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• DISP parameter is USED for specifying the disposition of the data set.
• The current STATUS of the data set is specified at
  1. The beginning of the step.
  2. The successful EXECUTION of the step.
  3. Abnormal execution of the step.
• DISP is ASSIGNED for two dispositions ALONG with the status.
• The notation of DISP is DISP = (Status, Normal Disposition, Abnormal Disposition).

• Positional Parameters are placed in a specific POSITION.
• It needs to be positioned within the operand field.
• EXAMPLE: Employee name in the JOB card is a positional parameter at the Job level.
• Keyword Parameters are not placed in a specific position or ORDER.
• Example: MSGLEVEL=(X,Y)

• A library needs to be searched before the SYSTEM library, for locating programs to execute by STEPS.
• STEPLIB and JOBLIB are utilized for specifying the required library.
• Not all steps are applied for both STEPLIB and JOBLIB.
• STEPLIB is USED only for a particular step.
• JOBLIB is used for all the JOBS

• DISP NEW will allocate new memory space for disposition.
• DISP CATLG will catalog the available data set once the step is SUCCESSFUL.
• DISP KEEP will retain the dataset. Catalog will not be KEPT when the step abends.
• The above 3 operations ALWAYS ensures that the data set is properly HANDLED.
• The operations are RELIABLE to handle the data sets.

Addressing MODE or Access Mode:

• AMODE(24) INDICATES 24-BIT addressing in the memory below the line.
• AMODE(31) indicates 31-bit addressing in the memory above and below the line.
• AMODE=ANY indicates either 24-bit or 31-bit addressing techniques. Run Mode or Residency Mode:
• RMODE(24) indicates the program need to be loaded into the memory below the line.
• RMODE(31) indicates the program need to be loaded into the memory either below or above the line.
• RMODE=ANY indicates the program to load either in 24 bit or 31 bit memory.

Addressing mode or Access Mode:

• A language for JOB description to MVS, OS/390 and VSE Operating Systems that run on IBM S/390 servers.
• A set of statements that required for running a particular program is referred as a job step.
• Without user interaction, job runs in background.
• The OS manages the user requests to initiate the units of work.
• Input data sets, such as files are the specific JCL statements to access. Once the resources are allocated for the job, the OUTPUT data set is to be CREATED or updated.
• A set of JCL statements are stored as data set and will be started interactively.
• A menu-like interface is provided by MVS and OS/390, known as ISPF to initiate and manage JOBS.

Level describes the JCL statements. According to each action performed by each statement. Each statement of JCL consist of following keywords—

NAME.
FIELDS.
OPERATIONS.
OPERANDS.
PARAMETERS.

1. POSITIONAL.
2. KEYWORD.

COMMENTS IF ANY.

EG. //STEP007 EXEC PGM=JAMES BOND
Here stepoo7 is the name,
pgm is the keyword PARAMETER,
exec is the command,
assign is the OPERATION,
jamesbond is the OPERAND.

Level describes the JCL statements. According to each action performed by each statement. Each statement of JCL consist of following keywords—

NAME.
FIELDS.
OPERATIONS.
OPERANDS.
PARAMETERS.

COMMENTS IF ANY.

Eg. //STEP007 EXEC PGM=JAMES BOND
Here stepoo7 is the name,
pgm is the keyword parameter,
exec is the command,
assign is the operation,
jamesbond is the operand.

It is an important symbol USED in JCL statements. JCL statement must begin with this symbol. It is a predefined rule that must follow to execute the JCL statements OTHERWISE it will through error. The JCL execution system first checks for that symbol at BEGINNING of statements to be considered as JCL statement. Use without space between symbol and jobname. EVERY statement in jcl should start with //.to work properly. Use of it avoid any runtime exceptions.

It is an important symbol used in JCL statements. JCL statement must begin with this symbol. It is a predefined rule that must follow to execute the JCL statements otherwise it will through error. The JCL execution system first checks for that symbol at beginning of statements to be considered as JCL statement. Use without space between symbol and jobname. Every statement in jcl should start with //.to work properly. Use of it avoid any runtime exceptions.

There are certain set of divisions that INTERACT with JCL.

IDENTIFICATION Division- act as introductory part to JCL(program name, author,date etc no INTERACTING code).

Environment Division- now the story begins - JCL interacts with OS acc to NEED as it send request for Files under file operation.

Data Division- after files are accessed, it works with them according to operations to READ or to PRINT files (with the help of OS).

Procedure Division- it CONTAINS various actions taken on files eg to close files that are being used.

There are certain set of divisions that interact with JCL.

Identification Division- act as introductory part to JCL(program name, author,date etc no interacting code).

Environment Division- now the story begins - JCL interacts with OS acc to need as it send request for Files under file operation.

Data Division- after files are accessed, it works with them according to operations to READ or to PRINT files (with the help of OS).

Procedure Division- it contains various actions taken on files eg to close files that are being used.

The keywords ASSOCIATED with the DCB parameter are LRECL, RECFM, BLKSIZE and DSORG The DCB information can be supplied in the DD statement The system LOOKS for DCB information in the PROGRAM CODE FIRST

The keywords associated with the DCB parameter are LRECL, RECFM, BLKSIZE and DSORG The DCB information can be supplied in the DD statement The system looks for DCB information in the program code first

DATA SETS can be grouped in a DD statement ONE after another, eg in a JOBLIB statement where the LOAD module can EXIST in one of many Data Sets.

Data Sets can be grouped in a DD statement one after another, eg in a JOBLIB statement where the load module can exist in one of many Data Sets.

GDG stands for generation DATA group It is a Data Set with versions that can be referenced ABSOLUTELY or RELATIVELY It is defined by an IDCAMS DEFINE generation datagroup EXECUTION.

GDG stands for generation data group It is a Data Set with versions that can be referenced absolutely or relatively It is defined by an IDCAMS define generation datagroup execution.

PROC stands for procedure It is 'canned' JCL INVOKED by a PROC statement An INSTREAM PROC is presented WITHIN the JCL; a catalogued PROC is referenced from a proclib partitioned DATA Set.

PROC stands for procedure It is 'canned' JCL invoked by a PROC statement An instream PROC is presented within the JCL; a catalogued PROC is referenced from a proclib partitioned Data Set.

The DD STATEMENT links the EXTERNAL Data Set name (DSN) to the DDNAME coded within the EXECUTING program It links the File names within the program CODE to the File names know to the MVS operating system The syntax is // ddname DD DSN=Data Set name Other keywords after DSN are DISP, DCB, SPACE, etc .

The DD statement links the external Data Set name (DSN) to the DDNAME coded within the executing program It links the File names within the program code to the File names know to the MVS operating system The syntax is // ddname DD DSN=Data Set name Other keywords after DSN are DISP, DCB, SPACE, etc .

The EXEC STATEMENT identifies the program to be executed via a PGM=program NAME keyword Its format is //jobname EXEC PGM=program name The PARM= keyword can be USED to pass external VALUES to the executing program.

The EXEC statement identifies the program to be executed via a PGM=program name keyword Its format is //jobname EXEC PGM=program name The PARM= keyword can be used to pass external values to the executing program.

A keyword in a JCL statement MAY appear in different PLACES and is recognized by its name, eg MSGCLASS in the JOB statement The opposite is positional words, where their meaning is based on their POSITION in the statement, eg in the DISP keyword the =(NEW,CATLG,DELETE) meaning are based on first, second and third position.

A keyword in a JCL statement may appear in different places and is recognized by its name, eg MSGCLASS in the JOB statement The opposite is positional words, where their meaning is based on their position in the statement, eg in the DISP keyword the =(NEW,CATLG,DELETE) meaning are based on first, second and third position.

POSITIONAL PARAMETERS are CHARACTERIZED by their position in the operand field in relation to other parameters.

Keyword parameters are positional independent with respect to others of their type and CONSISTING of a keyword followed by an equal SIGN and variable information.

Positional parameters are characterized by their position in the operand field in relation to other parameters.

Keyword parameters are positional independent with respect to others of their type and consisting of a keyword followed by an equal sign and variable information.

DISP is a keyword parameter which is defined on the DD statement and which CONSIST of the FOLLOWING positional subparameters: DISP=(Status, Normal Disp, Abnormal Disp). The DISP parameter describes the current status of the dataset (old, new, or modified) and directs the system on the disposition of the data set (pass, keep, catalog, uncatalog, or DELETE) either at the END of the STEP or if the step abnormally terminates. DISP is always required unless the data set is created and deleted in the same step.

DISP is a keyword parameter which is defined on the DD statement and which consist of the following positional subparameters: DISP=(Status, Normal Disp, Abnormal Disp). The DISP parameter describes the current status of the dataset (old, new, or modified) and directs the system on the disposition of the data set (pass, keep, catalog, uncatalog, or delete) either at the end of the step or if the step abnormally terminates. DISP is always required unless the data set is created and deleted in the same step.

DISP=SHR permits old data SETS to be SHARED. SHR is identical to OLD except that several jobs may read the dataset concurrently in multiprogramming environments. SHR must be used only for input data sets; USE OLD or MOD if data set is modified. Sharing data set is necessary because public LIBRARIES like SYS1.LINKLIB or the subroutine libraries should be available to every JOB in the system.

DISP=SHR permits old data sets to be shared. SHR is identical to OLD except that several jobs may read the dataset concurrently in multiprogramming environments. SHR must be used only for input data sets; use OLD or MOD if data set is modified. Sharing data set is necessary because public libraries like SYS1.LINKLIB or the subroutine libraries should be available to every job in the system.

DISP=MOD modifies a sequential data set. It is a CONVENIENT way to add data to the END of sequential dataset. If the data set doesn’t exist, the system changes MOD to NEW UNLESS the VOL parameter request SPECIFIC volume. When VOL is coded, the stem expects to find data set on the specified volume and terminates the step if it cannot find it. MOD is the usual way of extended data sets in to several direct-access VOLUMES.

DISP=MOD modifies a sequential data set. It is a convenient way to add data to the end of sequential dataset. If the data set doesn’t exist, the system changes MOD to NEW unless the VOL parameter request specific volume. When VOL is coded, the stem expects to find data set on the specified volume and terminates the step if it cannot find it. MOD is the usual way of extended data sets in to several direct-access volumes.

PASS PASSES the data set on to subsequent job steps, and each step can use the data set once. It is a positional sub parameter of the DISP which could only be SPECIFIED under normal termination action. Pass SAVES time because the system retains the data set location and VOLUME information.

PASS passes the data set on to subsequent job steps, and each step can use the data set once. It is a positional sub parameter of the DISP which could only be specified under normal termination action. Pass saves time because the system retains the data set location and volume information.

The MINIMUM PARAMETERS NEEDED are DSN and DISP.

The minimum parameters needed are DSN and DISP.

DCB info comes from :-
1) PROGRAM – FD: BLOCK CONTAINS 3 RECORDS RECORD CONTAINS 100 CHARACTERS
2) The LABEL – like a TAPE
3) From the VTOC – for Dasd
4) From the JCL – DCB=BLKSIZE=nnn.

DCB info comes from :-
1) Program – FD: BLOCK CONTAINS 3 RECORDS RECORD CONTAINS 100 CHARACTERS
2) The label – like a tape
3) From the VTOC – for Dasd
4) From the JCL – DCB=BLKSIZE=nnn.

LABEL is a KEYWORD parameter which can be specified on DD statement and consists of the FOLLOWING subparameters:

LABEL=(RELATIVE File #, Type of Label Processing)
The LABEL parameter tells the type of label, the relative file number,and WHETHER the data set is to be protected for input or OUTPUT.

LABEL is a keyword parameter which can be specified on DD statement and consists of the following subparameters:

LABEL=(Relative File #, Type of Label Processing)
The LABEL parameter tells the type of label, the relative file number,and whether the data set is to be protected for input or output.

NL should be specified when a program needs to process unlabeled tapes NL can also be specified when the program wants to create unlabeled TAPE because the system’s default action, in cases when parameter is not specified, will create IBM standard label. Non labeled tapes are often used for sending tapes to another installation. That way you don’t have to worry about the tape label corresponding to the STANDARDS at the other installation or about ACCIDENTALLY matching the volume serial number of an existing tape at the installation.

NL should be specified when a program needs to process unlabeled tapes NL can also be specified when the program wants to create unlabeled tape because the system’s default action, in cases when parameter is not specified, will create IBM standard label. Non labeled tapes are often used for sending tapes to another installation. That way you don’t have to worry about the tape label corresponding to the standards at the other installation or about accidentally matching the volume serial number of an existing tape at the installation.

You should USE EITHER DD * or DD DATA.

You should use either DD * or DD Data.

DD * and DD DATA describe the INPUT data which follows the above MENTION cards. If the input data contains RECORD switch // in col 1 and 2 then DD Data should be used.

DD * and DD DATA describe the input data which follows the above mention cards. If the input data contains record switch // in col 1 and 2 then DD Data should be used.

It is a KEYWORD parameter which should allocated on the DD statement for the OUTPUT data SETS stored on the DISK. It consists of the following sub parameters:
SPACE=(BLKS/CYL/TRK,(primary,secondary,index),RLSE,CONTIG)

It is a keyword parameter which should allocated on the DD statement for the output data sets stored on the disk. It consists of the following sub parameters:
SPACE=(BLKS/CYL/TRK,(primary,secondary,index),RLSE,CONTIG)

RLSE releases all unused SPACE when the data SET is closed. It permits you to ALLOCATE more space than perhaps, it needed WITHOUT WASTING space. Space is released only if the data set is not empty and if the data set is closed after being opened.

RLSE releases all unused space when the data set is closed. It permits you to allocate more space than perhaps, it needed without wasting space. Space is released only if the data set is not empty and if the data set is closed after being opened.

CONTIG requests the primary space be allocated only on contiguous tracks and CYLINDERS that are all tracks on a cylinder are contiguous, and if more than one cylinder is NEEDED, the cylinders are ALSO contiguous. Always code CONTIG if TRACK overflow is used.

CONTIG requests the primary space be allocated only on contiguous tracks and cylinders that are all tracks on a cylinder are contiguous, and if more than one cylinder is needed, the cylinders are also contiguous. Always code CONTIG if track overflow is used.

PDS is a LIBRARY type of DATA set organization CONSISTING of Directory and Members. The directory consists of blocks, and each block is 256 bytes in length and can hold up to 5 members. Each member of the PDS is a SEQUENTIAL data set.

PDS is a library type of data set organization consisting of Directory and Members. The directory consists of blocks, and each block is 256 bytes in length and can hold up to 5 members. Each member of the PDS is a sequential data set.

Temporary data sets are used for storage needed only for the duration of the job. If the DISP parameter doesn’t DELETE the data set by the END of the job, the system will delete it. Deleting a tape data set dismounts the tape, whereas deleting a dataset on a direct-access VOLUME release the storage. A data set is marked temporary by omitting the DSN parameter or by coding DSN=&&dsname. The system ASSIGN a UNIQUE name to the data set when the DSN parameter is omitted, and any subsequent steps using the dataset refer back to the DD statement.

Temporary data sets are used for storage needed only for the duration of the job. If the DISP parameter doesn’t delete the data set by the end of the job, the system will delete it. Deleting a tape data set dismounts the tape, whereas deleting a dataset on a direct-access volume release the storage. A data set is marked temporary by omitting the DSN parameter or by coding DSN=&&dsname. The system assign a unique name to the data set when the DSN parameter is omitted, and any subsequent steps using the dataset refer back to the DD statement.

It is a keyword parameter which can be specified on the JOB or EXEC statements. COND CONSISTS of 3 sub PARAMETERS:

code(0 THRU 4095),LOGICAL operator, and step NAME of the step that is going to be compared.
The purpose of the COND is to determine whether the step should be executed or bypassed. If condition specified in the COND parameter is true, the step is bypassed.

It is a keyword parameter which can be specified on the JOB or EXEC statements. COND consists of 3 sub parameters:

code(0 thru 4095),logical operator, and step name of the step that is going to be compared.
The purpose of the COND is to determine whether the step should be executed or bypassed. If condition specified in the COND parameter is true, the step is bypassed.

COND=(0,LE) or COND=(4095,GE).

COND=(0,LE) or COND=(4095,GE).

It means that this job STEP will be EXECUTED only if a previous step had ABNORMALLY terminated.

It means that this job step will be executed only if a previous step had abnormally terminated.

It means that this jobs STEP will be executed EVEN if a PREVIOUS step abnormally TERMINATED.

It means that this jobs step will be executed even if a previous step abnormally terminated.

Name is a POSITIONAL parameter which identifies the person or GROUP RESPONSIBLE for a JOB.

Name is a positional parameter which identifies the person or group responsible for a job.

It is a keyword parameter which specifies a job initiation priority within its job class. When the job is initiated, the SYSTEM will convert the job’s priority into a dispatching priority so that job’s task can complete with other tasks for use of MAIN storage and CPU RESOURCES.

It is a keyword parameter which specifies a job initiation priority within its job class. When the job is initiated, the system will convert the job’s priority into a dispatching priority so that job’s task can complete with other tasks for use of main storage and CPU resources.

First the SYSTEM determines which JOB has the highest class. Each class has a job QUEUE with JOBS of different priorities. The system will select the job for execution that has the highest PRTY (0 thru 15) 15 is the highest priority.

First the system determines which job has the highest class. Each class has a job queue with jobs of different priorities. The system will select the job for execution that has the highest PRTY (0 thru 15) 15 is the highest priority.

It is a keyword parameter which specifies the output CLASS to which system messages for your JOB are to be routed. Output class is an alphabetic (A THRU Z) or numeric (0 thru 9) CHARACTER. The default for MSGCLASS parameter will be A. System messages and output data sets can be routed to the same output class. You can code the MSGCLASS parameter in the Job statement and the SYSOUT parameter on the DD statement.

It is a keyword parameter which specifies the output class to which system messages for your job are to be routed. Output class is an alphabetic (A thru Z) or numeric (0 thru 9) character. The default for MSGCLASS parameter will be A. System messages and output data sets can be routed to the same output class. You can code the MSGCLASS parameter in the Job statement and the SYSOUT parameter on the DD statement.

It is a keyword parameter which indicates what job output is to be written as a part of output listing. The following outputs can be requested: the Job statement;
all INPUT job control statements;
allocation, DISPOSITION and allocation recovery messages(allocation/termination MESSAGE)

MSGLEVEL=(statements, messages)

Statements:
- 0 – only the job statement is to be written;
- 1 – all input control statements, cataloged procedure statements and the INTERNAL representation of procedure statement parameters after symbolic parameters substitution are to be written;
- 2 – only input job control statements are to be written;

Messages:
- 0 – No allocation/termination messages are to be PRINTED unless the job terminates abnormally;
- 1 – All allocation/termination messages are to be printed.

It is a keyword parameter which indicates what job output is to be written as a part of output listing. The following outputs can be requested: the Job statement;
all input job control statements;
allocation, disposition and allocation recovery messages(allocation/termination message)

MSGLEVEL=(statements, messages)

Statements:
- 0 – only the job statement is to be written;
- 1 – all input control statements, cataloged procedure statements and the internal representation of procedure statement parameters after symbolic parameters substitution are to be written;
- 2 – only input job control statements are to be written;

Messages:
- 0 – No allocation/termination messages are to be printed unless the job terminates abnormally;
- 1 – All allocation/termination messages are to be printed.

TYPRUN=SCAN should be SPECIFIED on a JOB CARD

TYPRUN=SCAN should be specified on a job card

COND PARAMETER specified on EXEC statement determines whether step should be bypassed or executed.

COND parameter defined on the JOB statement will DETERMINE whether Job should be terminated at a certain point or continued. When COND parameter is defined on the JOB statement, the system evaluates condition specified in the COND parameter before beginning of any job step and COMPARES the code specified in the COND parameter with the return code of all previous jobsteps. If that condition is true, the rest of the job STEPS are bypassed.

COND parameter specified on EXEC statement determines whether step should be bypassed or executed.

COND parameter defined on the JOB statement will determine whether Job should be terminated at a certain point or continued. When COND parameter is defined on the JOB statement, the system evaluates condition specified in the COND parameter before beginning of any job step and compares the code specified in the COND parameter with the return code of all previous jobsteps. If that condition is true, the rest of the job steps are bypassed.

SECONDARY ALLOCATION is done when more space is required than what has ALREADY been allocated.

Secondary allocation is done when more space is required than what has already been allocated.

The SPACE ALLOCATED when the DATASET is FIRST CREATED.

The space allocated when the dataset is first created.

16 EXTENTS on a volume for a SEQUENTIAL file and 123 for a VSAM file.

16 extents on a volume for a sequential file and 123 for a VSAM file.

That this is a NEW dataset and NEEDS to be allocated, to CATLG the dataset if the STEP is SUCCESSFUL and to delete the dataset if the step abends.

That this is a new dataset and needs to be allocated, to CATLG the dataset if the step is successful and to delete the dataset if the step abends.

That this is a new dataset and needs to be allocated, to CATLG the dataset if the step is successful and to KEEP but not CATLG the dataset if the step abends. Thus if the step abends, the dataset would not be catalogued and we would need to SUPPLY the vol. ser the NEXT TIME we refer to it.

That this is a new dataset and needs to be allocated, to CATLG the dataset if the step is successful and to KEEP but not CATLG the dataset if the step abends. Thus if the step abends, the dataset would not be catalogued and we would need to supply the vol. ser the next time we refer to it.

NEED to SUPPLY VOLUME SERIAL no. VOL=SER=xxxx.

Need to supply volume serial no. VOL=SER=xxxx.

The MOD will CAUSE the dataset to be CREATED (if it does not exist), and then the two DELETEs will cause the dataset to be deleted whether the STEP abends or not. This disposition is used to CLEAR out a dataset at the beginning of a job.

The MOD will cause the dataset to be created (if it does not exist), and then the two DELETEs will cause the dataset to be deleted whether the step abends or not. This disposition is used to clear out a dataset at the beginning of a job.