xref: /freebsd/share/man/man3/pthread_setspecific.3 (revision 0f7d684755aefbcfd70b45d24efc2d39bc505c4c)
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.\"
310f7d6847SJulian Elischer.Dd April 4, 1996
320f7d6847SJulian Elischer.Dt PTHREAD_SETSPECIFIC 3
330f7d6847SJulian Elischer.Os BSD 4
340f7d6847SJulian Elischer.Sh NAME
350f7d6847SJulian Elischer.Nm pthread_setspecific
360f7d6847SJulian Elischer.Nd set a thread-specific data value
370f7d6847SJulian Elischer.Sh SYNOPSIS
380f7d6847SJulian Elischer.Fd #include <pthread.h>
390f7d6847SJulian Elischer.Ft int
400f7d6847SJulian Elischer.Fn pthread_setspecific "pthread_key_t key" "const void *value"
410f7d6847SJulian Elischer.Sh DESCRIPTION
420f7d6847SJulian ElischerThe
430f7d6847SJulian Elischer.Fn pthread_setspecific
440f7d6847SJulian Elischerfunction associates a thread-specific value with a
450f7d6847SJulian Elischer.Fa key
460f7d6847SJulian Elischerobtained via a previous call to
470f7d6847SJulian Elischer.Fn pthread_key_create .
480f7d6847SJulian ElischerDifferent threads man bind different values to the same key. These values are
490f7d6847SJulian Elischertypically pointers to blocks of dynamically allocated memory that have been
500f7d6847SJulian Elischerreserved for use by the calling thread.
510f7d6847SJulian Elischer.Pp
520f7d6847SJulian ElischerThe effect of calling
530f7d6847SJulian Elischer.Fn pthread_setspecific
540f7d6847SJulian Elischerwith a key value not obtained from
550f7d6847SJulian Elischer.Fn pthread_key_create
560f7d6847SJulian Elischeror after
570f7d6847SJulian Elischer.Fa key
580f7d6847SJulian Elischerhas been deleted with
590f7d6847SJulian Elischer.Fn pthread_key_delete
600f7d6847SJulian Elischeris undefined.
610f7d6847SJulian Elischer.Pp
620f7d6847SJulian Elischer.Fn pthread_setspecific
630f7d6847SJulian Elischermay be called from a thread-specific data destructor function, however this
640f7d6847SJulian Elischermay result in lost storage or infinite loops.
650f7d6847SJulian Elischer.Sh RETURN VALUES
660f7d6847SJulian ElischerIf successful,  the
670f7d6847SJulian Elischer.Fn pthread_setspecific
680f7d6847SJulian Elischerfunction will return zero. Otherwise an error number will be returned to
690f7d6847SJulian Elischerindicate the error.
700f7d6847SJulian Elischer.Sh ERRORS
710f7d6847SJulian Elischer.Fn pthread_setspecific
720f7d6847SJulian Elischerwill fail if:
730f7d6847SJulian Elischer.Bl -tag -width Er
740f7d6847SJulian Elischer.It Bq Er ENOMEM
750f7d6847SJulian ElischerInsufficient memory exists to associate the value with the
760f7d6847SJulian Elischer.Fa key .
770f7d6847SJulian Elischer.It Bq Er EINVAL
780f7d6847SJulian ElischerThe
790f7d6847SJulian Elischer.Fa key
800f7d6847SJulian Elischervalue is invalid.
810f7d6847SJulian Elischer.El
820f7d6847SJulian Elischer.Pp
830f7d6847SJulian Elischer.Sh SEE ALSO
840f7d6847SJulian Elischer.Xr pthread_key_create 3 ,
850f7d6847SJulian Elischer.Xr pthread_key_delete 3 ,
860f7d6847SJulian Elischer.Xr pthread_getspecific 3
870f7d6847SJulian Elischer.Sh STANDARDS
880f7d6847SJulian Elischer.Fn pthread_setspecific
890f7d6847SJulian Elischeris expected to conform to IEEE
900f7d6847SJulian Elischer.Pq Dq Tn POSIX
910f7d6847SJulian ElischerStd 1003.1c when it is published.
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