Libc-583.tar.gz

[apple/libc.git] / gen / FreeBSD / nice.3

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.\"     @(#)nice.3	8.1 (Berkeley) 6/4/93
.\" $FreeBSD: src/lib/libc/gen/nice.3,v 1.11 2001/10/01 16:08:51 ru Exp $
.\"
.Dd June 4, 1993
.Dt NICE 3
.Os
.Sh NAME
.Nm nice
.Nd set program scheduling priority
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In 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 SEE ALSO
.Xr nice 1 ,
.Xr fork 2 ,
.Xr setpriority 2 ,
.Xr renice 8
.Sh HISTORY
A
.Fn nice
syscall appeared in
.At v6 .