New sentence, new line.

This commit is contained in:
wiz 2004-12-05 13:28:54 +00:00
parent d61c6aa90c
commit 65662157da

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@ -1,4 +1,4 @@
.\" $NetBSD: tun.4,v 1.16 2004/12/05 13:26:39 peter Exp $ .\" $NetBSD: tun.4,v 1.17 2004/12/05 13:28:54 wiz Exp $
.\" .\"
.\" Copyright (c) 1996-2003 The NetBSD Foundation, Inc. .\" Copyright (c) 1996-2003 The NetBSD Foundation, Inc.
.\" All rights reserved. .\" All rights reserved.
@ -72,13 +72,14 @@ interface.
.Pp .Pp
To use a To use a
.Nm tun .Nm tun
device, the administrator must first create the interface. This can device, the administrator must first create the interface.
be done by using the This can be done by using the
.Xr ifconfig 8 .Xr ifconfig 8
.Cm create .Cm create
command, or via the command, or via the
.Dv SIOCIFCREATE .Dv SIOCIFCREATE
ioctl. An ioctl.
An
.Fn open .Fn open
call on call on
.Pa /dev/tun Ns Sy N , .Pa /dev/tun Ns Sy N ,
@ -97,10 +98,12 @@ and
.Dv SIOCSIFNETMASK , .Dv SIOCSIFNETMASK ,
and thus can be used with and thus can be used with
.Xr ifconfig 8 .Xr ifconfig 8
like any other interface. At boot time, they are like any other interface.
At boot time, they are
.Dv POINTOPOINT .Dv POINTOPOINT
interfaces, but this can be changed; see the description of the control interfaces, but this can be changed; see the description of the control
device, below. When the system chooses to transmit a packet on the device, below.
When the system chooses to transmit a packet on the
network interface, the packet can be read from the control device network interface, the packet can be read from the control device
.Po .Po
it appears there as it appears there as
@ -118,9 +121,8 @@ is exclusive-open
it cannot be opened if it is already open it cannot be opened if it is already open
.Pc .Pc
and is restricted to the super-user and is restricted to the super-user
.Po .Pq regardless of file system permissions .
regardless of file system permissions A
.Pc . A
.Fn read .Fn read
call will return an error call will return an error
.Pq Er EHOSTDOWN .Pq Er EHOSTDOWN
@ -133,7 +135,8 @@ Once the interface is ready,
will return a packet if one is available; if not, it will either block will return a packet if one is available; if not, it will either block
until one is or return until one is or return
.Er EAGAIN , .Er EAGAIN ,
depending on whether non-blocking I/O has been enabled. If the packet depending on whether non-blocking I/O has been enabled.
If the packet
is longer than is allowed for in the buffer passed to is longer than is allowed for in the buffer passed to
.Fn read , .Fn read ,
the extra data will be silently dropped. the extra data will be silently dropped.
@ -143,14 +146,16 @@ to the network interface output routine
.Pq Sq Li tunoutput . .Pq Sq Li tunoutput .
The destination address is in The destination address is in
.Sq Li struct sockaddr .Sq Li struct sockaddr
format. The actual length of the prepended address is in the member format.
The actual length of the prepended address is in the member
.Sq Li sa_len . .Sq Li sa_len .
The packet data follows immediately. The packet data follows immediately.
A A
.Xr write 2 .Xr write 2
call passes a packet in to be call passes a packet in to be
.Dq received .Dq received
on the pseudo-interface. Each on the pseudo-interface.
Each
.Fn write .Fn write
call supplies exactly one packet; the packet length is taken from the call supplies exactly one packet; the packet length is taken from the
amount of data provided to amount of data provided to
@ -178,9 +183,9 @@ calls are supported
.It Dv TUNSDEBUG .It Dv TUNSDEBUG
The argument should be a pointer to an The argument should be a pointer to an
.Va int ; .Va int ;
this sets the internal debugging variable to that value. What, if this sets the internal debugging variable to that value.
anything, this variable controls is not documented here; see the source What, if anything, this variable controls is not documented here;
code. see the source code.
.It Dv TUNGDEBUG .It Dv TUNGDEBUG
The argument should be a pointer to an The argument should be a pointer to an
.Va int ; .Va int ;
@ -194,12 +199,14 @@ or
.Dv IFF_BROADCAST .Dv IFF_BROADCAST
(optionally (optionally
.Dv IFF_MULTICAST .Dv IFF_MULTICAST
may be or'ed into the value). The type of the corresponding may be or'ed into the value).
The type of the corresponding
.Em tun Ns Sy n .Em tun Ns Sy n
interface is set to the supplied type. If the value is anything else, interface is set to the supplied type.
an If the value is anything else, an
.Er EINVAL .Er EINVAL
error occurs. The interface must be down at the time; if it is up, an error occurs.
The interface must be down at the time; if it is up, an
.Er EBUSY .Er EBUSY
error occurs. error occurs.
.It Dv TUNSLMODE .It Dv TUNSLMODE