xref: /freebsd/usr.bin/nice/nice.1 (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
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28.\"	@(#)nice.1	8.1 (Berkeley) 6/6/93
29.\" $FreeBSD$
30.\"
31.Dd February 24, 2011
32.Dt NICE 1
33.Os
34.Sh NAME
35.Nm nice
36.Nd execute a utility at an altered scheduling priority
37.Sh SYNOPSIS
38.Nm
39.Op Fl n Ar increment
40.Ar utility
41.Op Ar argument ...
42.Sh DESCRIPTION
43The
44.Nm
45utility runs
46.Ar utility
47at an altered scheduling priority, by incrementing its
48.Dq nice
49value by the specified
50.Ar increment ,
51or a default value of 10.
52The lower the nice value of a process, the higher its scheduling priority.
53.Pp
54The superuser may specify a negative increment in order to run a utility
55with a higher scheduling priority.
56.Pp
57Some shells may provide a builtin
58.Nm
59command which is similar or identical to this utility.
60Consult the
61.Xr builtin 1
62manual page.
63.Sh ENVIRONMENT
64The
65.Ev PATH
66environment variable is used to locate the requested
67.Ar utility
68if the name contains no
69.Ql /
70characters.
71.Sh EXIT STATUS
72If
73.Ar utility
74is invoked, the exit status of
75.Nm
76is the exit status of
77.Ar utility .
78.Pp
79An exit status of 126 indicates
80.Ar utility
81was found, but could not be executed.
82An exit status of 127 indicates
83.Ar utility
84could not be found.
85.Sh EXAMPLES
86Execute utility
87.Sq date
88at priority 5 assuming the priority of the
89shell is 0:
90.Pp
91.Dl "nice -n 5 date"
92.Pp
93Execute utility
94.Sq date
95at priority -19 assuming the priority of the
96shell is 0 and you are the super-user:
97.Pp
98.Dl "nice -n 16 nice -n -35 date"
99.Sh COMPATIBILITY
100The traditional
101.Fl Ns Ar increment
102option has been deprecated but is still supported.
103.Sh SEE ALSO
104.Xr builtin 1 ,
105.Xr csh 1 ,
106.Xr idprio 1 ,
107.Xr rtprio 1 ,
108.Xr getpriority 2 ,
109.Xr setpriority 2 ,
110.Xr renice 8
111.Sh STANDARDS
112The
113.Nm
114utility conforms to
115.St -p1003.1-2001 .
116.Sh HISTORY
117A
118.Nm
119utility appeared in
120.At v4 .
121