Subparameter definition

PROGRAM
Indicates that each logical record in the data set begins with a carriage control character, which must be identified in the DD statement, DCB macro, or data set label. You might identify these carriage control characters in the DD statement through the DCB subparameter in the RECFM of the data set as being A (ASA) or M (machine). The carriage control characters are given in z/OS DFSMS Using Data Sets.
SINGLE
Indicates forced single spacing.
DOUBLE
Indicates forced double spacing.
TRIPLE
Indicates forced triple spacing.