DFSORT makes five functional calls (Major Calls 1 through 5) at various phases to transfer information across the EFS interface, between DFSORT and your EFS program. DFSORT can make multiple calls at Major Calls 2 and 3. Refer to Figure 1 and Figure 2 as you read this section for illustrations of the relationships between program phases and calls during run-time.

Figure 1. EFS Program Calls for a Sort. The figure also shows the calls to the EFS program EFS01 and EFS02 exit routines.

Figure 2. EFS Program Calls for a Merge or Copy. The figure also shows the calls to the EFS program EFS01 and EFS02 exit routines.