CLTP(4)                   OpenBSD Programmer's Manual                  CLTP(4)

NAME
     cltp - ISO Connectionless Transport Protocol

SYNOPSIS
     #include <sys/socket.h>
     #include <netiso/iso.h>

     int
     socket(AF_ISO, SOCK_DGRAM, 0);

DESCRIPTION
     CLTP is a simple, unreliable datagram protocol which is accessed via the
     SOCK_DGRAM abstraction for the ISO protocol family.  CLTP sockets are
     connectionless, and are normally used with the sendto and recvfrom calls,
     though the connect(2) call may also be used to fix the destination for
     future packets (in which case the recv(2) or read(2) and send(2) or
     write(2) system calls may be used).

     CLTP address formats are identical to those used by TP.  In particular
     CLTP provides a service selector in addition to the normal ISO NSAP. Note
     that the CLTP selector space is separate from the TP selector space (i.e.
     a CLTP selector may not be ``connected'' to a TP selector).

     Options at the CLNP network level may be used with CLTP; see clnp(4).

DIAGNOSTICS
     A socket operation may fail with one of the following errors returned:

     [EISCONN]        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 al-
                      ready connected;

     [ENOTCONN]       when trying to send a datagram, but no destination ad-
                      dress is specified, and the socket hasn't been connect-
                      ed;

     [ENOBUFS]        when the system runs out of memory for an internal data
                      structure;

     [EADDRINUSE]     when an attempt is made to create a socket with a selec-
                      tor which has already been allocated;

     [EADDRNOTAVAIL]  when an attempt is made to create a socket with a net-
                      work address for which no network interface exists.

SEE ALSO
     getsockopt(2), recv(2), send(2), socket(2), clnp(4), iso(4), netintro(4)

OpenBSD 3.0                      June 9, 1993                                1
