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Chapter 3 - Endpoints / Endpoints Reference

Functions / Functions for Connection-Oriented Transaction-Based Endpoints

OTCancelReply

Cancels an outstanding call to the OTRcvRequest function.

C INTERFACE

OSStatus OTCancelReply(EndpointRef ref, OTSequence seq);

C++ INTERFACE

OSStatus TEndpoint::CancelReply(OTSequence seq);

PARAMETERS

ref

The endpoint reference of the endpoint that has sent the request being canceled.

seq

A long, specifying the transaction ID of the request being canceled. You must specify the same value that was passed to you in the seq field of the req parameter to the OTRcvRequest function. If you specify 0 for this parameter, the provider cancels all outstanding incoming requests. If you specify an invalid sequence number, the provider does not do anything.

DESCRIPTION

When you make a call to the OTRcvRequest function, the provider allocates memory for internal buffers and assigns a sequence value to identify this transaction. If you are no longer interested in a transaction, you must explicitly cancel the transaction by calling the OTCancelReply function. Calling this function allows the provider to free up the memory it has reserved and to reuse the sequence number associated with the canceled transaction.

If the function completes successfully, it returns the kOTNoErr result; it does not return any other kind of acknowledgment. It is your responsibility to deallocate memory that you have reserved for the address, options, and data buffers associated with the cancelled OTRcvRequest function.

Use the OTCancelReply function to cancel an incoming request; use the OTCancelRequest function to cancel an outgoing request.

VALID STATES

T_IDLE

SEE ALSO

You use the OTSndRequest function (page 3-137) to send a request.

You use the OTCancelRequest function (page 3-146) to cancel an outgoing request.