freebsd-dev/usr.bin/nice/nice.1

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.\" @(#)nice.1 8.1 (Berkeley) 6/6/93
.\" $FreeBSD$
.\"
.Dd June 6, 1993
.Dt NICE 1
.Os BSD 4
.Sh NAME
.Nm nice
.Nd execute a command at a low scheduling priority
.Sh SYNOPSIS
.Nm
.Op Fl Ns Ar number
.Ar command
.Op Ar arguments
.Sh DESCRIPTION
.Nm Nice
runs
.Ar command
at a low priority.
(Think of low and slow).
If
.Fl Ns Ar number
is not given,
.Nm
assumes the value 10.
The priority is a value in the range -20 to 20.
The default priority is 0, priority 20 is the lowest possible.
.Nm Nice
will execute
.Ar command
at priority
.Ar number
relative to the priority
of
.Nm .
Higher priorities than the
current process priority can only requested by the
super-user.
Negative numbers are expressed as
.Fl - Ns Ar number .
.Pp
The returned exit status is the exit value from the
command executed by
.Nm .
.Pp
Some shells may provide a builtin
.Nm
command which is similar or identical to this utility.
Consult the
.Xr builtin 1
manual page.
.Sh EXAMPLES
$ nice -5 date
.Pp
Execute command
.Sq date
at priority 5 assuming the priority of the
shell is 0.
.Pp
# nice -16 nice --35 date
.Pp
Execute command
.Sq date
at priority -19 assuming the priority of the
shell is 0 and you are the super-user.
.Sh SEE ALSO
.Xr builtin 1 ,
.Xr csh 1 ,
.Xr idprio 1 ,
.Xr rtprio 1 ,
.Xr getpriority 2 ,
.Xr setpriority 2 ,
.Xr renice 8
.Sh HISTORY
A
.Nm
command appeared in
.At v6 .