.\"	$OpenBSD: random.4,v 1.1 1996/12/17 22:56:03 millert Exp $
.\"
.\" Copyright (c) 1996 Michael Shalayeff
.\"
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.\" modification, are permitted provided that the following conditions
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.\"    must display the following acknowledgement:
.\"	This product includes software developed by Michael Shalayeff.
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.\"    may be used to endorse or promote products derived from this software
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.Dd March 25, 1996
.Dt RND 4
.Os OpenBSD
.Sh NAME
.Nm random
.Nm srandom
.Nm urandom
.Nm prandom
.Nd random data source devices.
.Sh SYNOPSIS
.Cd "pseudo-device random"
.Sh DESCRIPTION
The
.Nm
device produces random data, with different random quality.
{s,u}random devices generates random data based on the system activity
(like disk and network devices).
.Pp
.Bl -hang -width Ds
.It random
reserved for nuclear noise generators.
.It srandom
strong random data.
.It urandom
same as above, but does not guaranties the data to be strong.
.It prandom
simple pseudo-random generator (as it is in the kernel).
.Sh SEE ALSO
random(9)
.Sh FILES
.Bl -tag -width /dev/random, /dev/srandom, /dev/urandom, /dev/prandom
.It Pa /dev/random, /dev/srandom, /dev/urandom, /dev/prandom
.El
.Sh HISTORY
An
.Nm
device appeared in Linux operating system.