JCL PROC Statement Override

When an entire JCL PROC statement needs to be replaced, then a JCL PROC override statement can be used. An override statement has the following form:

//stepname.ddname DD ...

Sample procedure with statement override shows an example of overriding the SORTOUT DD statement in MYPROC . Here, SORTOUT is directed to a newly created sequential data set.

Sample procedure with statement override

//MYJOBJOB 1

 //*---------------------------------*

 //MYPROCPROC

 //MYSORTEXEC PGM=SORT

 //SORTINDD DISP=SHR,DSN=&SORTDSN

 //SORTOUTDD SYSOUT=*

 //SYSOUTDD SYSOUT=*

 //PEND

 //*---------------------------------*

//STEP1EXEC MYPROC,SORTDSN=ZPROF

.AREA.CODES 

//MYSORT.SORTOUT DD DSN=ZPROF

.MYSORT.OUTPUT, 

//DISP=(NEW,CATLG),SPACE=(CYL,(1,1)),

 //UNIT=SYSDA,VOL=SER=SHARED,

 //DCB=(LRECL=20,BLKSIZE=0,RECFM=FB,DSORG=PS)

 //SYSINDD *

SORT FIELDS=(1,3,CH,A)

How is a job submitted for batch processing?
Using UNIX as an analogy, a UNIX process can be processed in the background by appending an 
ampersand (&) to the end of a command or script. Pressing Enter then submits the work as a background 
process.
In z/OS terminology, work (a job) is submitted for batch processing. Batch processing is a rough 
equivalent to UNIX background processing. The job runs independently of the interactive session.
The term batch is used because it is a large collection of jobs that can be queued, waiting their turn to 
be executed when the needed resources are available. Commands to submit jobs might take any of the 
following forms:
ISPF editor command line
Submit and press Enter.
ISPF command shell SUBmit `USER.JCL'
where the data set is sequential.
ISPF command line TSO SUBmit 'USER.JCL '

where the data set is sequential.
ISPF command line TSO SUBmit `USER.JCL(MYJOB)'

where the data set is a library or partitioned data set containing member MYJOB.
TSO command line SUBmit 'USER.JCL '
Several ways to submit a JCL stream for processing shows three different points at which you can 
enter the SUBMIT command.