HP-UX SNAplus2 CPI-C Programmer's Guide (June 2003)

CPI-C Calls

Cancel_Conversation (cmcanc)

Chapter 3 129

End of Section

Cancel_Conversation (cmcanc)

The Cancel_Conversation call ends a speciﬁed conversation, canceling

any incomplete operation (a previous call that returned with

CM_OPERATION_INCOMPLETE) on this conversation, and ends the session

that the conversation was using. It is equivalent to the Deallocate call

with the

deallocate_type

parameter set to CM_DEALLOCATE_ABEND,

with the following differences:

• Deallocate cannot be used while an operation is incomplete;

Cancel_Conversation can be used, and will cancel the outstanding

call.

• Deallocate writes the log data, if any, to the local error log;

Cancel_Conversation does not.

The results of the outstanding call are undeﬁned, and will not be

returned to the application. For example, if Cancel_Conversation is used

to cancel an outstanding Send_Data call, some or all of the data may

have been sent; if it is used to cancel Send_Error, an error indication may

or may not have been sent to the partner program.

In Java CPI-C, nonblocking calls are not supported and so there cannot

be an incomplete call outstanding. Cancel_Conversation is equivalent to

Deallocate except that it does not write log data to the local error log.

Function Call

void cmcanc (

unsigned char CM_PTR conversation_ID,

CM_RETURN_CODE CM_PTR return_code

);