COBOL

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modernAIze supports COBOL as an application estate source platform. Collect the programs that implement the selected business operation and the shared source they use. Copybooks supply record layouts or reusable definitions; called programs supply behavior that is not contained in the caller.

Inputs to prepare

COBOL source in .cob, .cbl, or .pco files and copybooks in .cpy files. Extensionless source members and copybooks are also supported.

Native assets and what to collect

Asset	Material to supply	What it contributes
Program	`.cob`, `.cbl`, `.pco`, or an extensionless source member	Data declarations, procedure logic, branches, calls, and file operations
Copybook	`.cpy` or an extensionless member	Shared record layouts or included source
Called subprogram	Its source member	Behavior behind a CALL rather than just its interface
Embedded database logic	The corresponding source, including `.pco` where used	Database interactions within the program
Runtime context	Approved notes on file assignments and invocation parameters	Interpretation of external bindings not established by source alone

Source members and compiled load modules are different artifacts. The analysis requires readable program source and relevant copybooks. A job-control file can provide useful execution context, but it is not a replacement for the COBOL source accepted by this project platform.

How to collect the inputs

Obtain program and copybook members from the controlled source repository or export them from the source libraries using the team’s normal mainframe tooling. Keep member names, source formatting, and relevant directory context intact. This collection route does not require a separate modernAIze extractor.

Include the intended version of shared copybooks and called programs. Check the readability of the exported text; binary executables or a listing with damaged characters cannot substitute for the source that defines the behavior.

Prepare the source

Choose the entry program or business operation and identify its source revision.
Collect its source, the copybooks it includes, and the relevant called programs.
Preserve member names and directory context; include the intended version of shared definitions.
Record external calls, file assignments, and execution context that remain outside the supplied source.

Investigate the analysis

Begin with the program’s control flow. Follow calls and performed routines, inspect the conditions that select branches, and relate file or database operations to the record layouts. Review input and output structures alongside the behavior that changes them.

Start with Briefing for the system-level explanation, then use the appropriate Landscape view and available Detail links to investigate the relevant processing. Keep the question tied to the supplied source revision.

Example review question

The following example is synthetic.

In an order-processing example, the entry program reads an order, validates it, calls a pricing program, and writes the result. The assessment needs the order copybook and the called pricing program to explain both the record contract and the price calculation.

Verify the scope

Confirm that the expected programs and shared definitions are represented. Inspect unresolved includes or external calls before treating the operation as fully described. A visible call establishes a dependency; the callee source is needed to investigate the behavior behind that boundary.

For extensionless members in ZIP packages, avoid dots in directory names (for example, use SRC_V2/PROGRAM rather than SRC.V2/PROGRAM). Preserve a mapping to the original source paths and check the upload result for omissions.