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.Dd April 4, 1996 32.Dt PTHREAD_GETSPECIFIC 3 33.Os 34.Sh NAME 35.Nm pthread_getspecific 36.Nd get a thread-specific data value 37.Sh LIBRARY 38.Lb libpthread 39.Sh SYNOPSIS 40.In pthread.h 41.Ft void * 42.Fn pthread_getspecific "pthread_key_t key" 43.Sh DESCRIPTION 44The 45.Fn pthread_getspecific 46function returns the value currently bound to the specified 47.Fa key 48on behalf of the calling thread. 49.Pp 50The effect of calling 51.Fn pthread_getspecific 52with a 53.Fa key 54value not obtained from 55.Fn pthread_key_create 56or after 57.Fa key 58has been deleted with 59.Fn pthread_key_delete 60is undefined. 61.Pp 62The 63.Fn pthread_getspecific 64function may be called from a thread-specific data destructor function. 65A call to 66.Fn pthread_getspecific 67for the thread-specific data key being destroyed returns the value NULL, 68unless the value is changed (after the destructor starts) by a call to 69.Fn pthread_setspecific . 70.Sh RETURN VALUES 71The 72.Fn pthread_getspecific 73function will return the thread-specific data value associated with the given 74.Fa key . 75If no thread-specific data value is associated with 76.Fa key , 77then the value NULL is returned. 78.Sh ERRORS 79None. 80.Sh SEE ALSO 81.Xr pthread_key_create 3 , 82.Xr pthread_key_delete 3 , 83.Xr pthread_setspecific 3 84.Sh STANDARDS 85The 86.Fn pthread_getspecific 87function conforms to 88.St -p1003.1-96 . 89