If you specify EFS control fields (D1 format) or EFS fields (D2 format), DFSORT calls the EFS01 or EFS02 exit routines, respectively, to process those fields. The routines are generated by your EFS program, which can return the following information about them at Major Call 3:

• The address of an extract routine, EFS01, which is used to extract the control fields of an input record to a buffer area before a sort or merge takes place; EFS01 is not applicable to a copy application.
• The address of an INCLUDE or OMIT routine, EFS02, which is used to process comparison logic for including or omitting records.