The SPLIT1R=n parameter of the OUTFIL control statement causes all output records to be grouped and distributed among files in an OUTFIL group in a single rotation to maintain contiguity. The first n records are written to the first output file followed by the next n records written to the next output file and so on, with the remaining records written to the last output file regardless of n. The value of n must be specified.
SPLIT, SPLITBY=n and SPLIT1R=n are mutually exclusive.
For the above example, given 36 records to be distributed in a single rotation, records 1 to 10 will be written to the first data set; records 11 to 20 will be written to the second data set; and records 21 to 36 will be written to the third data set.