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

t_close - close a transport endpoint

#include <xti.h>
int t_close(int fd);

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.

The t_close() function informs the transport provider that the user is finished with the transport endpoint specified by fd, and frees any local library resources associated with the endpoint. In addition, t_close() closes the file associated with the transport endpoint.

The function t_close() should be called from the T_UNBND state. See t_getstate(3NSL). However, this function does not check state information, so it may be called from any state to close a transport endpoint. If this occurs, the local library resources associated with the endpoint will be freed automatically. In addition, close(2) will be issued for that file descriptor; if there are no other descriptors in this process or in another process which references the communication endpoint, any connection that may be associated with that endpoint is broken. The connection may be terminated in an orderly or abortive manner.

A t_close() issued on a connection endpoint may cause data previously sent, or data not yet received, to be lost. It is the responsibility of the transport user to ensure that data is received by the remote peer.

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.


On failure, t_errno is set to the following:


The specified file descriptor does not refer to a transport endpoint.


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).


A system error has occurred during execution of this function.

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.

The XTI interfaces use the header file, xti.h. TLI interfaces should not use this header. They should use the header:

#include <tiuser.h>

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


See attributes(7) for descriptions of the following attributes:

MT Level Safe

close(2), t_getstate(3NSL), t_open(3NSL), t_unbind(3NSL), attributes(7)

May 7, 1998 OmniOS