xref: /freebsd/share/man/man3/pthread_setspecific.3 (revision c6ff3a1bf74d96278726113478b2c66884aab584)
10f7d6847SJulian Elischer.\" Copyright (c) 1996 John Birrell <jb@cimlogic.com.au>.
20f7d6847SJulian Elischer.\" All rights reserved.
30f7d6847SJulian Elischer.\"
40f7d6847SJulian Elischer.\" Redistribution and use in source and binary forms, with or without
50f7d6847SJulian Elischer.\" modification, are permitted provided that the following conditions
60f7d6847SJulian Elischer.\" are met:
70f7d6847SJulian Elischer.\" 1. Redistributions of source code must retain the above copyright
80f7d6847SJulian Elischer.\"    notice, this list of conditions and the following disclaimer.
90f7d6847SJulian Elischer.\" 2. Redistributions in binary form must reproduce the above copyright
100f7d6847SJulian Elischer.\"    notice, this list of conditions and the following disclaimer in the
110f7d6847SJulian Elischer.\"    documentation and/or other materials provided with the distribution.
120f7d6847SJulian Elischer.\" 3. All advertising materials mentioning features or use of this software
130f7d6847SJulian Elischer.\"    must display the following acknowledgement:
140f7d6847SJulian Elischer.\"	This product includes software developed by John Birrell.
150f7d6847SJulian Elischer.\" 4. Neither the name of the author nor the names of any co-contributors
160f7d6847SJulian Elischer.\"    may be used to endorse or promote products derived from this software
170f7d6847SJulian Elischer.\"    without specific prior written permission.
180f7d6847SJulian Elischer.\"
190f7d6847SJulian Elischer.\" THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
200f7d6847SJulian Elischer.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
210f7d6847SJulian Elischer.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
220f7d6847SJulian Elischer.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
230f7d6847SJulian Elischer.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
240f7d6847SJulian Elischer.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
250f7d6847SJulian Elischer.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
260f7d6847SJulian Elischer.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
270f7d6847SJulian Elischer.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
280f7d6847SJulian Elischer.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
290f7d6847SJulian Elischer.\" SUCH DAMAGE.
300f7d6847SJulian Elischer.\"
317f3dea24SPeter Wemm.\" $FreeBSD$
32fbc400a6SNik Clayton.\"
330f7d6847SJulian Elischer.Dd April 4, 1996
340f7d6847SJulian Elischer.Dt PTHREAD_SETSPECIFIC 3
350f7d6847SJulian Elischer.Os BSD 4
360f7d6847SJulian Elischer.Sh NAME
370f7d6847SJulian Elischer.Nm pthread_setspecific
380f7d6847SJulian Elischer.Nd set a thread-specific data value
390f7d6847SJulian Elischer.Sh SYNOPSIS
400f7d6847SJulian Elischer.Fd #include <pthread.h>
410f7d6847SJulian Elischer.Ft int
420f7d6847SJulian Elischer.Fn pthread_setspecific "pthread_key_t key" "const void *value"
430f7d6847SJulian Elischer.Sh DESCRIPTION
440f7d6847SJulian ElischerThe
450f7d6847SJulian Elischer.Fn pthread_setspecific
460f7d6847SJulian Elischerfunction associates a thread-specific value with a
470f7d6847SJulian Elischer.Fa key
480f7d6847SJulian Elischerobtained via a previous call to
490f7d6847SJulian Elischer.Fn pthread_key_create .
50c6ff3a1bSSheldon HearnDifferent threads man bind different values to the same key.
51c6ff3a1bSSheldon HearnThese values are
520f7d6847SJulian Elischertypically pointers to blocks of dynamically allocated memory that have been
530f7d6847SJulian Elischerreserved for use by the calling thread.
540f7d6847SJulian Elischer.Pp
550f7d6847SJulian ElischerThe effect of calling
560f7d6847SJulian Elischer.Fn pthread_setspecific
570f7d6847SJulian Elischerwith a key value not obtained from
580f7d6847SJulian Elischer.Fn pthread_key_create
590f7d6847SJulian Elischeror after
600f7d6847SJulian Elischer.Fa key
610f7d6847SJulian Elischerhas been deleted with
620f7d6847SJulian Elischer.Fn pthread_key_delete
630f7d6847SJulian Elischeris undefined.
640f7d6847SJulian Elischer.Pp
650f7d6847SJulian Elischer.Fn pthread_setspecific
660f7d6847SJulian Elischermay be called from a thread-specific data destructor function, however this
670f7d6847SJulian Elischermay result in lost storage or infinite loops.
680f7d6847SJulian Elischer.Sh RETURN VALUES
690f7d6847SJulian ElischerIf successful,  the
700f7d6847SJulian Elischer.Fn pthread_setspecific
71c6ff3a1bSSheldon Hearnfunction will return zero.
72c6ff3a1bSSheldon HearnOtherwise an error number will be returned to
730f7d6847SJulian Elischerindicate the error.
740f7d6847SJulian Elischer.Sh ERRORS
750f7d6847SJulian Elischer.Fn pthread_setspecific
760f7d6847SJulian Elischerwill fail if:
770f7d6847SJulian Elischer.Bl -tag -width Er
780f7d6847SJulian Elischer.It Bq Er ENOMEM
790f7d6847SJulian ElischerInsufficient memory exists to associate the value with the
800f7d6847SJulian Elischer.Fa key .
810f7d6847SJulian Elischer.It Bq Er EINVAL
820f7d6847SJulian ElischerThe
830f7d6847SJulian Elischer.Fa key
840f7d6847SJulian Elischervalue is invalid.
850f7d6847SJulian Elischer.El
860f7d6847SJulian Elischer.Pp
870f7d6847SJulian Elischer.Sh SEE ALSO
8875141cc9SWolfram Schneider.Xr pthread_getspecific 3 ,
890f7d6847SJulian Elischer.Xr pthread_key_create 3 ,
9075141cc9SWolfram Schneider.Xr pthread_key_delete 3
910f7d6847SJulian Elischer.Sh STANDARDS
920f7d6847SJulian Elischer.Fn pthread_setspecific
938ac3b85eSAlexander Langerconforms to ISO/IEC 9945-1 ANSI/IEEE
940f7d6847SJulian Elischer.Pq Dq Tn POSIX
958ac3b85eSAlexander LangerStd 1003.1 Second Edition 1996-07-12.
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