1.\" Copyright (c) 1983, 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" From: @(#)lo.4 8.1 (Berkeley) 6/5/93 29.\" $FreeBSD: src/share/man/man4/disc.4,v 1.2.4.1 2003/04/15 18:24:28 trhodes Exp $ 30.\" $DragonFly: src/share/man/man4/disc.4,v 1.2 2003/06/17 04:36:58 dillon Exp $ 31.\" 32.Dd May 25, 2002 33.Dt DISC 4 34.Os 35.Sh NAME 36.Nm disc 37.Nd software discard network interface 38.Sh SYNOPSIS 39.Cd "pseudo-device disc" 40.Sh DESCRIPTION 41The 42.Nm 43interface is a software discard mechanism which may be 44used for performance analysis and/or software testing. 45As with other network interfaces, the discard interface must have 46network addresses assigned for each address family with which it is to be used. 47These addresses 48may be set or changed with the 49.Dv SIOCSIFADDR 50.Xr ioctl 2 . 51.Pp 52Each 53.Nm 54interface is created at runtime using interface cloning. 55This is 56most easily done with the 57.Xr ifconfig 8 58.Cm create 59command or using the 60.Va cloned_interfaces 61variable in 62.Xr rc.conf 5 . 63.Sh SEE ALSO 64.Xr inet 4 , 65.Xr intro 4 66.\" .Xr ns 4 67.Sh HISTORY 68The 69.Nm 70device appears to have been derived from the 71.Xr lo 4 72device around the time of 73.Bx 4.4 . 74This manpage was adapted from 75.Xr lo 4 76and first appeared in 77.Fx 5.0 . 78