xref: /freebsd/share/man/man3/pthread_rwlockattr_getpshared.3 (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
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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.Fn pthread_rwlockattr_getpshared "const pthread_rwlockattr_t *restrict attr" "int *restrict pshared"
39.Sh DESCRIPTION
40The
41.Fn pthread_rwlockattr_getpshared
42function is used to get the process shared setting of a read/write
43lock attribute object.
44The setting is returned via
45.Fa pshared ,
46and may be one of two values:
47.Bl -tag -width PTHREAD_PROCESS_PRIVATE
48.It Dv PTHREAD_PROCESS_SHARED
49Any thread of any process that has access to the memory where the
50read/write lock resides can manipulate the lock.
51.It Dv PTHREAD_PROCESS_PRIVATE
52Only threads created within the same process as the thread that
53initialized the read/write lock can manipulate the lock.
54This is
55the default value.
56.El
57.Sh RETURN VALUES
58If successful, the
59.Fn pthread_rwlockattr_getpshared
60function will return zero.
61Otherwise an error number will be returned
62to indicate the error.
63.Sh ERRORS
64The
65.Fn pthread_rwlockattr_getpshared
66function may fail if:
67.Bl -tag -width Er
68.It Bq Er EINVAL
69The value specified by
70.Fa attr
71is invalid.
72.El
73.Sh SEE ALSO
74.Xr pthread_rwlock_init 3 ,
75.Xr pthread_rwlockattr_init 3 ,
76.Xr pthread_rwlockattr_setpshared 3
77.Sh STANDARDS
78The
79.Fn pthread_rwlockattr_getpshared
80function is expected to conform to
81.St -susv2 .
82.Sh HISTORY
83The
84.Fn pthread_rwlockattr_getpshared
85function first appeared in
86.Fx 3.0 .
87