1.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by John Birrell. 15.\" 4. Neither the name of the author nor the names of any co-contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" $FreeBSD$ 32.\" 33.Dd April 4, 1996 34.Dt PTHREAD_GETSPECIFIC 3 35.Os 36.Sh NAME 37.Nm pthread_getspecific 38.Nd get a thread-specific data value 39.Sh LIBRARY 40.Lb libpthread 41.Sh SYNOPSIS 42.In pthread.h 43.Ft void * 44.Fn pthread_getspecific "pthread_key_t key" 45.Sh DESCRIPTION 46The 47.Fn pthread_getspecific 48function returns the value currently bound to the specified 49.Fa key 50on behalf of the calling thread. 51.Pp 52The effect of calling 53.Fn pthread_getspecific 54with a 55.Fa key 56value not obtained from 57.Fn pthread_key_create 58or after 59.Fa key 60has been deleted with 61.Fn pthread_key_delete 62is undefined. 63.Pp 64The 65.Fn pthread_getspecific 66function may be called from a thread-specific data destructor function. 67A call to 68.Fn pthread_getspecific 69for the thread-specific data key being destroyed returns the value NULL, 70unless the value is changed (after the destructor starts) by a call to 71.Fn pthread_setspecific . 72.Sh RETURN VALUES 73The 74.Fn pthread_getspecific 75function will return the thread-specific data value associated with the given 76.Fa key . 77If no thread-specific data value is associated with 78.Fa key , 79then the value NULL is returned. 80.Sh ERRORS 81None. 82.Sh SEE ALSO 83.Xr pthread_key_create 3 , 84.Xr pthread_key_delete 3 , 85.Xr pthread_setspecific 3 86.Sh STANDARDS 87The 88.Fn pthread_getspecific 89function conforms to 90.St -p1003.1-96 . 91