1.\"
2.\" Copyright (c) 1995
3.\"	Mark Murray.  All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
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 1.2 2003/06/17 04:30:02 dillon 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.Pp
76.Sh FILES
77.Bl -tag -width ".Pa /dev/urandom" -compact
78.It Pa /dev/random
79secure random device
80.It Pa /dev/urandom
81random device
82.El
83.Sh BUGS
84Sure to be some.
85.Sh SEE ALSO
86.Xr random 4
87.Sh AUTHORS
88.An -nosplit
89.An Theodore Ts'o
90wrote the core code.
91.An Mark Murray
92ported this code to
93.Fx
94and wrote the support routines and constructed the man pages.
95.Sh HISTORY
96The
97.Nm
98utility first appeared in
99.Fx 2.1.5 .
100