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.\"	@(#)nice.1	8.1 (Berkeley) 6/6/93
.\"	$Id$
.\"
.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 nice
.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 
assumed 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 nice .
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 nice .
.Sh EXAMPLES
.Pp
$ 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 getpriority 2 ,
.Xr setpriority 2 ,
.Xr csh 1 ,
.Xr renice 8
.Sh HISTORY
A
.Nm nice
command appeared in
.At v6 .
.Sh BUGS
.Nm Nice
is particular to
.Xr sh  1  .
If you use
.Xr csh  1  ,
then commands executed with ``&'' are automatically immune to hangup
signals while in the background.
.Pp
.Nm Nice
is built into
.Xr csh  1
with a slightly different syntax than described here.  The form
.Ql nice +10
nices to positive nice, and
.Ql nice \-10
can be used
by the super-user to give a process more of the processor.