Tribblix: manual page: t

T_SYNC(3NSL) Networking Services Library Functions T_SYNC(3NSL)

NAME

t_sync - synchronize transport library

SYNOPSIS

#include <xti.h>

int t_sync(int fd);

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.

For the transport endpoint specified by fd, t_sync() synchronizes the
data structures managed by the transport library with information
from the underlying transport provider. In doing so, it can convert
an uninitialized file descriptor (obtained by means of a open(2),
dup(2) or as a result of a fork(2) and exec(2)) to an initialized
transport endpoint, assuming that the file descriptor referenced a
transport endpoint, by updating and allocating the necessary library
data structures. This function also allows two cooperating processes
to synchronize their interaction with a transport provider.

For example, if a process forks a new process and issues an exec(2),
the new process must issue a t_sync() to build the private library
data structure associated with a transport endpoint and to
synchronize the data structure with the relevant provider
information.

It is important to remember that the transport provider treats all
users of a transport endpoint as a single user. If multiple processes
are using the same endpoint, they should coordinate their activities
so as not to violate the state of the transport endpoint. The
function t_sync() returns the current state of the transport endpoint
to the user, thereby enabling the user to verify the state before
taking further action. This coordination is only valid among
cooperating processes; it is possible that a process or an incoming
event could change the endpoint's state after a t_sync() is issued.

If the transport endpoint is undergoing a state transition when
t_sync() is called, the function will fail.

RETURN VALUES

On successful completion, the state of the transport endpoint is
returned. Otherwise, a value of -1 is returned and t_errno is set
to indicate an error. The state returned is one of the following:

T_UNBND
Unbound.

T_IDLE
Idle.

T_OUTCON
Outgoing connection pending.

T_INCON
Incoming connection pending.

T_DATAXFER
Data transfer.

T_OUTREL
Outgoing orderly release (waiting for an orderly
release indication).

T_INREL
Incoming orderly release (waiting for an orderly
release request).

ERRORS

On failure, t_errno is set to one of the following:

TBADF
The specified file descriptor does not refer to a
transport endpoint. This error may be returned when the
fd has been previously closed or an erroneous number
may have been passed to the call.

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).

TSTATECHNG
The transport endpoint is undergoing a state change.

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 value that can be set by the XTI interface and cannot be
set by the TLI interface is:
TPROTO

ATTRIBUTES