Dynamic JCL Generation

When defining a job within a network, a user can specify that its JCL is to be generated dynamically either at job activation time or at job submission time.

Dynamic JCL generation is achieved using the Entire Operations MACRO facility, an extension of the Natural programming language. This facility consists of standard Natural statements and text strings (JCL frames). The text strings can contain Natural escape characters followed by variables that will be replaced by their current value during dynamic generation.

These current values will be taken from symbol tables (see the relevant section) which must contain the current values to be substituted. The symbol table hierarchy to be used can be determined in the Usable Symbol Tables window which opens when you choose PF7 (Symb) on the Network Addition/Modification or Job Definition screen. See also the sections Listing Usable Symbol Tables and Symbol Escape Characters in the User' Guide.

If any symbol specified in the dynamic JCL is not in the symbol table indicated for the job, the symbol is searched for at substitution time (either activation or execution) in the symbol table(s) belonging to owner SYSDBA. A user can define any number of entries in a single symbol table or any number of symbol tables.

Additionally, Entire Operations passes standard variables defined in the parameter section to the dynamically generated program, such as job owner, network name, current job name and original scheduling date. The same applies to Natural system variables such as *DATE, *TIME and *USER. As these parameters can be replaced in any part of the JCL, different JCL configurations can be generated depending on time, date, user ID etc.

For further information, see the sections Dynamic JCL Generation (JCL Location MAC) and Editing Macro Sources for Dynamic JCL Generation in the User's Guide.

Entire Operations provides dynamic JCL generation for all supported operating systems (z/OS, z/VSE, BS2000, UNIX and Windows) as shown in the following examples.


Example 1: Dynamic JCL in a z/OS Environment

The following is the symbol table specified for the MACRO program:

Symbol Name Current Value
STEPLIB SN.SYSF.SOURCE
CLASS G

The variable from the parameter section is assumed to have the following value:

P-OWNER NET1

The system variables are assumed to have the following values:

*TPSYS COMPLETE
*DEVICE BATCH
*INIT-USER SN

The following is a Natural MACRO program including a parameter section and JCL with the Natural escape character (#) followed by variable names from the symbol table:

# DEFINE DATA PARAMETER USING NOPXPL-A
# LOCAL /* MUST BE CODED
# END-DEFINE
//SNMAC4 JOB ,#P-OWNER,MSGCLASS=X,CLASS=#CLASS //STEP01 EXEC
PGM=NOPCONTI,PARM='C0004' //STEPLIB  DD DISP=SHR,DSN=#STEPLIB
//* DEVICE: *DEVICE, INIT-USER: *INIT-USER //* TPSYS: *TPSYS
# IF CLASS = 'G'
//* THE MSGCLASS IS REALLY 'G'
# ELSE
//* ANOTHER MSG-CLASS FOUND
# END-IF
//*

The resulting dynamically generated JCL will be:

//SNMAC4 JOB ,NET1,MSGCLASS=X,CLASS=G
//STEP01 EXEC PGM=NOPCONTI,PARM='C0004' //STEPLIB  DD
DISP=SHR,DSN=SN.SYSF.SOURCE //* DEVICE: BATCH, INIT-USER: SN
//* TPSYS: COMPLETE
//* THE MSGCLASS IS REALLY 'G'
//*

Example 2: Dynamic JCL in a BS2000 Environment

The fields taken from the DB-INFO are assumed to have the following values after the FIND statement:

Field Value
NUCLEUS 055
LP1 1000
NU1 100
ACCOUNT EXAMPLE
NH1 4000
MSG FHL
VERSION 524

The variables taken from the parameter section have the following current values:

Variable Value
P-OWNER OS
P-JOB NUC055
P-EXECUTION-NODE 055

No symbol table was defined for this example job.

The following is the example JCL written using the Natural MACRO facility, including variables to be substituted from the DB-INFO view and the parameter section. Variables are preceded by the escape character (#):

# DEFINE DATA PARAMETER USING NOPXPL-A
#  1 L-JOB
# 1 REDEFINE L-JOB
# 2  L-JOB-A    (A3)
# 2  L-JOB-NUC  (N3)
# LOCAL   /* LOCAL VARIABLES START HERE
# 1 DB-INFO VIEW OF DB-INFO
# 2  NUCLEUS
# 2  LP1
# 2  NU1
# 2  ACCOUNT
# 2  NH1
# 2  MSG
# 2  VERSION    /* E.G. 524
# 1 LWP  (N7)
# 1 NUC  (N3)
# 1 SPOOL  (A10) INIT <'NOSPOOL'>
# END-DEFINE
# *
# MOVE P-JOB TO L-JOB-A
# MOVE P-EXECUTION-NODE TO NUC
# F1. FIND DB-INFO WITH NUCLEUS = NUC
/.NUC NUC LOGON #P-OWNER,#ACCOUNT
/OPTION MSG=#MSG
/REMARK
/REMARK  NUCLEUS #NUC
/REMARK
/SYSFILE  SYSLST = NUC NUC..LST.NUC
/SYSFILE  SYSDTA = SYSCMD
/FILE  ADA VERSION..MOD,LINK=DDLIB
/FILE  *DUMMY,LINK=DDLOG
/FILE  *DUMMY,LINK=DDSIBA
/FILE  ADA NUC..ASSO,LINK=DDASSOR1,SHARUPD=YES
/FILE  ADA NUC..DATA,LINK=DDDATAR1,SHARUPD=YES
/FILE  ADA NUC..WORK,LINK=DDWORKR1,SHARUPD=YES
/EXEC  (ADARUN,ADA VERSION..MOD)
# COMPUTE LWP = F1.LP1 * (F1.NU1 + 100)
ADARUN PROG=ADANUC,LP=F1.LP1,LU=65535,LWP=#LWP ADARUN
DB=#NUC,NU=#NU1,NC=20,TT=600,TNAE=1800 ADARUN NH= NH1
/SYSFILE  SYSLST = (PRIMARY)
/SYSFILE  SYSDTA = (PRIMARY)
/SYSFILE  SYSOUT = (PRIMARY)
/LOGOFF  SPOOL
# END-FIND

The resulting dynamically generated JCL will be:

/.NUC055 LOGON OS,EXAMPLE
/OPTION MSG=FHL
/REMARK
/REMARK  NUCLEUS 055
/REMARK
/SYSFILE  SYSLST = NUC055.LST.NUC
/SYSFILE  SYSDTA = SYSCMD
/FILE ADA524.MOD,LINK=DDLIB
/FILE *DUMMY,LINK=DDLOG
/FILE *DUMMY,LINK=DDSIBA
/FILE ADA055.ASSO,LINK=DDASSOR1,SHARUPD=YES
/FILE ADA055.DATA,LINK=DDDATAR1,SHARUPD=YES
/FILE ADA055.WORK,LINK=DDWORKR1,SHARUPD=YES
/EXEC (ADARUN,ADA524.MOD)
ADARUN PROG=ADANUC,LP=1000,LU=65535,LWP=200000 ADARUN
DB=055,NU=100,NC=20,TT=600,TNAE=1800 ADARUN NH=4000
/SYSFILE  SYSLST = (PRIMARY)
/SYSFILE  SYSDTA = (PRIMARY)
/SYSFILE  SYSOUT = (PRIMARY)
/LOGOFF NOSPOOL

Note:
Any JCL generated at activation time using the MACRO language can be modified by the user until the job is actually submitted. Of course this modification is valid only for the current network run.

Example 3: Dynamic JCL in a UNIX Environment

The following example illustrates dynamic symbol replacement within a Bourne shell script (escape character §):

#
# Bourne shell script for checking the number of users
# entered in /etc/passwd.
# If more than §USER-LIMIT entries appear,
# the script will be ended with exit 1.
#
#!/bin/sh
set -x
USER_COUNT='wc -l < /etc/passwd'
echo Number of users on node 'hostname' : $USER_COUNT
if test $USER_COUNT -gt §USER-LIMIT
then
    echo USER_COUNT_WARN
    exit 1
else
    echo USER_COUNT_OK
fi

The symbol table to be used should appear as follows:

Symbol Name Current Value
USER-LIMIT 100

The result is the following executable shell script:

#
# Bourne shell script for checking the number of users
# entered in /etc/passwd.
# If more than 100 entries appear,
# the script will be ended with exit 1.
#
#!/bin/sh
set -x
USER_COUNT='wc -l < /etc/passwd'
echo Number of users on node 'hostname' : $USER_COUNT
if test $USER_COUNT -gt 100
then
    echo USER_COUNT_WARN
    exit 1
else
    echo USER_COUNT_OK
fi

Note:
Any JCL generated at activation time using the Natural MACRO language can be modified by the user until the job is actually submitted. Of course this modification is valid only for the current network run.