xref: /freebsd/usr.bin/nice/nice.1 (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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28.\"	@(#)nice.1	8.1 (Berkeley) 6/6/93
29.\"
30.Dd February 24, 2011
31.Dt NICE 1
32.Os
33.Sh NAME
34.Nm nice
35.Nd execute a utility at an altered scheduling priority
36.Sh SYNOPSIS
37.Nm
38.Op Fl n Ar increment
39.Ar utility
40.Op Ar argument ...
41.Sh DESCRIPTION
42The
43.Nm
44utility runs
45.Ar utility
46at an altered scheduling priority, by incrementing its
47.Dq nice
48value by the specified
49.Ar increment ,
50or a default value of 10.
51The lower the nice value of a process, the higher its scheduling priority.
52.Pp
53The superuser may specify a negative increment in order to run a utility
54with a higher scheduling priority.
55.Pp
56Some shells may provide a builtin
57.Nm
58command which is similar or identical to this utility.
59Consult the
60.Xr builtin 1
61manual page.
62.Sh ENVIRONMENT
63The
64.Ev PATH
65environment variable is used to locate the requested
66.Ar utility
67if the name contains no
68.Ql /
69characters.
70.Sh EXIT STATUS
71If
72.Ar utility
73is invoked, the exit status of
74.Nm
75is the exit status of
76.Ar utility .
77.Pp
78An exit status of 126 indicates
79.Ar utility
80was found, but could not be executed.
81An exit status of 127 indicates
82.Ar utility
83could not be found.
84.Sh EXAMPLES
85Execute utility
86.Sq date
87at priority 5 assuming the priority of the
88shell is 0:
89.Pp
90.Dl "nice -n 5 date"
91.Pp
92Execute utility
93.Sq date
94at priority -19 assuming the priority of the
95shell is 0 and you are the super-user:
96.Pp
97.Dl "nice -n 16 nice -n -35 date"
98.Sh COMPATIBILITY
99The traditional
100.Fl Ns Ar increment
101option has been deprecated but is still supported.
102.Sh SEE ALSO
103.Xr builtin 1 ,
104.Xr csh 1 ,
105.Xr idprio 1 ,
106.Xr rtprio 1 ,
107.Xr getpriority 2 ,
108.Xr setpriority 2 ,
109.Xr renice 8
110.Sh STANDARDS
111The
112.Nm
113utility conforms to
114.St -p1003.1-2001 .
115.Sh HISTORY
116A
117.Nm
118utility appeared in
119.At v4 .
120