T_RCVDIS(3NSL) Networking Services Library Functions T_RCVDIS(3NSL)
NAME
t_rcvdis - retrieve information from disconnection
SYNOPSIS
#include <xti.h>
int t_rcvdis(
int fd,
struct t_discon *discon);
DESCRIPTION
This routine is part of the
XTI interfaces which evolved from the
TLI interfaces.
XTI represents the future evolution of these interfaces.
However,
TLI interfaces are supported for compatibility. When using a
TLI routine that has the same name as an
XTI routine, the
tiuser.h header
file must be used. Refer to the
TLI COMPATIBILITY section for a
description of differences between the two interfaces.
This function is used to identify the cause of a disconnection and to
retrieve any user data sent with the disconnection. The argument
fd identifies the local transport endpoint where the connection existed, and
discon points to a
t_discon structure containing the following members:
struct netbuf udata;
int reason;
int sequence;
The field
reason specifies the reason for the disconnection through a
protocol-dependent reason code,
udata identifies any user data that was
sent with the disconnection, and
sequence may identify an outstanding
connection indication with which the disconnection is associated. The
field
sequence is only meaningful when
t_rcvdis() is issued by a passive
transport user who has executed one or more
t_listen(3NSL) functions and
is processing the resulting connection indications. If a disconnection
indication occurs,
sequence can be used to identify which of the
outstanding connection indications is associated with the disconnection.
The
maxlen field of
udata may be set to zero, if the user does not care
about incoming data. If, in addition, the user does not need to know the
value of
reason or
sequence,
discon may be set to
NULL and any user
data associated with the disconnection indication shall be discarded.
However, if a user has retrieved more than one outstanding connection
indication by means of
t_listen(3NSL), and
discon is a null pointer, the
user will be unable to identify with which connection indication the
disconnection is associated.
RETURN VALUES
Upon successful completion, a value of
0 is returned. Otherwise, a
value of -1 is returned and
t_errno is set to indicate an error.
VALID STATES
T_DATAXFER,
T_OUTCON,
T_OUTREL,
T_INREL,
T_INCON(ocnt > 0).
ERRORS
On failure,
t_errno is set to one of the following:
TBADF The specified file descriptor does not refer to a
transport endpoint.
TBUFOVFLW The number of bytes allocated for incoming data
(maxlen) is greater than
0 but not sufficient to store the data.
If
fd is a passive endpoint with
ocnt > 1, it remains in
state
T_INCON; otherwise, the endpoint state is set to
T_IDLE. TNODIS No disconnection indication currently exists on the
specified transport endpoint.
TNOTSUPPORT This function is not supported by the underlying transport
provider.
TOUTSTATE The communications endpoint referenced by
fd is not in
one of the states in which a call to this function is
valid.
TPROTO This error indicates that a communication problem has been
detected between XTI and the transport provider for which
there is no other suitable XTI error
(t_errno).
TSYSERR A system error has occurred during execution of this
function.
TLI COMPATIBILITY
The
XTI and
TLI interface definitions have common names but use different
header files. This, and other semantic differences between the two
interfaces are described in the subsections below.
Interface Header
The
XTI interfaces use the header file,
xti.h.
TLI interfaces should
not use this header. They should use the header:
#include <tiuser.h>
Error Description Values
The
t_errno values
TPROTO and
TOUTSTATE can be set by the
XTI interface
but not by the
TLI interface.
A failure return, and a
t_errno value that this routine can set under
different circumstances than its
XTI counterpart is
TBUFOVFLW. It can be
returned even when the
maxlen field of the corresponding buffer has been
set to zero.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+---------------+-----------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+-----------------+
|MT Level | Safe |
+---------------+-----------------+
SEE ALSO
t_alloc(3NSL),
t_connect(3NSL),
t_listen(3NSL),
t_open(3NSL),
t_snddis(3NSL),
attributes(7) May 7, 1998
T_RCVDIS(3NSL)