freebsd-nq/usr.bin/nice/nice.1
2002-12-27 12:15:40 +00:00

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.\" @(#)nice.1 8.1 (Berkeley) 6/6/93
.\" $FreeBSD$
.\"
.Dd June 6, 1993
.Dt NICE 1
.Os
.Sh NAME
.Nm nice
.Nd execute a utility at an altered scheduling priority
.Sh SYNOPSIS
.Nm
.Op Fl n Ar increment
.Ar utility
.Op Ar argument ...
.Sh DESCRIPTION
The
.Nm
utility runs
.Ar utility
at an altered scheduling priority, by incrementing its
.Dq nice
value by the specified
.Ar increment ,
or a default value of 10.
The lower the nice value of a process, the higher its scheduling priority.
.Pp
The superuser may specify a negative increment in order to run a utility
with a higher scheduling priority.
.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 ENVIRONMENT
The
.Ev PATH
environment variable is used to locate the requested
.Ar utility
if the name contains no
.Ql /
characters.
.Sh EXAMPLES
Execute utility
.Sq date
at priority 5 assuming the priority of the
shell is 0:
.Pp
.Dl "nice -n 5 date"
.Pp
Execute utility
.Sq date
at priority -19 assuming the priority of the
shell is 0 and you are the super-user:
.Pp
.Dl "nice -n 16 nice -n -35 date"
.Sh DIAGNOSTICS
If
.Ar utility
is invoked, the exit status of
.Nm
is the exit status of
.Ar utility .
.Pp
An exit status of 126 indicates
.Ar utility
was found, but could not be executed.
An exit status of 127 indicates
.Ar utility
could not be found.
.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 COMPATIBILITY
The traditional
.Fl Ns Ar increment
option has been deprecated but is still supported.
.Sh STANDARDS
The
.Nm
utility conforms to
.St -p1003.1-2001 .
.Sh HISTORY
A
.Nm
utility appeared in
.At v4 .