HP 3000 Manuals

ALLBASE/SQL FORTRAN Application Programming Guide

Chapter 2  Using The ALLBASE/SQL FORTRAN Preprocessor 

ALLBASE/SQL FORTRAN application programs have the same stages of
development as any application program.  They originate as FORTRAN source
code files that are subsequently compiled with the FORTRAN compiler and
linked by the system linker to create an executable program file.  The
development of ALLBASE/SQL programs, however, requires that you
preprocess those portions of the program that contain SQL commands before 
compilation.

In the case illustrated in Figure 2-1 , the ALLBASE/SQL FORTRAN
program consists of one source file and one user include file.  The
preprocessor merges any user include file into the source program, and
preprocesses it.  The result is a modified source code file and a
preprocessor generated include file.  This preprocessor include file
contains all of the definitions of variables used by any FORTRAN
statements in the modified source code file.  These two files are then
compiled to produce an object code module, and linked to produce an
executable program file, in the same manner as any other FORTRAN program.


          Figure 2-1.  Developing a FORTRAN Program 

In other cases, the ALLBASE/SQL application program might consist of a
main program unit and one or more subprogram units in separate files.  In
these cases, only source files containing embedded SQL code need to be
preprocessed, as illustrated in Figure 2-2 .  However, each program
unit which contains SQL commands must be preprocessed and compiled before
the next program unit is preprocessed.  Separately preprocessed program
units that are not immediately compiled will write over each other's
preprocessor created include file and consequently create an error when
compiled.  You invoke the FORTRAN preprocessor and compiler as many times
as necessary to create the desired number of object code modules.


          Figure 2-2.  Developing a FORTRAN Program with Subprograms 

During preprocessing, the FORTRAN preprocessor actually accesses the same
DBEnvironment to be used by your main program or subprogram unit at
runtime.  The preprocessor stores a module in the DBEnvironment which is
executed at runtime.  The module is used at runtime to optimize and
validate DBEnvironment operations.

MPE/iX 5.0 Documentation