xref: /freebsd/usr.bin/nice/nice.1 (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
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32.\"	@(#)nice.1	8.1 (Berkeley) 6/6/93
33.\" $FreeBSD$
34.\"
35.Dd June 6, 1993
36.Dt NICE 1
37.Os BSD 4
38.Sh NAME
39.Nm nice
40.Nd execute a command at a low scheduling priority
41.Sh SYNOPSIS
42.Nm
43.Op Fl Ns Ar number
44.Ar command
45.Op Ar arguments
46.Sh DESCRIPTION
47.Nm Nice
48runs
49.Ar command
50at a low priority.
51(Think of low and slow).
52If
53.Fl Ns Ar number
54is not given,
55.Nm
56assumes the value 10.
57The priority is a value in the range -20 to 20.
58The default priority is 0, priority 20 is the lowest possible.
59.Nm Nice
60will execute
61.Ar command
62at priority
63.Ar number
64relative to the priority
65of
66.Nm .
67Higher priorities than the
68current process priority can only requested by the
69super-user.
70Negative numbers are expressed as
71.Fl - Ns Ar number .
72.Pp
73The returned exit status is the exit value from the
74command executed by
75.Nm .
76.Pp
77Some shells may provide a builtin
78.Nm
79command which is similar or identical to this utility.
80Consult the
81.Xr builtin 1
82manual page.
83.Sh EXAMPLES
84.Pp
85$ nice -5 date
86.Pp
87Execute command
88.Sq date
89at priority 5 assuming the priority of the
90shell is 0.
91.Pp
92# nice -16 nice --35 date
93.Pp
94Execute command
95.Sq date
96at priority -19 assuming the priority of the
97shell is 0 and you are the super-user.
98.Sh SEE ALSO
99.Xr builtin 1 ,
100.Xr csh 1 ,
101.Xr idprio 1 ,
102.Xr rtprio 1 ,
103.Xr getpriority 2 ,
104.Xr setpriority 2 ,
105.Xr renice 8
106.Sh HISTORY
107A
108.Nm
109command appeared in
110.At v6 .
111