1.\"
2.\" Copyright (c) 1995
3.\"	Mark Murray.  All rights reserved.
4.\"
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6.\" modification, are permitted provided that the following conditions
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10.\" 2. Redistributions in binary form must reproduce the above copyright
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14.\" THIS SOFTWARE IS PROVIDED BY MARK MURRAY AND CONTRIBUTORS ``AS IS'' AND
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16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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26.\" $FreeBSD: src/usr.sbin/rndcontrol/rndcontrol.8,v 1.13.2.2 2001/12/21 09:05:32 ru Exp $
27.\" $DragonFly: src/usr.sbin/rndcontrol/rndcontrol.8,v 1.4 2006/03/26 22:56:58 swildner Exp $
28.\"
29.Dd October 20, 1995
30.Dt RNDCONTROL 8
31.Os
32.Sh NAME
33.Nm rndcontrol
34.Nd a utility for manipulating the
35.Pa /dev/random
36device
37.Sh SYNOPSIS
38.Nm
39.Op Fl q
40.Op Fl s Ar irq_no
41.Op Fl c Ar irq_no
42.Sh DESCRIPTION
43The
44.Nm
45command is used to set which interrupts are used to help randomise
46the
47.Dq "pool of entropy"
48maintained by the kernel.
49The
50.Pa /dev/random
51and
52.Pa /dev/urandom
53devices are the user interface to this source of randomness.
54Any changes take effect immediately.
55.Pp
56The following command line options are supported:
57.Bl -tag -width indent
58.It Fl q
59Turn off all output except errors.
60.It Fl s Ar n
61Allow IRQ
62.Ar n
63to be used as a source of randomness.
64This option may be repeated for
65more than one IRQ.
66.It Fl c Ar n
67Stop IRQ
68.Ar n
69from being used as a source of randomness.
70This option may be repeated for
71more than one IRQ.
72.El
73.Pp
74The default is to have no IRQ's being used.
75.Sh FILES
76.Bl -tag -width ".Pa /dev/urandom" -compact
77.It Pa /dev/random
78secure random device
79.It Pa /dev/urandom
80random device
81.El
82.Sh SEE ALSO
83.Xr random 4
84.Sh HISTORY
85The
86.Nm
87utility first appeared in
88.Fx 2.1.5 .
89.Sh AUTHORS
90.An -nosplit
91.An Theodore Ts'o
92wrote the core code.
93.An Mark Murray
94ported this code to
95.Fx
96and wrote the support routines and constructed the man pages.
97.Sh BUGS
98Sure to be some.
99