COBOL E15 user exit: passing or changing records for sort

The EXITCK option affects the way DFSORT interprets certain return codes from user exit E15. To avoid ambiguity, this section assumes that the IBM default, EXITCK=STRONG, was selected at your site. For complete information about E15 return codes in various situations with EXITCK=STRONG and EXITCK=WEAK, see E15/E35 return codes and EXITCK.

DFSORT enters the E15 user exit routine each time a new record is brought into the input phase. DFSORT continues to enter E15 (even when there are no input records) until the user exit tells DFSORT, with a return code of 8, not to return.

See Figure 1 for logic flow details.

Some uses for the E15 user exit are:

Adding records to an input data set
Passing an entire input data set to DFSORT
Deleting records from an input data set
Changing records in an input data set.

Note:

If both E15 and E35 user exits are used, they must be in the same version of COBOL.
If you use the E15 user exit to pass all your records to DFSORT, you can omit the SORTIN DD statement, in which case you must include a RECORD statement in the program control statements.
If you omit the SORTIN DD statement, all input records are passed to DFSORT through your COBOL E15 user exit. You return to DFSORT with a return code of 12. When DFSORT returns to the E15 user exit after the last record has been passed, you return to DFSORT with a return code of 8 in register 15, which indicates "do not return."
DFSORT continues to reenter your E15 user exit until a return code of 8 is received. However, if STOPAFT is in effect, no additional records are inserted to DFSORT after the STOPAFT count is satisfied (even if you pass back a return code of 12).
You cannot use dynamic binding or link-editing with a COBOL E15 user exit.