xref: /illumos-gate/usr/src/man/man3head/sched.h.3head (revision 30165b7f6753bc3d48c52319bed7ec7b3ea36b3c)

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 SunOS 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]


Copyright (c) 1992, X/Open Company Limited All Rights Reserved
Portions Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved.

SCHED.H 3HEAD "Apr 1, 2008"
NAME
sched.h, sched - execution scheduling
SYNOPSIS

#include <sched.h>
DESCRIPTION

The <sched.h> header defines the sched_param structure, which contains the scheduling parameters required for implementation of each supported scheduling policy. This structure contains the following member:

int sched_priority process execution scheduling priority

Each process is controlled by an associated scheduling policy and priority. Associated with each policy is a priority range. Each policy definition specifies the minimum priority range for that policy. The priority ranges for each policy may overlap the priority ranges of other policies.

The scheduling policies are indicated by the values of the following symbolic constants: SCHED_OTHER

Processes are scheduled according to the traditional Time-Sharing Class (TS) policy as described in priocntl(2).

SCHED_FIFO

Processes are scheduled in the Real-Time (RT) scheduling class, according to the First-In-First-Out (FIFO) policy. Processes scheduled to this policy, if not preempted by a higher priority or interrupted by a signal, will proceed until completion.

SCHED_RR

Processes are scheduled in the Real-Time (RT) scheduling class, according to the Round-Robin (RR) policy. Processes scheduled to this policy, if not preempted by a higher priority or interrupted by a signal, will execute for a time period, returned by sched_rr_get_interval(3C) or by the system.

SCHED_IA

Processes are scheduled according to the Inter-Active Class (IA) policy as described in priocntl(2).

SCHED_FSS

Processes are scheduled according to the Fair-Share Class (FSS) policy as described in priocntl(2).

SCHED_FX

Processes are scheduled according to the Fixed-Priority Class (FX) policy as described in priocntl(2).

The values of these constants are distinct.

Inclusion of the <sched.h> header will make visible symbols defined in the header <time.h>.

SEE ALSO

priocntl(2), sched_get_priority_max(3C), sched_get_priority_min(3C), sched_rr_get_interval(3C), time.h(3HEAD)