.\" Copyright (c) 1983, 1991 The Regents of the University of California.
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.\" This product includes software developed by the University of
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.\" @(#)imp.4 6.5 (Berkeley) 3/28/91
.Fd #include <sys/socket.h>
.Fd #include <netinet/in.h>
.Fd #include <netimp/if_imp.h>
.Fn socket AF_IMPLINK SOCK_RAW proto
The raw imp socket provides direct access to the
network interface. Users send packets through
calls, and receive packets with the
calls. All outgoing packets must have an 1822 96-bit
leader on the front. Likewise, packets received
by the user will have this leader on the front. The
1822 leader and the legal values for the various fields
are defined in the include file
The raw imp interface automatically installs the length
and destination address in the 1822 leader of all
outgoing packets; these need not be filled in by the user.
If the protocol selected,
messages except RFNM and incompletes
which are not input data for a kernel protocol.
only messages for the specified link type will be received.
An operation on a socket may fail with one of the following
.Bl -tag -width [EADDRNOTAVAIL]
when trying to establish a connection on a socket which
already has one, or when trying to send a datagram with the destination
address specified and the socket is already connected;
when trying to send a datagram, but
no destination address is specified, and the socket hasn't been
when the system runs out of memory for
an internal data structure;
eight messages to the destination host are outstanding,
and another eight are already queued for output;
when an attempt is made to create a
socket with a network address for which no network interface