xref: /openbsd-src/lib/libpthread/man/pthread_rwlockattr_getpshared.3 (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1.\" $OpenBSD: pthread_rwlockattr_getpshared.3,v 1.6 2000/04/12 21:48:03 aaron Exp $
2.\" Copyright (c) 1998 Alex Nash
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
11.\"    notice, this list of conditions and the following disclaimer in the
12.\"    documentation and/or other materials provided with the distribution.
13.\"
14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24.\" SUCH DAMAGE.
25.\"
26.\" $FreeBSD: pthread_rwlockattr_getpshared.3,v 1.4 1999/08/28 00:03:10 peter Exp $
27.\"
28.Dd March 22, 1999
29.Dt PTHREAD_RWLOCKATTR_GETPSHARED 3
30.Os
31.Sh NAME
32.Nm pthread_rwlockattr_getpshared
33.Nd get the process shared attribute
34.Sh SYNOPSIS
35.Fd #include <pthread.h>
36.Ft int
37.Fn pthread_rwlockattr_getpshared "const pthread_rwlockattr_t *attr" "int *pshared"
38.Sh DESCRIPTION
39The
40.Fn pthread_rwlockattr_getpshared
41function is used to get the process shared setting of a read/write
42lock attribute object.  The setting is returned via
43.Fa pshared ,
44and may be one of two values:
45.Bl -hang -offset flag -width 123456789012345678901234
46.It Ar PTHREAD_PROCESS_SHARED
47Any thread of any process that has access to the memory where the
48read/write lock resides can manipulate the lock.
49.It Ar PTHREAD_PROCESS_PRIVATE
50Only threads created within the same process as the thread that
51initialized the read/write lock can manipulate the lock.  This is
52the default value.
53.El
54.Sh RETURN VALUES
55If successful, the
56.Fn pthread_rwlockattr_getpshared
57function will return zero.  Otherwise an error number will be returned
58to indicate the error.
59.Sh SEE ALSO
60.Xr pthread_rwlock_init 3 ,
61.Xr pthread_rwlockattr_init 3 ,
62.Xr pthread_rwlockattr_setpshared 3
63.Sh STANDARDS
64The
65.Fn pthread_rwlockattr_getpshared
66function is expected to conform to
67.St -susv2 .
68.Sh ERRORS
69.Fn pthread_rwlockattr_getpshared
70may fail if:
71.Bl -tag -width Er
72.It Bq Er EINVAL
73The value specified by
74.Fa attr
75is invalid.
76.El
77.Sh HISTORY
78The
79.Fn pthread_rwlockattr_getpshared
80function first appeared in
81.Fx 3.0
82and
83.Ox 2.5 .
84