xref: /openbsd-src/lib/libpthread/man/pthread_getspecific.3 (revision 62a742911104f98b9185b2c6b6007d9b1c36396c)
1.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
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31.\"	$FreeBSD: pthread_getspecific.3,v 1.5 1998/08/03 00:58:36 alex Exp $
32.\"	$OpenBSD: pthread_getspecific.3,v 1.3 1999/03/10 10:04:42 d Exp $
33.\"
34.Dd April 4, 1996
35.Dt PTHREAD_GETSPECIFIC 3
36.Os
37.Sh NAME
38.Nm pthread_getspecific
39.Nd get a thread-specific data value
40.Sh SYNOPSIS
41.Fd #include <pthread.h>
42.Ft void *
43.Fn pthread_getspecific "pthread_key_t key"
44.Sh DESCRIPTION
45The
46.Fn pthread_getspecific
47function returns the value currently bound to the specified
48.Fa key
49on behalf of the calling thread.
50.Pp
51The effect of calling
52.Fn pthread_getspecific
53with a
54.Fa key
55value not obtained from
56.Fn pthread_key_create
57or after
58.Fa key
59has been deleted with
60.Fn pthread_key_delete
61is undefined.
62.Pp
63.Fn pthread_getspecific
64may be called from a thread-specific data destructor function.
65.Sh RETURN VALUES
66The
67.Fn pthread_getspecific
68function will return the thread-specific data value associated with the given
69.Fa key .
70If no thread-specific data value is associated with
71.Fa key ,
72then the value NULL is returned.
73.Sh ERRORS
74None.
75.Sh SEE ALSO
76.Xr pthread_key_create 3 ,
77.Xr pthread_key_delete 3 ,
78.Xr pthread_setspecific 3
79.Sh STANDARDS
80.Fn pthread_getspecific
81conforms to ISO/IEC 9945-1 ANSI/IEEE
82.Pq Dq Tn POSIX
83Std 1003.1 Second Edition 1996-07-12.
84