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. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" From: @(#)lo.4 8.1 (Berkeley) 6/5/93 33.\" $FreeBSD: src/share/man/man4/disc.4,v 1.2.4.1 2003/04/15 18:24:28 trhodes Exp $ 34.\" $DragonFly: src/share/man/man4/disc.4,v 1.2 2003/06/17 04:36:58 dillon Exp $ 35.\" 36.Dd May 25, 2002 37.Dt DISC 4 38.Os 39.Sh NAME 40.Nm disc 41.Nd software discard network interface 42.Sh SYNOPSIS 43.Cd "pseudo-device disc" 44.Sh DESCRIPTION 45The 46.Nm 47interface is a software discard mechanism which may be 48used for performance analysis and/or software testing. 49As with other network interfaces, the discard interface must have 50network addresses assigned for each address family with which it is to be used. 51These addresses 52may be set or changed with the 53.Dv SIOCSIFADDR 54.Xr ioctl 2 . 55.Pp 56Each 57.Nm 58interface is created at runtime using interface cloning. 59This is 60most easily done with the 61.Xr ifconfig 8 62.Cm create 63command or using the 64.Va cloned_interfaces 65variable in 66.Xr rc.conf 5 . 67.Sh SEE ALSO 68.Xr inet 4 , 69.Xr intro 4 70.\" .Xr ns 4 71.Sh HISTORY 72The 73.Nm 74device appears to have been derived from the 75.Xr lo 4 76device around the time of 77.Bx 4.4 . 78This manpage was adapted from 79.Xr lo 4 80and first appeared in 81.Fx 5.0 . 82