When a conversation is successfully allocated, VTAM® assigns a unique conversation identifier (CONVID) to it. This identifier is returned to the application program in the RPL6CNVD field of the RPL extension on completion of the APPCCMD CONTROL=ALLOC and APPCCMD CONTROL=RCVFMH5 macroinstructions.

The application program uses the conversation identifier to specify which conversation it will use when it issues conversation-based macroinstructions such as APPCCMD CONTROL=SEND or APPCCMD CONTROL=RECEIVE. For a complete list of the APPCCMDs that can specify a conversation identifier, see Keywords and returned parameters.