t_look()

NAME

t_look - look at the current event on a transport endpoint

SYNOPSIS

#include <xti.h>

int t_look(
	int fd)

DESCRIPTION

Parameters Before call After call
fd x /

This function returns the current event on the transport endpoint specified by fd. This function enables a transport provider to notify a transport user of an asynchronous event when the user is calling functions in synchronous mode. Certain events require immediate notification of the user and are indicated by a specific error, [TLOOK], on the current or next function to be executed.

This function also enables a transport user to poll a transport endpoint periodically for asynchronous events.

VALID STATES

ALL - apart from T_UNINIT

ERRORS

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

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

RETURN VALUE

Upon success, t_look() returns a value that indicates which of the allowable events has occurred, or returns zero if no event exists. One of the following events is returned:

T_LISTEN
Connection indication received.
T_CONNECT
Connect confirmation received.
T_DATA
Normal data received.
T_EXDATA
Expedited data received.
T_DISCONNECT
Disconnection received.
T_UDERR
Datagram error indication.
T_ORDREL
Orderly release indication.
T_GODATA
Flow control restrictions on normal data flow that led to a [TFLOW] error have been lifted. Normal data may be sent again.
T_GOEXDATA
Flow control restrictions on expedited data flow that led to a [TFLOW] error have been lifted. Expedited data may be sent again.

On failure, -1 is returned and t_errno is set to indicate the error.

SEE ALSO

t_open(3)

t_snd(3)

t_sndudata(3)

APPLICATION USAGE

Additional functionality is provided through the Event Management (EM) interface.