tibrvcmTransport_SendRequest()

Function

Declaration

tibrv_status
tibrvcmTransport_SendRequest(
    tibrvcmTransport    cmTransport,
    tibrvMsg            message);
    tibrvMsg*           reply,
    tibrv_f64           timeout);

Purpose

Send a labeled request message and wait for a reply.

Warning 

Blocking can Stall Event Dispatch

This call blocks all other activity on its program thread. If appropriate, programmers must ensure that other threads continue dispatching events on its queues.

Parameter

Description

cmTransport

Send a message using this certified delivery transport.

message

Send this request message.

Wildcard subjects are illegal.

reply

The program supplies a location, and the function stores the inbound reply in that location.

The program need not create the reply message, nor allocate space for it. However, the program must destroy the reply message, even though it did not create it.

timeout

Maximum time (in seconds) that this call can block while waiting for a reply.

TIBRV_WAIT_FOREVER (-1) indicates no timeout (wait without limit for a reply).

Remarks

Programs that receive and process the request message cannot determine that the sender has blocked until a reply arrives.

The sender and receiver must already have a certified delivery agreement, otherwise the request is not certified.

The request message must have a valid destination subject; see tibrvMsg_SetSendSubject().

A certified request does not necessarily imply a certified reply; the replying program determines the type of reply message that it sends.

Operation

This function operates in several synchronous steps:

Procedure 

1. Create a tibrvcmEvent that listens for messages on the reply subject of message.
2. Label and send the outbound message.
3. Block until the listener receives a reply; if the time limit expires before a reply arrives, return the status code TIBRV_TIMEOUT. (The reply event uses a private queue that is not accessible to the program.)
4. Store the reply in the location specified by the reply parameter.
5. Return.

See Also

tibrvcmTransport_Send()

tibrvcmTransport_SendReply()