WinCPICExtractEvent
The WinCPICExtractEvent function provides a method for an application to determine the event handle being used for a Microsoft® Windows® Common Programming Interface for Communications (CPI-C) conversation.
Syntax
VOID WINAPI WinCPICExtractEvent(
unsigned char FAR*conversation_ID,HANDLE FAR*event_handle, CM_INT32 FAR*return_code);
Parameters
conversation_ID
Specifies the identifier for the conversation for which this event is used. This parameter is returned by the initial Accept_Conversation call.
event_handle
Returned parameter. The handle of the event being used by this conversation. If no handle has been registered, this parameter returns as a NULL.
return_code
The code returned from this call. The valid return codes are listed later in this topic.
Return Codes
CM_OK
The function executed successfully.
CM_PROGRAM_PARAMETER_CHECK
One or more of the parameters passed to this function are invalid.
Remarks
When a verb is issued on a nonblocking conversation, it returns CM_OPERATION_INCOMPLETE if it is going to complete asynchronously. If an event has been registered with the conversation, the application can call WaitForSingleObject or WaitForMultipleObjects to be notified of the completion of the verb. WinCPICExtractEvent allows a CPI-C applicationto determine this event handle. When the verb has completed, the application must call Wait_For_Conversationto determine the return code for the asynchronous verb. The Cancel_Conversationfunction can be called to cancel an operation and conversation.
If no event has been registered, the asynchronous verb completes as it does at present, which is by posting a message to the window that the application has registered with the CPI-C library.