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.\"     From: @(#)lo.4	8.1 (Berkeley) 6/5/93
.\" $FreeBSD: src/share/man/man4/disc.4,v 1.2.38.1.6.1 2010/12/21 17:09:25 kensmith Exp $
.\"
.Dd May 25, 2002
.Dt DISC 4
.Os
.Sh NAME
.Nm disc
.Nd software discard network interface
.Sh SYNOPSIS
.Cd "device disc"
.Sh DESCRIPTION
The
.Nm
interface is a software discard mechanism which may be
used for performance analysis and/or software testing.
As with other network interfaces, the discard interface must have
network addresses assigned for each address family with which it is to be used.
These addresses
may be set or changed with the
.Dv SIOCSIFADDR
.Xr ioctl 2 .
.Pp
Each
.Nm
interface is created at runtime using interface cloning.
This is
most easily done with the
.Xr ifconfig 8
.Cm create
command or using the
.Va cloned_interfaces
variable in
.Xr rc.conf 5 .
.Sh SEE ALSO
.Xr inet 4 ,
.Xr intro 4
.\" .Xr ns 4
.Sh HISTORY
The
.Nm
device appears to have been derived from the
.Xr lo 4
device around the time of
.Bx 4.4 .
This manpage was adapted from
.Xr lo 4
and first appeared in
.Fx 5.0 .