A complete overview on JCL and its concepts...by rohitkapa

1. JOB CONTROL
LANGUAGE
Complete Overview

2. Session Objectives
 To understand the
 Job Control Language
 Introduction
 Overview
 JOB, EXEC and DD (Data Definition) Statements
 Syntax of the various statements
 Execution process
2

3. Sessions Outline
 Session 1 : Introduction to JCL
 Session 2 : JOB Statement
 Session 3 : EXEC Statement
 Session 4 : DD Statement
 Session 5 : Job Processing Overview
 Session 6 : Program Execution
3

4. Introduction to JCL
Session 1
4

5. Job Control Language (JCL)
 Describes to the
operating system the
work that has to be done
and the resources
required to do the work
MVS
5

6. Need for JCL
OS
Accounting Info Resources
Program
Region size
Job details
Priority
JCL
6

7. JCL Features
 Consists of a set of statements called as Job Control Statements
 Group of related JCL statements is known as Job
 JCL consists of one or more Jobs
 Job consists of Job steps to execute the instructions (tasks)
7

8. Job Control Task
 Job Control Tasks,
 Entering Jobs
 Processing Jobs
 Requesting Resources
are performed through,
 JCL Statements
 JES2 / JES3 Control Statements
8

9. Job Entry Subsystem
 Receive jobs into the operating system and schedule them for processing
 Manages the output processing of the job (spooling)
 JES2 and JES3 are the two JES types provided by IBM
 JES2/JES3 subsystems are part of the OS that manages Batch jobs and
Output
9

10. Job Submission Process
USER ACTIONS SYSTEM ACTIONS
Determine Create Submit JES interprets
the the the JCL & Passes
Job JCL Job it to MVS
System MVS does
Messages the work
JES Collects
User views &
the output &
interprets the
information about
output
the job
10

11. JCL Statement Syntax
Identifier
field
//NAME OPERATION OPERAND COMMENTS
Name Operation Operand / Comment
field field Parameter field
field
11

12. Identifier Field
 Identifier field indicates to the system that a statement is a JCL
rather than data
 Code the Identifier field beginning in column 1
 Consists of
 Column 1 and 2 of all the JCL statements (//)
 Column 1 2 and 3 of a JCL statement ( //* for comment)
 Column 1 and 2 to mark end of data (/*)
12

13. Name field
 Identifies a particular statement so that the other statements and
the system can refer it
 Syntax
 name should start in column 3
 name is 1 through 8 alphanumeric
 name should be followed by a blank
 first character should be a alphabetic or national ( $, #, @)
13

14. Operation Field
 Specifies the type of the statement
 Consists of characters in the syntax box for the statement
 Follows the name field
 Operation must be followed and preceded by at least one blank
 Must begin on or before column 16
14

15. Parameter or Operand Field
 Also called as Operand field
 Must end before column 62
 Contains parameters separated by commas
 Positional and Keyword Parameters. An eg.
//RT452216 JOB 45992,CLASS=A
 All positional parameters must precede all keyword parameters
 Subparameters may be coded under Parameters to add further
meaning to the statement An eg.
//RT452216 JOB (45992,100,40),COND=(9,LT)
15

16. Comment Field
 Used to enter a comment in the output listing
 Used to document a job and its resource requirements
 Can be placed anywhere after the job statement
 Appears as //* in Column 1, 2 and 3
 Comment field can be coded till Column 80
16

17. JCL Statements - Basics
 Code the Operation, Operand and Comments fields in free form
with at least one blank in-between
 Code the Name field immediately after the Identifier without any
blank column
 All fields except for Operand must be separated by one blank
 Only Columns 1 to 71 are used for JCL Content
 Is case sensitive (Lower case not permitted)
17

18. JCL Statements – Basics (Contd.)
 Statements can be continued in
the next line with // in 1 & 2
columns
 The continued line must start
between columns 4 and 16
 Marking the end of the JCL is
optional
18

19. JCL Example
19

20. JCL Statements - Essential
 Each Job is identified by a JOB statement that marks the beginning
of a Job
 Every job has one and only one job statement
 Each Exec step is identified by an EXEC statement
 EXEC (Execute) Statements follow the JOB Statement and has
the name of the Programs / PROC’s to execute
20

21. JCL Statements – Essential (Contd.)
 Each Exec step may contain one or more control statements (DD
statements) to describe resources required for the Job step
 DD Statements describe each data set & request the allocation
of I/O devices
 Code the comment (//*) Statement to document the JCL
 Code the delimiter (/*) Statement for marking the end-of-data for
in-stream data
21

22. JCL Statements - Optional
 IF / THEN / ELSE / ENDIF Statement for selective execution of a Job
Step
 SET Statement assigns symbolic parameter values
 INCLUDE Statement to copy JCL from a file into Job Stream
 PROC & PEND Statements mark the beginning and end of a
Procedure (Cataloged / in-stream)
 JCLLIB Statement names the PROC & JCL Data set
22

23. IF/THEN/ELSE/ENDIF
 Used to conditionally execute job step with job
 Examples:
//NAME IF (RC GT 4) THEN
To Test if RETURN-CODE > 4
//NAME IF (STEP10.RC GT 4) THEN
To Test if RETURN-CODE from the
Job Step STEP10 > 4
23

24. IF/THEN/ELSE/ENDIF : Example
24

25. SET Statement
 Assign initial values to symbolic parameters
 Change or Nullify the values of symbolic parameter
 Syntax:
//[NAME] SET symbolic-parameter=values
 If there are more than one parameter, separate them by comma
 Example:
//SP1 SET PARM1=OLD,PARM2=22201
 Parameter values containing special character enclosed by apostrophes
 Example:
//SP3 SET PARM1=‘2004-10-13’
25

26. INCLUDE Statement
 Identify the member of a partitioned dataset containing the JCL statement
 Syntax:
//[NAME] INCLUDE MEMBER=name
 INCLUDE group cannot contain
 JOB Statement
 PROC and PEND statement
 JCLLIB statement
 JES2 and JES3 statement
 DD * and DD DATA statement
26

27. NULL STATEMENT
Indicates End of Job
27

28. Summary
 What is JCL ?
 Purpose of JCL
 Structure of JCL - Examples
 Coding Basics of JCL Statements
 JCL Statements – Essential and Optional
28

29. JOB Statement
Session 2
29

30. Session Coverage
 Purpose of JOB Statement
 Coding Syntax of JOB statements
 Positional and Keyword parameters in a Job Statement
 Examples
30

31. Purpose of JOB Statement
 Identifies a job to the OS using a job
name
 Indicates which user is responsible
for the job
 Tells the system how to process the
job
31

32. JOB Statement - Syntax
•
Operation Field Comment Field
//Jobname JOB < parameters>..<comments>
Name Field Operand Field
(Job Name)
32

33. JOB Statement - Name field
//TRGR02Y JOB .......
Job name is TRGR02Y
Job name is @TEST
//@TEST JOB .......
33

34. JOB Statement - Operation field
//MYJOB JOB ...
JOB in Operation Field
specifies it as Job statement
//JOB1 JOB ...
34

35. Parameter Field
• //JOBNAME JOB <Parameters>
• The following list shows the parameters on Job statement
• ACCT-PARAMETER
• PROGRAMMER NAME
Positional Parameters
•
• CLASS COND
• PRTY NOTIFY
• MSGCLASS RESTART
Keyword
• MSGLEVEL ADDRSPC
• REGION TIME
Parameters
•
35

36. Positional Parameters
 Job Statement can contain two positional parameters
 First parameter should contain Accounting Information and the second parameter
should contain the Programmer’s name
 These two parameters are optional, but installation may define them as
mandatory.
36

37. Positional Parameters - Accounting
Information
 //JOB1 JOB (XYZ,TRG,3,DB2,123) ...........
Accounting information
 //JOB2 JOB (XYZ,DHC,1,DTX99,TRGG01) ......
37

38. Accounting Information in Real world
 Five Fields - all are mandatory
 Field1 - Group or Project
 Field2 - Sub-Group or module or Project
 Field3 - User-id
 Field4 - Location (here type D2 or D1)
 Field5 - Type of Job (Give DT99X)
 Example for Training:
(TRG,TRG,TRGG01,D2,DT99X)
38

39. Positional Parameters - Programmer’s
Name
•
 //JOB1 JOB (XYZ,TRG,3,DB2,123),TRAINING.......
2nd positional parameter-
Accounting parameter programmer's name
 //JOB2 JOB (XYZ,DH,1,DTX99,TRGR01),’XYZ TRG’.
 //JOB3 JOB ,’Shane o’’Hara’.....
Programmer's name
parameter in quotes
No accounting Enclose programmer‘s name within
parameter apostrophe if it contains special character
39

40. Key Word Parameters
The Job Statement (or Job Card) can contain the following Keyword
parameters
 CLASS  PRTY
 TIME  ADDRSPC
 REGION  MSGCLASS
 MSGLEVEL  NOTIFY
 COND  RESTART
 TYPRUN
40

41. Keyword Parameters - CLASS
 Syntax:
 CLASS=<job class>
 Examples:
 //JOB1 JOB ACCT1,CLASS=A..
 //JOB2 JOB ACCT1,CLASS=B.... JOB1 IS ASSIGNED TO CLASS A
 //JOB3 JOB ACCT1,CLASS=C.... JOB2 IS ASSIGNED TO CLASS B
 //JOB4 JOB ACCT1,CLASS=D....
JOB3 IS ASSIGNED TO CLASS C
JOB4 IS ASSIGNED TO CLASS D
41

42. Class Definitions in Real world
Installation
 Class A -- 2 sec
 Class B -- 7 sec
 Class C -- 19 sec
 Class D -- 46 sec
 Class E -- 5 mins
 Class H -- Held Class
 Class T -- 5 mins (for tapes only)
 Class R -- 5 mins. (cartridges only)
 Time specified are CPU time
42

43. Keyword Parameters - TIME
 Syntax:
Allows this job to use 2 min
 TIME=([minutes][,seconds]) 30 sec of CPU time
 Examples:
 //JOB1 JOB ACCT1,CLASS=E,TIME=(2,30)....
Allows this job to use
30 sec of CPU time
 //JOB2 JOB ACCT1,CLASS=E,TIME=(,30)...
 //JOB3 JOB ACCT1,CLASS=E,TIME=2.... Allows this job to use
2 mins of CPU time
43

44. Keyword Parameters – TIME (Contd.)
 Syntax:
 TIME=([1440]| [NOLIMIT] | [MAXIMUM])
 Examples:
 //JOB4 JOB ACCT1,CLASS=E,TIME=1440....
 //JOB5 JOB ACCT1,CLASS=E,TIME=NOLIMIT.... These jobs can use the processor
for unlimited amount of time
 //JOB6 JOB ACCT1,CLASS=E,TIME=MAXIMUM....
This job can run for maximum amount
of time that is 357912 minutes.
44

45. Keyword Parameters - PRTY
 To assign the selection priority to the JOB
 Syntax:
 PRTY=(number)
 Examples:
 //JOB4 JOB ACCT1,CLASS=E,PRTY=12...
45

46. Keyword Parameters - REGION
 Syntax:
 REGION={valueK | valueM}
 Examples:
 //JOB1 JOB ACT1,CLASS=A,ADDRSPC=REAL,REGION=200K.
Specifies 200 kilo bytes of
 //JOB2 JOB ACT1,’TRG’,CLASS=A,REGION=20M. central storage is required for
this job(JOB1)
 Specifies 20 mega bytes of
virtual storage is required for
 this job(JOB2)
46

47. Keyword Parameters - ADDRSPC
 Syntax:
ADDRSPC={REAL | VIRT}
 Examples:
//JOB1 JOB ACT1,CLASS=A,ADDRSPC=REAL,REGION=20K
Non pageable central storage of 20k
is required for this job(JOB1)
//JOB1 JOB ACT1,CLASS=A,ADDRSPC=VIRT,REGION=20K
Pageable virtual storage of 20k
is required for this job(JOB1)
47

48. Keyword Parameters - MSGCLASS
 Syntax:
MSGCLASS=<class>
 Examples:
//JOB1 JOB (XYZ,TRG,3,,123),’TRG GROUP’,
// CLASS=B,MSGCLASS=X...
//JOB2 JOB (XYZ,TRG,3,,123),’TRG GROUP’,
// CLASS=B,MSGCLASS=A...
48

49. Keyword Parameters - MSGLEVEL
 Details in the listing of Joblog can be controlled, using MSGLEVEL
parameter
 Syntax:
MSGLEVEL=([statements][,messages])
 Job log contains the following information :
 JCL Statements
 Procedure Statements for any procedure job step calls
 Messages about Job control statements, allocation of devices and
volumes, execution and termination of job steps and disposition of
datasets
49

50. Keyword Parameters - MSGLEVEL
• Statements - Controls the listing of JCL statements in Job log
• 0 - The system prints the JOB statement, comments
• and all statements up to the first EXEC
• statement
• 1 – The system prints all the JCL statements, control
• statements, Procedure statements and values
• assigned to symbolic parameter’s
• 2 – The system prints all the JCL statements and control
statements
50

51. Keyword Parameters - MSGLEVEL
• Messages - To control the listing of JCL and JES
• messages in Job log
• 0 – The system prints only the JCL messages
• 1 – The system prints, JCL, operator and SMS
• messages
51

52. Statements sub-parameter -
MSGLEVEL
 MSGLEVEL=([statements][,messages])
Only job statement
is printed for job(job1)
 //JOB1 JOB AC1,MSGCLASS=X,MSGLEVEL=(0,1)..

NO parentheses ??
 //JOB2 JOB AC1,MSGCLASS=X,MSGLEVEL=2..
Both Statements and
Messages are printed
 //JOB3 JOB AC1,MSGCLASS=X,MSGLEVEL=(1,1)
52

53. Messages sub-parameter - MSGLEVEL
 MSGLEVEL=([statements][,messages]) Only JCL messages are
printed for job(job1)
 //JOB1 JOB AC1,MSGCLASS=X,MSGLEVEL=(0,0)..

No value for messages
Sub-parameter. Takes
 //JOB2 JOB ACC1,MSGCLASS=X,MSGLEVEL=2.. default.
All messages are printed
 //JOB3 JOB AC1,MSGCLASS=X,MSGLEVEL=(,1)
53

54. Keyword Parameters - NOTIFY
 Syntax:
 NOTIFY=<user-id> or
 NOTIFY=<nodeid.userid> or
 NOTIFY=<&SYSUID> User-id TRGG01 is notified
 Examples: after completion of this job
 //JOB1 JOB ACCT1,CLASS=A,NOTIFY=TRGG01..
 //JOB2 JOB ACCT1,NOTIFY=XYZMN03.TRGG02..
User-id TRGG02 at XYZMN03 is
Notified after completion of this job
54

55. Keyword Parameters - TYPRUN
 Syntax:
 TYPRUN={HOLD|SCAN}
Checks job’s JCL for syntax errors.
 Examples: Job is not submitted for execution
//JOB1 JOB ACCT1,MSGCLASS=X,TYPRUN=SCAN..
//JOB2 JOB ACCT1,MSGCLASS=X,TYPRUN=HOLD..
This job waits for execution until
operator releases it for execution
55

56. Keyword Parameter - RESTART
 Syntax:
 RESTART={* } Restart job at first job step itself
 {stepname}
 {stepname.procstepname}
 Stepname:
 indicates the job step from which to restart the job
 Stepname.procstepname:
 stepname refers to the EXEC statement of the jobstep that calls the
procedure.
 Procstepname refers to the EXEC statement of the procedure step.
 If the stepname refers to the EXEC statement in a procedure then
procedure name is also specified.
56

57. Keyword parameter - RESTART
 Example:
//JOB1 JOB ACCT1,MSGCLASS=X,RESTART=COUNT..
Restart from step
COUNT
//JOB1 JOB CCT1,MSGCLASS=X,RESTART=PROC1.COUNT..
Restart from step
COUNT in procedure
step PROC1
57

58. JOB Statement Examples
 Example 1 :
//TRGG02X JOB (TRG,GEN,TRGG02,AA,DT99X),’TRG’,
// CLASS=B,MSGCLASS=X,NOTIFY=TRGG02
 Example 2 :
//GEMT01XX JOB (GEM,CIC,GEMT01,D2,DT99X),
// ‘GEM-PROJ’,CLASS=C,MSGLEVEL=(1,1),
// MSGCLASS=X,NOTIFY=GEMT01
58

59. Summary
 The purpose of the JOB statement
 Coding Syntax of JOB statement
 Various options for the Positional and keyword parameters
 Examples of JOB statement
59

60. EXEC Statement
Session 3
60

61. Session Coverage
 Purpose of Exec Statement
 Coding Syntax of Exec statements
 Positional and Keyword parameters in an Exec Statement
 Examples
61

62. Purpose of Exec Statement
 Used to specify which program or procedure an individual job step
has to execute
 Tells system how to process the job step
62

63. Exec Statement: Example
OS
Processing parameters
Beginning of step
Parameters to program
JCL Program or Proc name
//JOB1 JOB AC1,
// CLASS=A
//ST1 EXEC PGM=P1,
// PARM=‘04/11/01’.
// REGION=800K
// ..... DD ..
//
63

64. EXEC Statement in JCL
• //JOB1 JOB .... • Beginning of JOB
• //ST1 EXEC PGM=P1 • Beginning of step ST1
• //INPUT DD ..... • Statements that follow the Exec step ST1
• ............. •
• ............. •
• //ST2 EXEC PGM=P2 • Beginning of step ST2
• //INPUT DD ..... • Statements that follow the Exec step ST2
• .......... •
• // • End of Job
64

65. EXEC STATEMENT - Syntax
•
Operation Field Comment Field
//Stepname EXEC < parameters>.. <comments>
Name Field Parameters Field
65

66. Operation field
//MYSTEP EXEC ...
EXEC in Operation Field
specifies it as Exec statement
//STEP1 EXEC ...
66

67. Parameter Field
• //STEPNAME EXEC <Parameters>
• The following list shows the important parameters on Exec statement
• PROGRAM NAME
• (PGM= or PROC=)
Positional Parameter
• ACCT PARM
• ADDRSPC REGION
• TIME COND Keyword
Parameters
67

68. Positional Parameters
 Syntax:
PGM=<program name> OR
PROC=<procedure name> OR
<procedure name>
 Examples:
//STEP1 EXEC PGM=TEST
STEP1 executes program TEST
//STEP2 EXEC PROC=COMPILE
//STEP3 EXEC COMPILE
STEP2 & STEP3 invokes JCL
procedure COMPILE
68

69. Key Word Parameters
The EXEC statement can contain the following Keyword
parameters :
 ACCT •
 PARM
 ADDRSPC
 REGION
 TIME
 COND
69

70. Key word Parameters
 ACCT – provides accounting information for the job step
 ADDRSPC – prevents the step from being paged
 REGION - specifies the region size to allocate to a job step
 TIME - imposes a CPU time limit on the job step
70

71. Keyword Parameter - PARM
 Syntax:
PARM=(<sub parameter,[sub parameter]>)
 Examples: 25/01/01 is enclosed in
apostrophes because it contains
//STEP1 EXEC PGM=P1,PARM=TRGXYZ special characters ‘/’
//STEP2 EXEC PGM=P2,PARM=(10,’25/01/01’)
//STEP3 EXEC PGM=P3,PARM=‘25&&45’
Passes string 25&45
to program P3
71

72. Program Execution using PARM
JCL for executing program CP1 Cobol Program-CP1
• //JOB1 JOB ACCT1,TRG-GRP,
• // CLASS=B,NOTIFY=TRG???, • IDENTIFICATION DIVISION.
• // MSGCLASS=X • ENVIRONMENT DIVISION.
• //*This is to demonstrate • DATA DIVISION.
passing • WORKING STORAGE SECTION.
• //* parameters to program • LINKAGE SECTION.
thru JCL
• //STEP1 EXEC PGM=CP1, • 01 WS-DATE
• // PARM=‘31/03/01’ • 05 WS-CTRL-LEN PIC S9(4)
• // ...... ...... ..... COMP SYNC.
• // • 05 WS-CTRL-DATE X(8).
• //*This JCL executes • PROCEDURE DIVISION USING
program CP1 • WS-DATE.
72

73. Keyword Parameter - COND
 Syntax:
 COND=(code,Operator[,step name]) [,EVEN | ONLY]
 Examples:
//STP1 EXEC PGM=P1,COND=(0,NE)
If any preceding step
returns non zero return
code this step is bypassed
//STP2 EXEC PGM=P2,COND=(4,LT,STP1)
If step STP1 returns a code less
than or equal to 4 then this step is
executed else bypassed.
73

74. Keyword Parameter- COND
 Examples:
//STP1 EXEC PGM=P1,COND=EVEN
STP1 is executed even if a
preceding step abends
//STP2 EXEC PGM=P3,COND=((4,LE,STP1),ONLY)
STP2 is executed only if a preceding
step abends and return code of STP1
is less than 4
74

75. Relational Operators for COND
Rt r c d ( C f o jutc ml t dse
eun o eR ) r m s o pee t p
c n pr mt r
o d aa ee c ni u j bi
o tn e o f t r i aej bi
em t o f
n
C N =c d,G) R > c d
O D( o e T C =o e R <o e
Cc d
C N =c d,G) R >o e
O D( o e E Cc d R <c d
C=o e
C N =c d,E ) R ! c d
O D( o e Q C =o e R =o e
Cc d
C N =c d,L ) R < c d
O D( o e T C=o e R >o e
Cc d
C N =c d,L ) R <o e
O D( o e E Cc d R >c d
C=o e
C N =c d,N) R =o e
O D( o e E Cc d R! cd
C=o e
75

76. COND Parameter with Return Codes
• Job requiring special
Conditional execution
• ABOUT SELECT PROGRAM.
STP1 If Step • SELECT PROGRAM :
SELECT ABENDS • RETURNS - 0, IF AT LEAST ONE
RECORD IS SELECTED FOR
PROCESSING BY UPDATE
STP3 PROGRAM.
RC ABDMP END
• RETURNS - 12, IF NO RECORDS
12 ARE SELECTED FOR
0 PROCESSING BY UPDATE
If Records Exist
PROGRAM.
to Process
STP2 If Step
END
UPDATE ABENDS
76

77. COND Parameter with Return Codes
(Contd.)
 JCL for executing JOB described in the previous slide
//JOB1 JOB ACT1,TRG,CLASS=B,NOTIFY=TRGXXX
//STP1 EXEC PGM=SELECT
..... ...... DD STATEMENTS......
//STP2 EXEC PGM=UPDATE,COND=(12,LE,STP1)
..... ...... DD STATEMENTS......
//STP3 EXEC PGM=ABDMP,COND=ONLY
..... ...... DD STATEMENTS......
//
77

78. EXEC Statement Examples
• //TRGR02XX JOB (TRG,GEN,TRGR02,AA,DT99X),
• // ‘TRG’,CLASS=B,NOTIFY=TRGR02,MSGCLASS=X
• //ALLOC EXEC PGM=IEFBR14  This step allocates data sets
• .... ........ .......... .......... ....
• //COB EXEC PGM=IGYCRCTL,COND=(4,LT),  This step compiles a program
• // PARM=‘NUM,SOURCE,LIB,RES’,
• // REGION=2048K
• .... ........ .......... .......... ....
• //STPZ EXEC PGM=IEWL,PARM=‘REUS,LET’,  This step does link editing
• // COND=((4,LT,COB),(4,LT,ALLOC))
• .... ........ .......... .......... ....
• //
78

79. DD statement in EXEC cont....
• DD statement in EXEC statement is optional. DD statement is used
for specifying any input to the program or to specify where the output is to be
printed. If there is no input file and if there is no need of output, then we can
ignore the DD statement in EXEC part.
• System generation programs and the programs that are in system
library syslib and proclib can be executed by using EXEC statement without a
DD statement.
•Eg: //TRGRXX JOB 'MVS-MVS-U237011-Z9-DT08X',REGION=2096K
• //IKJACCNT EXEC IKJACCNT
• Once you login the mainframes region, the above job will start
executing automatically, this needs no DD statement.
79

80. Summary
 The purpose of the Exec statement
 Coding Syntax of Exec statement
 Various options for the Positional and keyword parameters
 Examples of Exec statement
80

81. DD Statement
Session 4
81

82. Session Coverage
 Purpose of DD Statement
 Coding Syntax of DD statements
 Temporary data sets
 DASD data sets
 Instream and SYSOUT data sets
 Examples
82

83. Purpose of DD Statement
•
OS
I/P & O/P data sets
Program location
Data set integrity Constraints
Input data
Resources required by job & processing program
DD Statements
83

84. DD Statement in JCL
• //JOB1 JOB ACT1,NOTIFY=TRGXXX
• //STEP1 EXEC PGM=P1
• //DD1 DD ...
• //DD2 DD ... DD statements for step STEP1
• ....
• //STEP2 EXEC PGM=P2
• //INDD DD ...
DD statements for step STEP2
• //DD2 DD ...
• ....
• //
84

85. DD Statement - Syntax
•
Operation Field Comment Field
//ddname DD < parameters>.. <comments>
Name Field Key word Parameters Field
(DD Name)
85

86. Keyword Parameters for DASD
datasets
• //ddname DD DSNAME=dataset name
• ,DISP=file’s status
• [ ,UNIT=device where the file exists ]
• [ ,VOL=SER=serial number of the volume ]
• [ ,SPACE=DASD space to be allocated ]
• [ ,DCB=Options for file’s data control block ]
86

87. DSNAME Parameter
 DSN Parameter specifies the Physical file name to be associated
with the DD Name referred by processing program or system.
DD Name Data set name in DSN
LOGICAL FILES NAME or PHYSICAL DATA SET
DD NAME - Referred by For the DD name referred
processing program or system by program or system
87

88. DSNAME Parameter
 Syntax:
DSN=<data set name> | <DSNAME(member)>| NULLFILE
 Dataset name can be :
 Qualified data set name
 Unqualified data set name
 NULLFILE
 PDS member name
 Temporary data set name
88

89. DSNAME Parameter : Examples
 Qualified data set name
//INFILE DD DSN=TRGXX.SRC.COBOL, .....
 Unqualified name as data set name
//DD1 DD DSNAME=TRGXX, ......
 Data set name for a Dummy Data set
//OUTFILE DD DSN=NULLFILE
 Member of a PDS as data set name(qualified data set name)
//INFILE DD DSN=TRGXX.SRC(MEM1) .....
89

90. Temporary Dataset
 Syntax:
DSN=&&<data set name>
 Dataset exists only during the execution of job. Usually called as Work files.
 Always deleted at the end of job
 Resides in Virtual Storage
 Compound DSN, joined by period not allowed in temporary dataset
90

91. Temporary Dataset : Example
91

92. DD Statements in relation with
programs
Cobol Program-CP1 JCL for executing program CP1
• IDENTIFICATION DIVISION. • //JOB1 JOB ACCT1,TRG-GRP,
• ENVIRONMENT DIVISION. • // CLASS=B,NOTIFY=TRG???,
• SELECT INPUT ASSIGN TO • //STEP1 EXEC PGM=CP1
• INDD. • //INDD DD ......
• SELECT OUTPUT ASSIGN TO • //OUTDD DD .......
• OUTDD. • //
• DATA DIVISION. • //*This is to demonstrate
• WORKING STORAGESECTION. relation between program
ddnames names to ddnames in
• PROCEDURE DIVISION.......
JCL.
...... .......
• //*This Run JCL for program
CP1
92

93. DISPOSITION Parameter - DISP
 Syntax:
DISP=<([current status][,normal termination DISP]
[,abnormal termination DISP])>
CURRENT NORMAL ABNORMAL
STATUS TERMINATION TERMINATION
NEW DELETE DELETE
OLD KEEP KEEP
SHR PASS CATLG
MOD CATLG UNCATLG
UNCATLG
93

94. DISP-Current Status : Examples
 Sharing the already existing data set.
//INFILE DD DSN=TRGXX.SRC(MEM1),DISP=SHR
 Exclusive control over already existing data set or writing to existing
data set. Existing records will be deleted.
//OUTFILE DD DSN=TRGXX.OUT,DISP=OLD
 Creating new data set.
//NEWDD DD DSN=TRGXX.NEW,DISP=NEW........
 For updating the existing data set in exclusive access mode and is
positioned at the end of the data, so the records may be added to
the end.
//DD1 DD DSN=TRGXX.TRN,DISP=MOD .....
94

95. DISP-Normal Termination : Examples
 Request to keep the data set on normal completion of step.
//INFILE DD DSN=TRGXX.SRC,DISP=(SHR.KEEP)
 To delete the data set on normal completion of step.
//OUTFILE DD DSN=TRGX.OUT,DISP=(OLD,DELETE)
 To catalog the data set on normal termination of step.
//NEWDD DD DSN=TRGX.NEW,DISP=(NEW,CATLG)
 To pass data set for use by subsequent step on normal termination
of step.
//DD1 DD DSN=TRGXX.TRN,DISP=(MOD,PASS)
95

96. DISP-Abnormal Termination : Examples
 To Keep the data set on abnormal completion of step.
//FILE1 DD DSN=TRGX.SRC,DISP=(SHR,PASS,KEEP)
 To Uncatalog the data set on abnormal completion of step.
//OUT1 DD DSN=TRGX.OUT,DISP=(OLD,,UNCATLG)
 To Catalog the data set on abnormal termination of step.
//NEWDD DD DSN=TRGX.NEW,DISP=(NEW,,CATLG)
 To Delete data set on abnormal termination of step.
//DD1 DD DSN=TRGXX.TRN,DISP=(,PASS,DELETE)
96

97. DISP Parameter - Defaults
• DISP coded on DD statement System Interpretation
• by default
• NO DISP PARAMETER DISP=(NEW,DELETE,DELETE)
• DISP=SHR DISP=(SHR,KEEP,KEEP)
• DISP=OLD DISP=(OLD,KEEP,KEEP)
• DISP=(,CATLG) DISP=(NEW,CATLG,CATLG)
• DISP=(OLD,,DELETE) DISP=(OLD,KEEP,DELETE)
• DISP=MOD (Treated as new) DISP=(MOD,DELETE,DELETE)
• DISP=MOD (Treated as old ) DISP=(MOD,KEEP,KEEP)
97

98. Parameters to Define Location of
Datasets
 UNIT
 Specifies the physical device where an existing dataset can be found or
where a new one can be found
 Specify only installation defined group of devices
 VOLUME
 Specifies the volume serial number of the particular tape or disk
involved
 Volume parameter is optional for new datasets
 For Cataloged datasets, Unit and Volume details need not be specified
98

99. UNIT Parameter
 Syntax:
UNIT=({[device-number][device-type] [group-name]}
{[,unit-count] [,P]} [,DEFER] )
or UNIT=AFF=ddname
 Examples:
//DD1 DD DSN=TRG1.U1,DISP=(NEW,KEEP),
// UNIT=3380 device-type
//DD2 DD DSN=TRG1.U,UNIT=SYSDA group name
99

100. UNIT Parameter
• //DD1 DD DSN=TRG1.U1,DISP=MOD,
• // UNIT=(3390,2) 2 devices are requested
• //DD2 DD DSN=TRG1.U,DISP=SHR,
• // UNIT=(,,DEFER) request to defer mounting
• //DD3 DD DSN=TRG1.AFF,DISP=OLD,
• // UNIT=AFF=DD1 requests same two devices as
• Step DD1
100

101. VOLUME Parameter
 Syntax:
VOLUME= ([PRIVATE] [,RETAIN]
[,vol-seq-number] [,vol-count]
[,{SER=(ser-no[,ser-o]..)} {REF=dsname}{REF=*.ddname}] )
101

102. VOLUME Parameter : Examples
• //IN DD DSN=TRG.V1,DISP=(,KEEP),SPACE=(TRK,10).
• // VOLUME=(PRIVATE,SER=WORK01)
• //OUT1 DD DSN=TRG.V2,DISP=SHR,
• // VOLUME=(,RETAIN,2)
• //OUT2 DD DSN=TRG.V3,DISP=NEW,SPACE=(1024,10),
• // VOLUME=(,RETAIN,,2,SER=(DEV01,DEV02))
102

103. VOLUME Parameter : Examples
• //IN DD DSN=TRG.V1,DISP=(,KEEP),SPACE=(TRK,10),
• // VOLUME=(,RETAIN,REF=TRG.V1)
• //OUT1 DD DSN=TRG.V2,DISP=SHR,
• // VOLUME=SER=DEV01
• //OUT2 DD DSN=TRG.V3,DISP=NEW,SPACE=(1024,10),
• // VOLUME=REF=*.OUT1
103

104. SPACE Parameter
 Syntax:
SPACE=
({TRK,}(prqty[,secqty][,dir])[,RLSE][,CONTIG][,ROUND])
{CYL,}
{blklen,}
Number of Units Special Processing Requests
Measurement
Unit
104

105. DCB Parameter
 DCB to define the Characteristics of individual data sets.
 Syntax:
DCB=(LRECL=nn[,BLKSIZE=yy][,RECFM=zz]
[,DSORG=mm])
nn - Logical Record Length
yy - Block size
zz - Record Format (F,FB,V,VB or U)
mm - Data Set Organization (PS or PO)
107

106. DCB Parameter : Examples
 DCB for new PS data set with fixed record length of 80 with
blocking(block contains 10 records)
//DD1 DD DSN=TRG.DCB,DISP=(NEW,CATLG),
// DCB=(LRECL=80,RECFM=FB,BLKSIZE=800),
// SPACE=(TRK,(5,5))
 DCB for new PDS data set with variable record length of 80 and no
blocking..
//DD1 DD DSN=TRG.DCB,DISP=(NEW,CATLG),
// DCB=(LRECL=80,RECFM=V,DSORG=PO),
// SPACE=(TRK,(5,5,2))
108

107. DD Statement for Instream data sets
 Syntax:
//ddname DD (*) [ ,DLM=xx ]
(DATA)
 Programs will treat the instream data as if it comes from a
sequential file of 80-Character records
 JES will copy the instream data to a spool volume
 Processing program can retrieve data from spool volume as it
executes
109

108. Instream data sets : Examples
 Example 1:
//INDATA DD *
Bh009189lk56
Akp0789mjirm
/*
 Example 2:
//INDATA DD DATA,DLM=@@
//STEP1 EXEC PGM=INPROG
//INPFIL DD SYSOUT=A
/*
110

109. DD Statement for SYSOUT data sets
 Syntax:
//ddname DD SYSOUT=x
 Example:
//SYSPRINT DD SYSOUT=A
 The SYSOUT parameter
 indicates that the data set should be processed by JES2/JES3
 Specifies the output class associated with the data set
111

110. DD Statements for Execution related
Data sets
 Specifying private program library
 JOBLIB
 STEPLIB
 Specifying dump data set
112

111. Specifying Private Program libraries
 Private libraries are specified to execute programs that do not
reside in the system libraries
 Job library applies to entire job
 Step libraries applies to only one step in a job
 If both JOBLIB and STEPLIB DD statements are coded, step library is
searched first
(Job library ignored for that job step)
113

112. JOBLIB : Example
• //MM01E JOB (36512),'LE MENENDEZ',NOTIFY=MM01
• //JOBLIB DD DSNAME=MMA.TEST.LOADLIB,DISP=SHR
• //STEP1 EXEC PGM=IEBGENER
• .
• .
• //STEP2 EXEC PGM=ORD2200A
• .
• .
114

113. STEPLIB : Example
• //MM01F JOB (36512),'LE MENENDEZ',NOTIFY=MM01
• //STEP1 EXEC PGM=IEBGENER
• .
• .
• //STEP2 EXEC PGM=ORD2200A
• //STEPLIB DD DSNAME=MM01.TEST.LOADLIB,DISP=SHR .
• .
• .
115

114. Specifying Dump data set
 Storage dump is the content of the virtual storage used by the
program before the job terminates with error
 To obtain storage dump, code DD statement named
SYSUDUMP, SYSABEND, or SYSMDUMP
 Syntax:
//SYSDUMP DD SYSOUT=*
 If a job step ends normally, the dump DD statement is ignored
116

115. Summary
 The purpose of the DD statement
 Coding Syntax of DD statements for
 Temporary data sets
 DASD data sets
 Instream data sets
 SYSOUT data sets
 Dataset Attributes
 DD Statements to specify private library data sets and dump data
sets
117

116. In-Stream and Cataloged Procedures
•
• As you gain more experience in submitting jobs, you will
find that you often use the same set of job control statements
repeatedly with little or no change.
•
• To save time and prevent errors, you can prepare sets of
job control statements that you can execute again and again. You
can do this through the use of two types of procedures: in-stream
procedures and cataloged procedures.
118

117. In-Stream procedure
• An in-stream procedure is a named set of job control
statements in a job that can be re-executed within that job, simply
by invoking the name of the procedure.
• This enables you to execute the set of control
statements more than one time in the same job without having to
repeat the statements.
• The maximum number of in-stream procedures you can code in any
job is 15.
119

118. Example ..
• Job Control Statement Explanation
• //JOB1 JOB CT1492,'JIM MOSER' Starts job
• //PTEST PROC Starts in-stream procedure
• //PSTA EXEC PGM=CALC Identifies first step in procedure
• //DDA DD DSNAME=D.E.F,DISP=OLD Request 3 data sets for first procedure step
• //DDB DD DSNAME=DATA1,DISP=(MOD,PASS)
• //DDOUT DD SYSOUT=*
• //PSTB EXEC PGM=PRNT Identifies second step in procedure
• //DDC DD DSNAME=*.PSTA.DDB,DISP=OLD Request 2 data sets for second procedure step
• //DDREP DD SYSOUT=A
• // PEND Ends in-stream procedure
• //STEP1 EXEC PROC=PTEST First step in JOB1, executes procedure
• //PSTA.IN DD * Adds in-stream data to procedure step
• . PSTA
• (data)
• .
• /*
•
120

119. Cataloged Procedure
• A cataloged procedure, like an in-stream procedure, is a
named set of job control statements. However, these control
statements are placed, or cataloged, in a partitioned data set (PDS)
known as a procedure library. This enables a cataloged procedure
to be invoked by any job.
• Cataloged procedures can be placed in the system
procedure library SYS1.PROCLIB or in any user-specified procedure
library (for example JCLLIB).
121

120. Example...
• Job Control Statement Explanation
• //MYPROC PROC Starts cataloged procedure
• //MY1 EXEC PGM=WORK1 Identifies first step in procedure
• //MYDDA DD SYSOUT=A Request 2 data sets for first procedure step
//MYDDB DD SYSOUT=*
//MY2 EXEC PGM=TEXT5 Identifies second step in procedure
• //MYDDC DD DSNAME=F.G.H,DISP=OLD Request 2 data sets for second procedure
step
//MYDDE DD SYSOUT=*
// PEND Indicate end of procedure
• Job Control Statement Explanation
• //JOB2 JOB ,'JACKIE DIGIAN' Starts job
• //STEPA EXEC PROC=MYPROC First step in JOB2, executes procedure
• //MY2.MYDDC DD DISP=(OLD,DELETE) Modifies DD statement MYDDC in procedure
step MY2
122

121. Job Processing Overview
Session 5
123

122. Job Processing
•
Input Conversion
Errors
Phase Phase
No Yes
Output Execution
Phase Phase
Error Details
Phase
Purge End
Phase Job
124

123. JES (Job Entry Subsystem)
 Internal Readers JES2/JES3
handles the Input Processing
 JES will select from the
initiator, the highest priority
job classes to run
 Initiator allocates the
resources required for the
job
125

124. Conversion Processing
 Conversion processing
 assigns a job number to the job
 analyzes the JCL statements
 merges in any cataloged procedures which they reference
 converts the JCL into "internal text", which is meaningful to JES
and the MVS job scheduler
 checks for syntax errors
 invokes various user exits
 if no errors are found, the converter stores the internal text on
the "spool" dataset and adds the job to the input queue
126

125. Execution Processing
 JES2 keeps track of each job by
building a Job Queue Element
 On the Queue, job is selected by
 Is initiator available for this
job class
 If more than 1 class for the
initiator, then select in order
of class
 Is the priority of the job
highest in the queue for this
job class
 At the completion of the job, JES
places the job in output queue
127

126. Spooling
Simultaneous Peripheral Operations On Line
 Spool is a buffer that holds
O/P for printers and process
instructions as devices
become available
 As one task is waiting for
resource, the next one is
taken for execution
 All output to spooled devices
is first written to disk
 Spooled O/P is then stored
and scheduled until the
printer is available
128

127. Output/Print/Purge Processing
 JES2 processes SYSOUT data sets either when job ends or data set is
closed
 O/P datasets are written to Print files in JES2 SPOOL
 The Print Processors selects the job by priority within class and
print output
 Once job processing is completed, the access space released and
job number becomes available for a new job
129

128. Input-Conversion-Execution : Summary
•
Spool
JCL Input
Phase Input
Queue
Conversion Job
Proclib Phase Queue
Execution Output
Queue
Phase
130

129. Program Execution
Session 6
131

130. Fundamentals
 Modular programming:
 Aims to split a problem into small, manageable units of work
(modules).
 Source module:
 Program written in a symbolic language.
 Forms the input to a language translator.
 Object module:
 The output from a language translator.
 Forms the input to the linkage editor.
 An object module may, however, be directly executed via the Loader.
 Load module:
 The output from the linkage editor; it is in a readily executable
format.
132

131. Job Execution
133

132. Compile-Link-Edit
134

133. DD Names for compile-link-go
•
procedures
COBOL Compile Step DD names
• SYSIN - Source program input for the COBOL compiler.
• SYSLIB - The copy library or libraries.
• SYSLIN - Object module output.
• SYSPRINT- Print Data set
• Link-edit Step DD names
• SYSLIB - The subprogram library or libraries.
• SYSLIN - Object module input.
• SYSIN - Additional object module input.
• SYSLMOD - Load module output.
• Execute (run) step DD names
• SYSOUT - Output from DISPLAY statements.
• SYSDBOUT - Symbolic debugging output.
• SYSABEND/SYSUDUMP- Abnormal termination (or storage dump)
output.
135

134. Linkage-editor Parm Options
 LIST - lists the linkage-editor control statements
 MAP - produces a storage map showing the length and relative
locations of all control sections.
 XREF - includes MAP plus a cross-reference table of the load
module.
 AMODE - value specifies whether the program uses 24- or 31- or
64- bit addressing
 RMODE - value indicates where in Virtual Storage, the program
must be loaded (24 or ANY)
136

135. Sample Compilation Job steps
• //COMP EXEC PGM=IGYCRCTL,
• //
PARM='SOURCE,APOST,MAP,LIST,LIB,NOCMPR2,XREF,FDUMP'
• //*
• //STEPLIB DD DSNAME=IGY.V2R1M0.SIGYCOMP,DISP=SHR
• //SYSIN DD DSN=&SRCE(&MEMBER),DISP=SHR
• //*SYSLIB DD DSN=copy-book-dataset-name,DISP=SHR
• //SYSPRINT DD SYSOUT=*
• //SYSLIN DD DSN=&&LOADSET,DISP=(NEW,PASS),
• // SPACE=(10,(25,5),,,ROUND),UNIT=3390
• //SYSUT1 DD UNIT=VIO,SPACE=(CYL,(1,1))
• //*
137

136. Sample Link Edit Job steps
 Example on multiple load module processing
//LKED EXEC PGM=IEWL,
// PARM='AMODE=31,RMODE=ANY,TEST,LIST,
// XREF,LET,MAP',REGION=512K
//SYSLIB DD DSNAME=CEE.SCEELKED,DISP=SHR
// DD DSNAME=CEE.SCEERUN,DISP=SHR
//LIB1 DD DSN=TRG1T.TEST.DSN1,DISP=SHR
//LIB2 DD DSN=TRG1T.TEST.DSN2,DISP=SHR
//SYSLMOD DD DSN=TRG1T.TEST.LOAD,DISP=SHR
//SYSUT1 DD SPACE=(1024,(50,50)),UNIT=VIO
//SYSPRINT DD SYSOUT=*
//SYSLIN DD DSN=&&LOADSET,DISP=(OLD,DELETE)
// DD DDNAME=SYSIN
//SYSIN DD *
NAME LOAD1(R)
INCLUDE LIB1(MEM1,MEM2,MEM3)
NAME LOAD2
/*
138

137. Sample Run Job
• //STEP1 EXEC PGM=TEST
•
• //STEPLIB DD DSN=TRG1T.COBOL.LOAD,DISP=SHR
• //DTXN DD DSN=TRG1T.COBOL.PGM,DISP=(SHR,KEEP)
• //SYSOUT DD SYSOUT=*
• //SYSDBOUT DD SYSOUT=*
• //SYSABOUT DD SYSOUT=*
• //SYSIN DD DUMMY
139

138. Summary
 The Compilation-Linkedit and execution procedure
 DD Statements involved in Compile-Linkedit-Run steps
 Sample Compilation and Linkedit jobs
 Sample Run JCL
140

139. References
 z/OS V1R3.0 MVS JCL Reference - Redbook
 z/OS V1R2.0 MVS JCL User's Guide – Redbook
 Murach’s Os/390 and z/OS JCL by Raul Menendez and Doug Lowe
141

140. THANK YOU
142