98 lines
3.1 KiB
Groff
98 lines
3.1 KiB
Groff
.\" $NetBSD: nice.3,v 1.9 2001/09/16 02:57:04 wiz Exp $
|
|
.\"
|
|
.\" Copyright (c) 1980, 1991, 1993
|
|
.\" The Regents of the University of California. 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.
|
|
.\" 3. All advertising materials mentioning features or use of this software
|
|
.\" must display the following acknowledgement:
|
|
.\" This product includes software developed by the University of
|
|
.\" California, Berkeley and its contributors.
|
|
.\" 4. Neither the name of the University nor the names of its contributors
|
|
.\" may be used to endorse or promote products derived from this software
|
|
.\" without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
|
|
.\"
|
|
.\" @(#)nice.3 8.1 (Berkeley) 6/4/93
|
|
.\"
|
|
.Dd February 16, 1998
|
|
.Dt NICE 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm nice
|
|
.Nd set program scheduling priority
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.Fd #include <unistd.h>
|
|
.Ft int
|
|
.Fn nice "int incr"
|
|
.Sh DESCRIPTION
|
|
.Bf -symbolic
|
|
This interface is obsoleted by
|
|
.Xr setpriority 2 .
|
|
.Ef
|
|
.Pp
|
|
The
|
|
.Fn nice
|
|
function obtains the scheduling priority of the process
|
|
from the system and sets it to the priority value specified in
|
|
.Fa incr .
|
|
The priority is a value in the range -20 to 20.
|
|
The default priority is 0; lower priorities cause more favorable scheduling.
|
|
Only the super-user may lower priorities.
|
|
.Pp
|
|
Children inherit the priority of their parent processes via
|
|
.Xr fork 2 .
|
|
.Sh RETURN VALUES
|
|
Upon successful completition,
|
|
.Fn nice
|
|
returns the new nice value minus
|
|
.Dv NZERO .
|
|
Otherwise, -1 is returned, the process' nice value is not changed, and
|
|
.Va errno
|
|
is set to indicate the error.
|
|
.Sh ERRORS
|
|
The
|
|
.Fn nice
|
|
function will fail if:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EPERM
|
|
The
|
|
.Fa incr
|
|
argument is negative and the caller is not the super-user.
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr nice 1 ,
|
|
.Xr fork 2 ,
|
|
.Xr setpriority 2 ,
|
|
.Xr renice 8
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn nice
|
|
function conforms to
|
|
.St -xpg4.2 .
|
|
.Sh HISTORY
|
|
A
|
|
.Fn nice
|
|
syscall appeared in
|
|
.At v6 .
|