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 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY MARK MURRAY AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 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