JCL Tutorials: Features and Practical Examples

Welcome to our JCL (Job Control Language) programming tutorial portal! Here at cobolcoder.com, we are dedicated to providing you with detailed and accessible resources to help you master JCL and optimize your workflows in mainframe environments.

What is JCL? Job Control Language (JCL) is essential in the world of mainframes, as it allows the definition and management of task and program execution in operating systems like IBM z/OS. On our platform, you will find a series of step-by-step tutorials designed to help you understand the fundamentals of JCL, from job creation to resource management and performance optimization.

Dive into the fascinating world of JCL with us! Explore our tutorials, participate in the community, and take your mainframe programming skills to the next level. We are excited to be a part of your JCL learning journey!

Table of contents

Basic Guides to Programming in JCL

SORT in JCL

In JCL (Job Control Language), you can use the SORT program to sort two files.

//SORTJOB JOB (123),'Nombre del job',CLASS=A,MSGCLASS=X,MSGLEVEL=(1,1) 
//STEP1 EXEC PGM=SORT 
//SYSOUT DD SYSOUT=A 
//SORTIN1 DD DSN=your.input.file1,DISP=SHR 
//SORTIN2 DD DSN=your.input.file2,DISP=SHR 
//SORTOUT DD DSN=your.output.file,DISP=(NEW,CATLG,DELETE), 
//           UNIT=SYSDA,SPACE=(CYL,(5,5),RLSE) 
//SYSIN DD * SORT FIELDS=(start_position,length,format,A/D) /*

This article explains its main features with programming examples.

SUM FIELDS

The SUM FIELDS JCL statement indicates that when two records have equal control fields in a SORT or merge operation, the summary fields are summed, the sum is placed in one of the records, and the other is deleted. If the EQUALS option is activated, the first record is retained; if the NOEQUALS option is activated, the retained record is unpredictable.

//SORTJOB JOB ...
//STEP1 EXEC PGM=SORT
//SYSOUT DD SYSOUT=*
//SORTIN DD DSN=input.dataset,DISP=SHR
//SORTOUT DD DSN=output.dataset,DISP=(NEW,CATLG,DELETE),
//            UNIT=SYSDA,SPACE=(CYL,(5,5)),DCB=(RECFM=FB,LRECL=80)
//SYSIN DD *
  SORT FIELDS=(1,3,CH,A)
  SUM FIELDS=(10,3,ZD),FORMAT=BI
/*

The following entry details and explains its main features with examples and illustrations.

INCLUDE Condition – SORT in JCL

In JCL (Job Control Language), the INCLUDE condition is used in the context of the SORT step to specify a set of records that should be included in the output of the sorting step. The INCLUDE clause helps filter records based on specific criteria, retaining only those that meet the condition. Here’s a basic layout and explanation of the INCLUDE condition’s features:

//SORTJOB  JOB  (123),'Sort with INCLUDE',CLASS=A,MSGCLASS=X,MSGLEVEL=(1,1)
//STEP1    EXEC PGM=SORT
//SYSOUT   DD  SYSOUT=A
//SORTIN   DD  DSN=your.input.file,DISP=SHR
//SORTOUT  DD  DSN=your.output.file,DISP=(NEW,CATLG,DELETE),
//             UNIT=SYSDA,SPACE=(CYL,(5,5),RLSE)
//SYSIN    DD  *
  SORT FIELDS=(1,10,A)
  INCLUDE COND=(11,2,CH,EQ,C'20')
/*

In this example, the INCLUDE condition is used to include only the records that meet the specified condition. In this case, records where the content in positions 11 and 12 is equal to ’20’.

OUTFIL in JCL: SORT to Divide a File

The OUTFIL in JCL is used with the SORT utility to create multiple output files from a single input file, based on specific criteria. This process is highly useful when we want to divide records in a file according to a certain condition, such as status, type, or any other identifying field. In this example, we’ll cover how to use OUTFIL in JCL SORT to split a file based on a particular position and value.

Below is a JCL example using SORT to divide USER.FILE.ALL into two files: USER.FILE.STUDENTS for students and USER.FILE.TEACHERS for teachers.

//SPLITFILE JOB (ACCT),'Divide Files',CLASS=A,MSGCLASS=X
//STEP1     EXEC PGM=SORT
//SYSPRINT  DD SYSOUT=*
//SORTIN    DD DSN=USER.FILE.ALL,DISP=SHR
//STUDENTS  DD DSN=USER.FILE.STUDENTS,DISP=(NEW,CATLG,DELETE),
//          UNIT=SYSDA,SPACE=(CYL,(5,5),RLSE),
//          DCB=(RECFM=FB,LRECL=80,BLKSIZE=0)
//TEACHERS  DD DSN=USER.FILE.TEACHERS,DISP=(NEW,CATLG,DELETE),
//          UNIT=SYSDA,SPACE=(CYL,(5,5),RLSE),
//          DCB=(RECFM=FB,LRECL=80,BLKSIZE=0)
//SYSOUT    DD SYSOUT=*
//SYSIN     DD *
  SORT FIELDS=COPY
  OUTFIL FNAMES=STUDENTS,INCLUDE=(26,8,CH,EQ,C'STUDENT')
  OUTFIL FNAMES=TEACHERS,INCLUDE=(26,8,CH,EQ,C'TEACHER')
/*

After running this JCL, USER.FILE.STUDENTS will contain records with “STUDENT” in the specified position, and USER.FILE.TEACHERS will contain records with “TEACHER” in that same position.

This page provides a comprehensive introduction to JCL (Job Control Language), covering essential features, practical examples, and key functionality used in mainframe environments. By exploring concepts like job structure, data handling, and common utilities, readers gain practical knowledge to effectively manage batch processing tasks. With detailed examples, this guide equips beginners and experienced users alike with the tools to optimize JCL for real-world scenarios.