1.\" $OpenBSD: pthread_getspecific.3,v 1.4 1999/11/24 05:35:32 d Exp $ 2.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>. 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.\" 3. All advertising materials mentioning features or use of this software 14.\" must display the following acknowledgement: 15.\" This product includes software developed by John Birrell. 16.\" 4. Neither the name of the author nor the names of any co-contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" $FreeBSD: pthread_getspecific.3,v 1.6 1999/08/28 00:03:06 peter 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