1.\" $NetBSD: sl.4,v 1.1 1996/08/10 21:26:14 explorer Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" From: @(#)lo.4 8.1 (Berkeley) 6/5/93 35.\" $FreeBSD: src/share/man/man4/sl.4,v 1.8.2.1 2000/12/08 14:59:08 ru Exp $ 36.\" $DragonFly: src/share/man/man4/sl.4,v 1.2 2003/06/17 04:36:59 dillon Exp $ 37.\" 38.Dd August 10, 1996 39.Dt SL 4 40.Os 41.Sh NAME 42.Nm sl 43.Nd slip network interface 44.Sh SYNOPSIS 45.Cd "pseudo-device sl" Op Ar count 46.Sh DESCRIPTION 47The 48.Nm 49interface allows serial lines to be used as network interfaces using the 50.Em slip 51protocol. The 52.Nm 53interface can use Van Jacobson TCP header compression and ICMP filtering. 54This is arranged by using the various link-level flags to the 55.Xr ifconfig 8 56command: 57.Pp 58.Bl -tag -width LINK0X -compact 59.It Em link0 60Enable VJ header compression. 61.It Em link1 62Suppress ICMP traffic. 63.It Em link2 64Enable VJ header compression autodetection. This will turn on the 65.Em link0 66flag as soon as the first VJ-compressed packet has been seen by 67the driver. 68.El 69.Sh DIAGNOSTICS 70.Bl -diag 71.It sl%d: af%d not supported. 72The interface was handed 73a message with addresses formatted in an unsuitable address 74family; the packet was dropped. 75.El 76.Sh SEE ALSO 77.Xr inet 4 , 78.Xr intro 4 , 79.Xr slattach 8 , 80.Xr sliplogin 8 , 81.Xr slstat 8 82