xref: /freebsd/usr.bin/nice/nice.1 (revision 7c43148a974877188a930e4078a164f83da8e652)
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28.Dd February 24, 2011
29.Dt NICE 1
30.Os
31.Sh NAME
32.Nm nice
33.Nd execute a utility at an altered scheduling priority
34.Sh SYNOPSIS
35.Nm
36.Op Fl n Ar increment
37.Ar utility
38.Op Ar argument ...
39.Sh DESCRIPTION
40The
41.Nm
42utility runs
43.Ar utility
44at an altered scheduling priority, by incrementing its
45.Dq nice
46value by the specified
47.Ar increment ,
48or a default value of 10.
49The lower the nice value of a process, the higher its scheduling priority.
50.Pp
51The superuser may specify a negative increment in order to run a utility
52with a higher scheduling priority.
53.Pp
54Some shells may provide a builtin
55.Nm
56command which is similar or identical to this utility.
57Consult the
58.Xr builtin 1
59manual page.
60.Sh ENVIRONMENT
61The
62.Ev PATH
63environment variable is used to locate the requested
64.Ar utility
65if the name contains no
66.Ql /
67characters.
68.Sh EXIT STATUS
69If
70.Ar utility
71is invoked, the exit status of
72.Nm
73is the exit status of
74.Ar utility .
75.Pp
76An exit status of 126 indicates
77.Ar utility
78was found, but could not be executed.
79An exit status of 127 indicates
80.Ar utility
81could not be found.
82.Sh EXAMPLES
83Execute utility
84.Sq date
85at priority 5 assuming the priority of the
86shell is 0:
87.Pp
88.Dl "nice -n 5 date"
89.Pp
90Execute utility
91.Sq date
92at priority -19 assuming the priority of the
93shell is 0 and you are the super-user:
94.Pp
95.Dl "nice -n 16 nice -n -35 date"
96.Sh COMPATIBILITY
97The traditional
98.Fl Ns Ar increment
99option has been deprecated but is still supported.
100.Sh SEE ALSO
101.Xr builtin 1 ,
102.Xr csh 1 ,
103.Xr idprio 1 ,
104.Xr rtprio 1 ,
105.Xr getpriority 2 ,
106.Xr setpriority 2 ,
107.Xr renice 8
108.Sh STANDARDS
109The
110.Nm
111utility conforms to
112.St -p1003.1-2001 .
113.Sh HISTORY
114A
115.Nm
116utility appeared in
117.At v4 .
118