Scenario - Create three output files by splitting 4 records each.

Input File - MATEPK.SORT.INPUT01 - FB file of 80 length

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00001     student1           dept1          560
00003     student3           dept2          520
00004     student4           dept1          540
00005     student5           dept2          500
00002     student2           dept3          510
00006     student6           dept3          550
00008     student8           dept1          530
00007     student7           dept3          510
00009     student9           dept2          520
00010     student10          dept2          505

JCL -

----+----1----+----2----+----3----+----4----+----5----+----6----+----7--
//MATEPKD  JOB (123),'MTH',NOTIFY=&SYSUID
//*
//STEP01   EXEC PGM=SORT
//SORTIN   DD DSN=MATEPK.SORT.INPUT01,DISP=SHR
//OUTPUT1  DD DSN=MATEPK.SORT.OUTPT01,
//             SPACE=(CYL,(1,1),RLSE),DCB=*.SORTIN, 
//             DISP=(NEW,CATLG,DELETE)
//OUTPUT2  DD DSN=MATEPK.SORT.OUTPT02,
//             SPACE=(CYL,(1,1),RLSE),DCB=*.SORTIN, 
//             DISP=(NEW,CATLG,DELETE)
//OUTPUT3  DD DSN=MATEPK.SORT.OUTPT03,
//             SPACE=(CYL,(1,1),RLSE),DCB=*.SORTIN,
//             DISP=(NEW,CATLG,DELETE)
//SYSOUT   DD SYSOUT=*
//SYSIN    DD *
     SORT FIELDS=(1,5,ZD,A)
     OUTFIL FNAMES=(OUTPUT1,OUTPUT2,OUTPUT3),SPLITBY=4 
/*

Output File1 - MATEPK.SORT.OUTPT01 - FB file of 80 length

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00001     student1           dept1          560
00002     student2           dept3          510
00003     student3           dept2          520
00004     student4           dept1          540

Output File2 - MATEPK.SORT.OUTPT02 - FB file of 80 length

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00005     student5           dept2          500
00006     student6           dept3          550
00007     student7           dept3          510
00008     student8           dept1          530

Output File3 - MATEPK.SORT.OUTPT03 - FB file of 80 length

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00009     student9           dept2          520
00010     student10          dept2          505

Explaining Example -

1. SORT FIELDS=(1,5,ZD,A) - sort all outputs in ascending order based on the ZD value from 1 to 5 positions.
2. OUTFIL FNAMES=(OUTPUT1,OUTPUT2,OUTPUT3),SPLITBY=4 - Splits the records by 4. First 4 records to output1 file, next 4 records to Output2 file and next 4 to output3 file.
3. If any more records than 12, then the above process will occur again and again until it reaches to file end.

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