * Description:
5 * This translation unit implements mutual exclusion (mutex) primitives.
6 *
7 * --------------------------------------------------------------------------
8 *
9 * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
10 * Copyright(C) 2008 Jason Schmidlapp
11 *
12 * Contact Email: jschmidlapp@users.sourceforge.net
13 *
14 *
15 * Based upon Pthreads-win32 - POSIX Threads Library for Win32
16 * Copyright(C) 1998 John E. Bossom
17 * Copyright(C) 1999,2005 Pthreads-win32 contributors
18 *
19 * Contact Email: rpj@callisto.canberra.edu.au
20 *
21 * The original list of contributors to the Pthreads-win32 project
22 * is contained in the file CONTRIBUTORS.ptw32 included with the
23 * source code distribution. The list can also be seen at the
24 * following World Wide Web location:
25 * http://sources.redhat.com/pthreads-win32/contributors.html
26 *
27 * This library is free software; you can redistribute it and/or
28 * modify it under the terms of the GNU Lesser General Public
29 * License as published by the Free Software Foundation; either
30 * version 2 of the License, or (at your option) any later version.
31 *
32 * This library is distributed in the hope that it will be useful,
33 * but WITHOUT ANY WARRANTY; without even the implied warranty of
34 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
35 * Lesser General Public License for more details.
36 *
37 * You should have received a copy of the GNU Lesser General Public
38 * License along with this library in the file COPYING.LIB;
39 * if not, write to the Free Software Foundation, Inc.,
40 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
41 */
42
43 #include "pthread.h"
44 #include "implement.h"
45
46
47 int
pthread_mutexattr_getpshared(const pthread_mutexattr_t * attr,int * pshared)48 pthread_mutexattr_getpshared (const pthread_mutexattr_t * attr, int *pshared)
49 /*
50 * ------------------------------------------------------
51 * DOCPUBLIC
52 * Determine whether mutexes created with 'attr' can be
53 * shared between processes.
54 *
55 * PARAMETERS
56 * attr
57 * pointer to an instance of pthread_mutexattr_t
58 *
59 * pshared
60 * will be set to one of:
61 *
62 * PTHREAD_PROCESS_SHARED
63 * May be shared if in shared memory
64 *
65 * PTHREAD_PROCESS_PRIVATE
66 * Cannot be shared.
67 *
68 *
69 * DESCRIPTION
70 * Mutexes creatd with 'attr' can be shared between
71 * processes if pthread_mutex_t variable is allocated
72 * in memory shared by these processes.
73 * NOTES:
74 * 1) pshared mutexes MUST be allocated in shared
75 * memory.
76 * 2) The following macro is defined if shared mutexes
77 * are supported:
78 * _POSIX_THREAD_PROCESS_SHARED
79 *
80 * RESULTS
81 * 0 successfully retrieved attribute,
82 * EINVAL 'attr' is invalid,
83 *
84 * ------------------------------------------------------
85 */
86 {
87 int result;
88
89 if ((attr != NULL && *attr != NULL) && (pshared != NULL))
90 {
91 *pshared = (*attr)->pshared;
92 result = 0;
93 }
94 else
95 {
96 result = EINVAL;
97 }
98
99 return (result);
100
101 } /* pthread_mutexattr_getpshared */
102