When an unknown descriptor is specified for conversational services, the tpsend(), tprecv(), and tpdiscon() functions return TPEBADDESC.

When tpsend() and tprecv() fail with a TPEEVENT error after a conversational connection is established, an event has occurred. Data may or may not be sent by tpsend(), depending on the event. The system returns TPEEVENT in the revent parameter passed to the function call and the course of action is dictated by the particular event.

For a complete description of conversational events, refer to Understanding Conversational Communication Events .