CMS - External Files (JCL)

External Files (JCL)

The Mainframe Analyzer (for JCL) can handle programs (called by JCL Jobs) that call one or more external files. These files are declared in the DD cards that form part of the steps. They contain a DSN or DSNAME property. For each of these DD cards, the Mainframe Analyzer will create an object file (“JCL Data Set” type) sorted by an index whose path equals the DSN or DSNAME property.

How to identify which steps have declared file…

  • An ACCESS type link (with or without the R, W or E options) is created between the step and the file.

How to identify the actual file used by a program…

  • For a Cobol program, Mainframe Analyzer will search for the “File Link” or “Data Link” that corresponds with the ticket belonging to the DD card in which the file is declared. A PROTOTYPE link is then created between the file and the program’s “File Link” or “Data Link”.

What happens when the data set is an executable called by the step?

  • An ACCESS type link (with the E option) is created between the step and the file.
  • A PROTOTYPE type link is created between the file and the program that is being executed.

Links generated by the JCL Analyzer for external files

See the Mainframe Reference Guide for more information about link types created by the analyzer.

Link TypeLinked Objects
CallingCalled
ACCESSWRITEJCL StepJCL Data Set
READ
EXECUTE
PROTOTYPEJCL Data SetCobol File Link
JCL Data SetCobol Data Link
JCL Data SetCobol JCL Program

Concatenated Data Sets

In a step or a job, it is possible to link several data sets sequentially or by partition (PDSs or PDSEs). In order to concatenate them, the name of the DD card is only defined once.

Example:

//INPUT DD DSNAME=FGLIB,DISP=(OLD,PASS)//      DD DSNAME=GROUP2,DISP=SHR

In this code example, the Mainframe Analyzer will consider that the links to be generated on FGLIB and GROUP2 will depend on the configuration for the INPUT card.

See Also

JCL Advanced Configuration via XML file | Mainframe Reference Guide

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