Pathmaker Programming Guide

The Structure of Pathmaker Custom Services and Servers
Creating Services and Servers
4–4 067868 Tandem Computers Incorporated
The Structure of
Pathmaker Custom
Services and Servers
This subsection describes the structure of a Pathmaker custom server and the services
it contains and explains which portions the Pathmaker product creates for you and
which portions of a server you are responsible for creating. When creating a custom
server using Pathmaker, follow these steps:
1. Add one or more custom services using Pathmaker screens or PMADL.
2. Generate SQL database access statements for single tables using Pathmaker
screens or PMADL (optional).
3. Write C or COBOL code for each custom service in special EDIT files called
Custom Source Files (formerly called Transaction Copy Libraries).
4. For C custom services, separately generate and compile each service using
Pathmaker screens or PMADL (optional).
5. Package services into servers using Pathmaker screens or PMADL. (Custom
COBOL services cannot be packaged together with custom C services.)
6. Generate and compile servers using Pathmaker screens or PMADL.
Custom COBOL85 Servers When the Pathmaker product generates a server, it creates a main program in
COBOL85 that contains Procedure Division code to handle the interprocess
communication (IPC) messages for all the services in the server and logic to pass
control to the appropriate service subprogram. (When a Pathmaker custom server is
generated, each service in it is included as a separate COBOL85 subprogram.)
The Pathmaker product generates the Identification, Environment, and Data Divisions
for this main program and some Working-Storage Section variables used for
controlling the program logic.
The list below summarizes which portions of a custom COBOL85 server the
Pathmaker product creates for you and which portions you are responsible for
creating.
What you do not need to code:
$RECEIVE handling
Overall server control logic
Enscribe FDs and file OPEN and CLOSE statements
IPC definitions
Some error handling in the server, including 88 levels for checking file conditions
and declaratives for all I/O operations
For NonStop SQL servers, the Pathmaker product also supplies some embedded
NonStop SQL code for:
SQL INVOKE statements to define NonStop SQL host variables (including
appropriate NULL and VARCHAR structures)
SQL INVOKE statements in interprocess communication (IPC) messages