1.\" Copyright (c) 1998 Alex Nash
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25.\" $FreeBSD$
26.\"
27.Dd August 17, 2018
28.Dt PTHREAD_RWLOCKATTR_GETPSHARED 3
29.Os
30.Sh NAME
31.Nm pthread_rwlockattr_getpshared
32.Nd get the process shared attribute
33.Sh LIBRARY
34.Lb libpthread
35.Sh SYNOPSIS
36.In pthread.h
37.Ft int
38.Fo pthread_rwlockattr_getpshared
39.Fa "const pthread_rwlockattr_t *restrict attr" "int *restrict pshared"
40.Fc
41.Sh DESCRIPTION
42The
43.Fn pthread_rwlockattr_getpshared
44function is used to get the process shared setting of a read/write
45lock attribute object.
46The setting is returned via
47.Fa pshared ,
48and may be one of two values:
49.Bl -tag -width PTHREAD_PROCESS_PRIVATE
50.It Dv PTHREAD_PROCESS_SHARED
51Any thread of any process that has access to the memory where the
52read/write lock resides can manipulate the lock.
53.It Dv PTHREAD_PROCESS_PRIVATE
54Only threads created within the same process as the thread that
55initialized the read/write lock can manipulate the lock.
56This is
57the default value.
58.El
59.Sh RETURN VALUES
60If successful, the
61.Fn pthread_rwlockattr_getpshared
62function will return zero.
63Otherwise an error number will be returned
64to indicate the error.
65.Sh ERRORS
66The
67.Fn pthread_rwlockattr_getpshared
68function may fail if:
69.Bl -tag -width Er
70.It Bq Er EINVAL
71The value specified by
72.Fa attr
73is invalid.
74.El
75.Sh SEE ALSO
76.Xr pthread_rwlock_init 3 ,
77.Xr pthread_rwlockattr_init 3 ,
78.Xr pthread_rwlockattr_setpshared 3
79.Sh STANDARDS
80The
81.Fn pthread_rwlockattr_getpshared
82function is expected to conform to
83.St -susv2 .
84.Sh HISTORY
85The
86.Fn pthread_rwlockattr_getpshared
87function first appeared in
88.Fx 3.0 .
89