Control statements will only be accepted at the initial execution of MAXSORT. If MAXSORT is restarted, the control statements cannot be changed. Except for JOIN, JOINKEYS, MERGE and REFORMAT, all MFX control statements are supported for MAXSORT. In addition, the RESTART subparameter of the SEQNUM parameter and the IFTHEN WHEN=GROUP parameter are not supported on an INREC statement.