xref: /freebsd/usr.bin/nice/nice.1 (revision ea906c4152774dff300bb26fbfc1e4188351c89a)
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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
38.Sh NAME
39.Nm nice
40.Nd execute a utility at an altered scheduling priority
41.Sh SYNOPSIS
42.Nm
43.Op Fl n Ar increment
44.Ar utility
45.Op Ar argument ...
46.Sh DESCRIPTION
47The
48.Nm
49utility runs
50.Ar utility
51at an altered scheduling priority, by incrementing its
52.Dq nice
53value by the specified
54.Ar increment ,
55or a default value of 10.
56The lower the nice value of a process, the higher its scheduling priority.
57.Pp
58The superuser may specify a negative increment in order to run a utility
59with a higher scheduling priority.
60.Pp
61Some shells may provide a builtin
62.Nm
63command which is similar or identical to this utility.
64Consult the
65.Xr builtin 1
66manual page.
67.Sh ENVIRONMENT
68The
69.Ev PATH
70environment variable is used to locate the requested
71.Ar utility
72if the name contains no
73.Ql /
74characters.
75.Sh EXIT STATUS
76If
77.Ar utility
78is invoked, the exit status of
79.Nm
80is the exit status of
81.Ar utility .
82.Pp
83An exit status of 126 indicates
84.Ar utility
85was found, but could not be executed.
86An exit status of 127 indicates
87.Ar utility
88could not be found.
89.Sh EXAMPLES
90Execute utility
91.Sq date
92at priority 5 assuming the priority of the
93shell is 0:
94.Pp
95.Dl "nice -n 5 date"
96.Pp
97Execute utility
98.Sq date
99at priority -19 assuming the priority of the
100shell is 0 and you are the super-user:
101.Pp
102.Dl "nice -n 16 nice -n -35 date"
103.Sh COMPATIBILITY
104The traditional
105.Fl Ns Ar increment
106option has been deprecated but is still supported.
107.Sh SEE ALSO
108.Xr builtin 1 ,
109.Xr csh 1 ,
110.Xr idprio 1 ,
111.Xr rtprio 1 ,
112.Xr getpriority 2 ,
113.Xr setpriority 2 ,
114.Xr renice 8
115.Sh STANDARDS
116The
117.Nm
118utility conforms to
119.St -p1003.1-2001 .
120.Sh HISTORY
121A
122.Nm
123utility appeared in
124.At v4 .
125