QUICKSTART Conversion Facility (QCF)

The QUICKSTART Conversion Facility (QCF) is a series of modules which automatically convert existing COBOL/DB2 source programs to use QUICKSTART.QCF will typically perform 90% or more of the changes required for most application programs. In many instances, 100% of the changes will be performed. The current version of QCF operates upon COBOL programs using DB2 as the DBMS. For COBOL programs not using DB2, QCF will still perform all conversion work for sequential file activity. See QCF-limitations for conversion limitations.

QCF modifies source programs in a three step batch job. Step one reads the source program and expands all copybooks, producing an interim source file. The expansion process is necessary so that all included code can be examined for possible conversion. For example, a copybook may include File Definitions for sequential files.Since sequential files are managed by QUICKSTART, the FD statements will have to be removed, and the file layouts must be moved to the Working Storage Section.

The second step of QCF makes the source code modifications necessary to make the program QUICKSTART-ready. It takes the output file from the first step, and creates another source file containing the converted program. This step also produces a conversion report which lists conversion options and status messages.

The third step reads the converted source program from step two, notes any changes made to the copybooks, and writes them to a Partitioned Data Set (PDS) as separate members. The expanded copybooks are removed from the converted program, and the references to them are placed back in (i.e. COPY, INCLUDE statements). The converted program is then written to the same PDS as the copybooks. The conversion process does not overlay existing source code. All new programs and copybooks are written to a new PDS.

Provided that QCF is able to convert the entire program, the program is ready to be compiled, using the new copybooks. If QCF cannot make all the necessary changes,the conversion report will produce messages indicating which statements must be manually converted by the programmer.

It is important to note that QCF does not make a program restartable if the program is not structured into logical units of work. To achieve program restartability, programs must be structured into logical units of work, and must contain a COMMIT statement. Only then will the benefits of QCF be fully realized.

The following is a summary of the COBOL statements that QCF converts:

• Replacement of sequential file definitions (SELECTs and FDs) with QUICKSAM definitions (SAMn-...) in Working Storage. If the QSFD QCF option is chosen, this step is not done.
• Replacement of sequential file access verbs (OPENs, CLOSEs, READs, WRITEs) with QUICKSAM CALLs. If the QSFD option is chosen, READs/WRITEs are left alone, but OPENs and CLOSEs are replaced with the QSFD COPY statements.
• Insertion of Working Storage fields used by CKPT-RTN. All existing Working Storage fields are placed into the CKPT-SAVE-AREA.
• Insertion of PERFORMs of CKPT-RTN at the Procedure Division beginning, end,and in place of the EXEC SQL COMMIT statement.
• Insertion of CKPT-RTN Procedure at the end of the Procedure Division. A COPY or INCLUDE statement may be generated instead of actual insertion of the Procedure code.

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