Author: admin

The Job Entry System uses two approaches to perform conditional processing in a JCL. When a job completes, a return code is set based on the status of execution. The return code can be a number between 0 (successful execution) to 4095 (non-zero shows error condition). The most common conventional values are: A job step…

The JCL Procedures are set of statements inside a JCL grouped together to perform a particular function. Usually, the fixed part of the JCL is coded in a procedure. The varying part of the Job is coded within the JCL. You can use a procedure to achieve parallel execution of a program using multiple input files. A…

Base Library is the Partitioned Dataset (PDS), which holds the load modules of the program to be executed in the JCL or the catalogued procedure, which is called in the program. Base libraries can be specified for the whole JCL in a JOBLIB library or for a particular job step in a STEPLIB statement. JOBLIB Statement A JOBLIB statement is used in…

Datasets are mainframe files with records organised in a specific format. Datasets are stored on the Direct Access Storage Device (DASD) or Tapes of the mainframe and are basic data storage areas. If these data are required to be used/created in a batch program, then the file (i.e., dataset) physical name along with the file…

Each JCL can be made of many job steps. Each job step can execute a program directly or can call a procedure, which in turn executes one or more programs (job steps). The statement, which holds the job step program/procedure information is the EXEC statement. The purpose of the EXEC statement is to provide required information…

JOB Statement is the first control statement in a JCL. This gives the identity of the job to the Operating System (OS), in the spool and in the scheduler. The parameters in the JOB statement help the Operating Systems in allocating the right scheduler, required CPU time and issuing notifications to the user. Syntax Following…

Installing JCL on Windows/Linux There are many Free Mainframe Emulators available for Windows which can be used to write and learn sample JCLs. One such emulator is Hercules, which can be easily installed in Windows by following few simple steps given below: Hercules is an open source software implementation of the mainframe System/370 and ESA/390…

When to use JCL JCL is used in a mainframe environment to act as a communication between a program (Example: COBOL, Assembler or PL/I) and the operating system. In a mainframe environment, programs can be executed in batch and online mode. Example of a batch system can be processing the bank transactions through a VSAM…