.\" Copyright (c) 1980 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"	@(#)nice.3c	6.1 (Berkeley) 5/9/85
.\"
.TH NICE 2 "May 9, 1985"
.UC 4
.SH NAME
nice \- set program priority
.SH SYNOPSIS
.nf
.ft B
#include <unistd.h>

int nice(int \fIincr\fP)
.ft R
.fi
.SH DESCRIPTION
The scheduling
priority of the process is augmented by
.IR incr .
Positive priorities get less
service than normal.
Priority 10 is recommended to users
who wish to execute long-running programs
without flak from the administration.
.PP
Negative increments are ignored except on behalf of 
the super-user.
The priority is limited to the range
\-20 (most urgent) to 20 (least).
.PP
The priority of a process is
passed to a child process by
.BR fork (2).
For a privileged process to return to normal priority
from an unknown state,
.B nice
should be called successively with arguments
\-40 (goes to priority \-20 because of truncation),
20 (to get to 0).
.PP
If a CPU-bound process at nice level 0 gets one tick from the scheduler,
then a CPU-bound process at nice level
.I n
is entitled to 2\ **\ (\-\fIn\fP\ /\ 2) ticks, which boils down to
1/32 ticks at nice level 10, and 1/1024 ticks at nice level 20.
Compared to other systems the effect of the Minix nice is quite strong.
.SH "SEE ALSO"
.BR nice (1).