When required

Each ddname specified in an OUTFIL statement requires a corresponding DD statement for that OUTFIL data set.

If you do not specify OUTFIL statements, a SORTOUT DD statement is required unless you provide an E35 user exit that disposes of all output. A SORTOUT DD statement is ignored if your program invokes DFSORT and passes the address of an E35 user exit in the parameter list.

If you specify OUTFIL statements, you do not have to specify a SORTOUT DD statement or an E35 user exit, although you can use either or both.