.\" $NetBSD: pthread_attr.3,v 1.22 2012/11/10 23:12:36 uwe Exp $ .\" .\" Copyright (c) 2002, 2010 The NetBSD Foundation, Inc. .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS .\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED .\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS .\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .\" Copyright (C) 2000 Jason Evans . .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice(s), this list of conditions and the following disclaimer as .\" the first lines of this file unmodified other than the possible .\" addition of one or more copyright notices. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice(s), this list of conditions and the following disclaimer in .\" the documentation and/or other materials provided with the .\" distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY .\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR .\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR .\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, .\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE .\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, .\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. .\" .\" $FreeBSD: src/lib/libpthread/man/pthread_attr.3,v 1.11 2002/09/16 19:29:28 mini Exp $ .\" .Dd July 9, 2010 .Dt PTHREAD_ATTR 3 .Os .Sh NAME .Nm pthread_attr_init , .Nm pthread_attr_destroy .Nd thread attribute operations .Sh LIBRARY .Lb libpthread .Sh SYNOPSIS .In pthread.h .Ft int .Fn pthread_attr_init "pthread_attr_t *attr" .Ft int .Fn pthread_attr_destroy "pthread_attr_t *attr" .Sh DESCRIPTION Thread attributes are used to specify parameters to .Fn pthread_create . One attribute object can be used in multiple calls to .Fn pthread_create , with or without modifications between the calls. The .Vt pthread_attr_t type is an opaque representation of the thread attributes; any access to the object other than via the described .Fn pthread_attr_* functions may result in undefined behavior. .Pp The .Fn pthread_attr_init function initializes .Fa attr with the default thread attributes used in the implementation. Depending on the implementation, undefined behavior may follow if an uninitialized thread attribute object is used with some of the thread attribute functions. It is therefore a good practice to always use .Fn pthread_attr_init , even if this might be unnecessary. Undefined behavior may also follow if an already initialized .Fa attr is used with .Fn pthread_attr_init . .Pp When the attribute object is no longer needed, it should be destroyed by using .Fn pthread_attr_destroy . The function has no effect on threads that were created by using a given attribute object. A destroyed .Fa attr can be reinitialized using .Fn pthread_attr_init , but all other actions with the destroyed object are unspecified. .Pp The following standard thread attribute functions are available: .Bl -column -offset indent "pthread_attr_getinheritsched " "XXX" .It Sy Function Ta Sy Description .It Xr pthread_attr_getdetachstate 3 Ta thread detach state .It Xr pthread_attr_getguardsize 3 Ta thread guard size .It Xr pthread_attr_getinheritsched 3 Ta inherit scheduler attribute .It Xr pthread_attr_getschedparam 3 Ta thread scheduling parameter .It Xr pthread_attr_getschedpolicy 3 Ta thread scheduling policy .It Xr pthread_attr_getscope 3 Ta thread contention scope .It Xr pthread_attr_getstack 3 Ta thread stack .It Xr pthread_attr_getstacksize 3 Ta thread stack size .It Xr pthread_attr_getstackaddr 3 Ta thread stack address .El .Pp Each listed .Fn pthread_attr_get* function has a .Fn pthread_attr_set* counterpart. In addition, the following .Nx specific extensions are available: .Bl -column -offset indent "pthread_attr_getinheritsched " "XXX" .It Sy Function Ta Sy Description .It Xr pthread_attr_get_np 3 Ta attributes of a running thread .It Xr pthread_attr_getname_np 3 Ta descriptive name of an attribute .El .Sh RETURN VALUES If successful, these functions return 0. Otherwise, an error number is returned to indicate the error. .Sh ERRORS No errors are defined for .Fn pthread_attr_init and .Fn pthread_attr_destroy . .Sh SEE ALSO .Xr pthread_create 3 , .Xr pthread_join 3 .Sh STANDARDS Both .Fn pthread_attr_init and .Fn pthread_attr_destroy conform to .St -p1003.1-2001 .