Scenario - Replace the "dept" with "department".

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

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00001     student1           dept           560       01012015
00003     student3           dept           520       03032015
00004     student4           dept           540       06022015
00005     student5           dept           500       09202015
00002     student2           dept           510       05182015

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
//SORTOUT   DD DSN=MATEPK.MERGE.OUTPUT,
//            DISP=(NEW,CATLG,DELETE),UNIT=SYSDA,
//            SPACE=(CYL,(1,4),RLSE),
//            DCB=(RECFM=FB,LRECL=80,BLKSIZE=0)
//SYSOUT   DD SYSOUT=*
//SYSIN    DD *
     SORT FIELDS=(1,5,CH,A)
     OUTREC FIELDS=(1,29,30,4,CHANGE=(12,C'dept',C'department'),
                    5X,45,30)
/*

Output -

----+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8
00001     student1           department       560       01012015
00002     student2           department       510       05182015
00003     student3           department       520       03032015
00004     student4           department       540       06022015
00005     student5           department       500       09202015

Explaining Example -

1. OUTREC FIELDS=(1,29,..) - Copies the first 29 bytes of data from input file to output as it is.
2. OUTREC FIELDS=(..,30,4,CHANGE=(12,C'dept',C'department'),..) - The "dept" text starting from 30th byte of length 4 in the input file should replace with "department" of length 12 while writing it to output file.
3. OUTREC FIELDS=(..,5X,..) - add 5 spaces from 40th byte.
4. OUTREC FIELDS=(..,45,30) - copies the input file data from 45th byte of length 30 as it is to output starts at 45th byte.

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