Running an Advise Loop

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A DDE client can express interest in a particular item maintained by the DDE server by starting an advise loop for that item. The server notifies the client whenever that item changes, as long as the client has not stopped the advise loop. You may run only one advise loop for each item in a particular conversation.

To start an advise loop from USoft Developer, call:

DdeStartAdvise( service, topic, item, format, resource )


Service and topic uniquely identify the current conversation, which must have been started with:

DdeConnect( servicetopic )


and may not have been finished with

DdeDisconnect( servicetopic )


Item is the item in which the client wants to express an interest.

Format is the format in which it should be delivered.

Resource is the resource of the current object that should be set to the value returned by the call to DdeRequest(). At this moment, only the "value" resource is supported. This means that DdeRequest() can only be used to set a value in the current field. This may be the field from which this action is called or the client of the decision calling this action.

To stop a running advise loop, call:

DdeStopAdvise( service, topic, item )


Service and topic identify the current conversation. Item is the item in which the client expressed interest.