Pathmaker Programming Guide

Requester Development Overview
Creating Requesters
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Coordinating IPC Messages
and Parameters
Two of the possible actions that can be associated with a particular function key in a
Pathmaker requester are:
SEND—To invoke a service
CALL—To call another requester
Before a fully functioning requester that has SENDs and CALLs can be completed, two
things must be done using Pathmaker screens:
Components of IPC request messages and reply messages between this requester
and each service it invokes must be coordinated. (This coordination is
automatically done by the Pathmaker product for IPC messages between DB
Requesters and standard services.)
Parameters between this requester and each requester it calls that is expecting
parameters must be coordinated.
Components and parameters being coordinated must have the same length and
compatible data types.
This coordination process is done using Pathmaker screens and can only be completed
for a requester if:
For each service that this requester invokes, the following have already been
specified, using Pathmaker screens:
The components of the IPC request message that the service expects to receive
The components of the IPC reply message that the service expects to return
For each requester that expects parameters and that is also called by this requester,
those parameters have already been specified using Pathmaker screens.
Note The Pathmaker product will automatically handle the coordination of a message or parameter component
if matching fields (same name, length, and compatible data type) are found for both the sender and
recipient of the message or parameter.
Generating and Compiling
SCREEN COBOL Source
Code
One of the most significant ways that the Pathmaker product speeds application
development is by generating efficient, bug-free requester source code in SCREEN
COBOL. The Pathmaker product generates this code from information in a project’s
catalog and from several other sources. Application developers initiate the generation
and compilation of a Pathmaker requester by filling in a screen that provides the
Pathmaker product with generation options and then pressing a function key. Figure
5-1 illustrates the generation and compilation of a requester using the Pathmaker
product.