Primes

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The primes program is purely for demonstration purposes, it would be nonsensical to generate primes and retrieve the dividers from a database. The subprograms are in fact objects, containing methods and data.

Program structure

The program consists of a main program and three subprograms. The main program primesmain.cbl is invoked by the command 'primesmain report'. The subprograms implementing the objects and methods are:

  • primesui, providing the user interface as a print file
  • primesgen, manages the proces of primes generation and reporting, it does the prime determination too.
  • primes

Only the primes program makes use of the PostgreSQL database and so a good demonstration of three tier design.

primesmain

The program source code file is available for download here: primesmain.cbl . When executed primesmain puts out the file primes.prt.
The program only needs a cobol compile process, which is as follows:

/usr/bin/cobc -x primesmain.cbl -T primesmain.out

This results in the executable program file primesmain and the compilation listing pgcobol.out.

primesgen

The program source code file is available for download here: primesgen.cbl . The program has to be compiled as a module or a subprogram, it cannot be executed directly.
The program only needs a cobol compile process, which is as follows:

/usr/bin/cobc -x primesgen.cbl -T primesgen.out

This results in the program module file primesgen.so and the compilation listing primesgen.out.

Sample database

The employee database is a very simple database, with one table containing three lines. The pg_dump file is in the link.

The cobc GNUCobol compilation

The command invoking the precompile process is as follows:

/usr/bin/cobc -x pgcobol.cbsql -l:libgixsql.so -T pgcobol.out

This results in the executable program file pgcobol and the compilation listing pgcobol.out.



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