ln.4

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)ln.4	3.1	11/24/87
.TH ln 4 
.SH Name
ln \- Lance Ethernet interface
.SH Syntax
.nf
\fBdevice ln0 at ibus? vector lnintr\fR
.\"\fBdevice ln0 at vba0 csr 0x200e0000 vector lnintr\fR
.\".fi
.\".PP
.\"The second line is used for busless small VAX processors.  Other
.\"processors would use the first line. 
.SH Description
.NXR "ln interface" "Lance Ethernet interface"
.NXR "Lance Ethernet interface"
.NXR "Ethernet interface" "Lance Ethernet interface"
The
.PN ln 
interface provides access to a 10 Mb/s Ethernet network through
the Lance controller.
.PP
The host's Internet address is specified at boot time with
an SIOCSIFADDR ioctl.
The
.PN ln 
interface employs the address resolution protocol described in
.MS arp 4p
to map dynamically between Internet and Ethernet addresses on the local
network.
.PP
The interface normally tries to use a trailer encapsulation
to minimize copying data on input and output.  This can be
disabled for an interface by setting the IFF_NOTRAILERS
flag with an SIOCSIFFLAGS ioctl.
Trailers are only used for packets destined for Internet hosts.
.PP
The SIOCSPHYSADDR ioctl can be used to change 
the physical address of the Lance.  The
SIOCRPHYSADDR ioctl can
be used to read the physical address of the Lance.
.PP
The SIOCADDMULTI and SIOCDELMULTI ioctls can be used to add or delete
multicast addresses.  
The Lance recognizes a maximum of 12 multicast addresses.
.PP
The SIOCRDCTRS and SIOCRDZCTRS ioctls can be used to read or 
``read and clear'' the Ethernet driver counters.
The argument to these two ioctls is a pointer to a counter
structure, 
.PN ctrreq, 
found in 
.PN <net/if.h> .
.PP
The SIOCENABLBACK and SIOCDISABLBACK ioctls can be used to enable
and disable the interface loopback mode respectively.
.SH Diagnostics
The diagnostic error messages contain relevant information provided
by the Lance.
.PP
.B "ln%d: can't handle af%d"
.br
The interface was handed
a message with addresses formated in an unsuitable address
family, and the packet was dropped.
.PP
.B "ln%d: memory error (MERR)"
.br
A memory parity error has occurred.
.PP
.B "ln%d: lnalloc: cannot alloc memory ... "
.br
The 
.PN ln
driver was unable to allocate memory for internal data structures.
.PP
.B "ln%d: initialization error"
.br
The
.PN ln
driver was unable to initialize the network interface.
.PP
.B "ln%d: SIOCADDMULTI fail, multicast list full"
.br
Too many multicast requests have been made. 
.SH See Also
arp(4p), inet(4f), intro(4n)