Look at the current event on a transport endpoint.
X/Open Transport Interface Library (libxti.a)
#include <xti.h>int t_look (fd)
int fd;The t_look subroutine returns the current event on the transport endpoint specified by the fd parameter. This subroutine enables a transport provider to notify a transport user of an asynchronous event when the user is calling subroutines in synchronous mode. Certain events require immediate notification of the user and are indicated by a specific error, TLOOK, on the current or next subroutine to be executed. Details on events which cause subroutines to fail, T_LOOK, may be found in Section 4.6, Events and TLOOK Error Indication.
This subroutine also enables a transport user to poll a transport endpoint periodically for asynchronous events.
Additional functionality is provided through the Event Management (EM) interface.
| Item | Description |
|---|---|
| fd | Specifies the transport endpoint. |
ALL - apart from T_UNINIT.
Upon success, the t_look subroutine 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:
| Event | Description |
|---|---|
| T_LISTEN | Connection indication received. |
| T_CONNECT | Connect confirmation received. |
| T_DATA | Normal data received. |
| T_EXDATA | Expedited data received. |
| T_DISCONNECT | Disconnect 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.
On failure, t_errno is set to one of the following:
| Value | Description |
|---|---|
| TBADF | The specified file descriptor does not refer to a transport endpoint. |
| TSYSERR | A system error has occurred during execution of this subroutine. |
| TPROTO | This error indicates that a communication problem has been detected between the X/Open Transport Interface and the transport provider for which there is no other suitable X/Open Transport Interface (t_errno). |