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LANCE(3)                   Library Functions Manual                   LANCE(3)

       lance - LANCE Ethernet device

       bind -a #l /net


       The  LANCE Ethernet interface is a directory containing 9 stream direc-
       tories: one for each of 8 Ethernet packet types and a clone file.

       Each stream directory contains files to control the stream, receive and
       send data, and supply statistics.  Incoming Ethernet packets are demul-
       tiplexed by packet type and passed up the  corresponding  open  stream.
       Reading  from the data file reads packets at the head of the stream.  A
       read will terminate at packet boundaries.  Each write to the data  file
       causes  a  packet to be sent.  The Ethernet address of the interface is
       inserted into the packet header as the source address.

       A stream is assigned a packet type by opening its ctl file and  writing
       connect  n where n is a decimal integer constant identifying the Ether-
       net packet type.  A value of -1 stands  for  all  types.   If  multiple
       streams  are  assigned  to  a given packet type a copy of the packet is
       passed up each stream.

       Reading the type file returns the decimal value of the assigned  Ether-
       net packet type.  Reading the stats file returns status information and
       the Ethernet address of the interface.

       An interface normally receives only packets whose  destination  address
       is   that   of   the   interface   or   is   the   broadcast   address,
       ff:ff:ff:ff:ff:ff.  The interface can be made to receive all packets on
       the  network  by  writing  the string promiscuous to the ctl file.  The
       interface remains promiscuous until the control file  is  closed.   The
       extra packets are passed up only streams of type -1.