xref: /titanic_44/usr/src/man/man3c/pthread_getschedparam.3c (revision 427a21b56415a2c5048627d491e6e8da8d953bf1)
te
Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved.
Copyright (c) 2001, the Institute of Electrical and Electronics Engineers, Inc. and The Open Group. All Rights Reserved.
Copyright 1991, 1992, 1994, The X/Open Company Ltd.
Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
http://www.opengroup.org/bookstore/.
The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
This notice shall appear on any product containing this material.
The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
PTHREAD_GETSCHEDPARAM 3C "Apr 1, 2008"
NAME
pthread_getschedparam, pthread_setschedparam - access dynamic thread scheduling parameters
SYNOPSIS

cc -mt [ flag... ] file... -lpthread [ library... ]
#include <pthread.h>

int pthread_getschedparam(pthread_t thread, int *restrict policy,
 struct sched_param *restrict param);

int pthread_setschedparam(pthread_t thread, int policy,
 const struct sched_param *param);
DESCRIPTION

The pthread_getschedparam() and pthread_setschedparam() functions allow the scheduling policy and scheduling parameters of individual threads within a multithreaded process to be retrieved and set. Supported policies are : SCHED_OTHER

traditional time-sharing scheduling class

SCHED_FIFO

real-time class: run to completion

SCHED_RR

real-time class: round-robin

SCHED_IA

interactive time-sharing class

SCHED_FSS

fair-share scheduling class

SCHED_FX

fixed priority scheduling class

See pthreads(5). The affected scheduling parameter is the sched_priority member of the sched_param structure.

The pthread_getschedparam() function retrieves the scheduling policy and scheduling parameters for the thread whose thread ID is given by thread and stores those values in policy and param, respectively. The priority value returned from pthread_getschedparam() is the value specified by the most recent pthread_setschedparam() or pthread_create() call affecting the target thread, and does not reflect any temporary adjustments to its priority as a result of any priority inheritance or ceiling functions. The pthread_setschedparam() function sets the scheduling policy and associated scheduling parameters for the thread whose thread ID is given by thread to the policy and associated parameters provided in policy and param, respectively.

If the pthread_setschedparam() function fails, no scheduling parameters will be changed for the target thread.

RETURN VALUES

If successful, the pthread_getschedparam() and pthread_setschedparam() functions return 0. Otherwise, an error number is returned to indicate the error.

ERRORS

The pthread_getschedparam() and pthread_gsetschedparam() functions will fail if: ESRCH

The value specified by thread does not refer to an existing thread.

The pthread_setschedparam() function will fail if: EINVAL

The value specified by policy or one of the scheduling parameters associated with the scheduling policy policy is invalid.

EPERM

The caller does not have the appropriate permission to set either the scheduling parameters or the scheduling policy of the specified thread.

ATTRIBUTES

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE
Interface Stability Committed
MT-Level MT-Safe
Standard See standards(5).
SEE ALSO

pthread_attr_init(3C), sched_getparam(3C), sched_get_priority_max(3C)sched_get_priority_max(3C), sched_get_priority_min(3C), sched_setparam(3C), sched_getscheduler(3C), sched_setscheduler(3C), attributes(5), pthreads(5), standards(5)