OSCaR commands are much simpler than the CA IDMS SEND/RECEIVE verb set for APPC cooperative processing in that they provide only a subset of the complete APPC functionality and synchronization of conversation states is automatic. It is not necessary to understand the CA IDMS SEND/RECEIVE verb set, the IBM APPC verb set, or Conversation States before using OSCaR commands. However, it is necessary to understand basic cooperative processing concepts.
OPEN, SEND, CLOSE, and RECEIVE (OSCaR) commands are an interface between mainframe CA ADS dialogs. OSCaR commands run as APPC commands; that is, as LU6.2 between mainframes. If a mainframe application is accessing a remote data base rather than a remote application, DDS should be more efficient.