NAME
cltp
-
ISO
Connectionless Transport Protocol
SYNOPSIS
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(2)
and
recvfrom(2)
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 already connected;
- [
ENOTCONN
] -
when trying to send a datagram, but
no destination address is specified, and the socket hasn't been
connected;
- [
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 selector which has already been
allocated;
- [
EADDRNOTAVAIL
] -
when an attempt is made to create a
socket with a network address for which no network interface
exists.
SEE ALSO
getsockopt(2),
recv(2),
send(2),
socket(2),
clnp(4),
intro(4),
iso(4)