HP ACMS for OpenVMS V5.0A

HP ACMS for OpenVMS, Version 5.0A SPD 82.40.02
• Task queuing
• Data dictionary
• Security
• OpenVMS Cluster environment and availability
Application Development Environment
ACMS uses a high-level, English-like definition lan-
guage that replaces system service calls for most TP
application functions. Using the ACMS Application Def-
inition Utility (ADU), a programmer can:
• Structure all application work into three basic steps:
— Exchange steps for terminal I/O processing
— Processing steps for database access and gen-
eral computation
— Block steps for performing work common to sev-
eral processing and exchange steps
• Control task execution and flow using conditional
statements such as IF THEN ... ELSE, WHILE DO,
SELECT FIRST, and CONTROL FIELD syntax in
conjunction with Boolean expressions.
•Define and implement subroutine transactions using
the CALL TASK syntax.
• Create menus and hierarchies of menus.
•Define resources used to execute transactions, such
as servers, workspaces, and audit trails.
• Start and end database recovery units.
ACMS also includes the ACMS Task Debugger to debug
ACMS definitions and servers.
Run-Time System
ACMS includes a complete run-time system for applica-
tion deployment. The ACMS Run-Time System consists
of eight specialized processes.
The following ACMS processes manage the work within
ACMS transactions:
• Command Process (CP) — Manages logins and in-
teraction between terminals and ACMS. CPs are
multithreaded (one CP process can handle menus
and forms I/O for many ACMS terminals simultane-
ously). The CP passes input data to the Applica-
tion Execution Controller (EXC) for processing by a
server.
• Application Execution Controller (EXC) — Controls
task execution for all the tasks in an application.
Each application has its own EXC process, which
starts up and controls the server processes needed
to handle processing work for tasks.
• Server Process (SP) — Carries out the high-level
programming language routines or DCL routines that
handle a task’s processing work and database or file
I/O. Programmers link their routines to the ACMS-
supplied main program to create customized servers
for database access, computation, and other func-
tions.
• Queued Task Initiator (QTI) — Removes task ele-
ments from a task queue and initiates their execution
in a specified application. Queued tasks are tasks
placed in a queue for later execution. Queued tasks
cannot collect terminal input data; otherwise they are
the same as any other ACMS task.
The ACMS processes that monitor and control the run-
time system are:
• ACMS Central Controller (ACC) — Acts as the cen-
tral control point for ACMS run-time systems. The
ACC starts and controls the Terminal Subsystem
Controller, the QTI, the EXC, and the audit trail log.
The ACC process must be started and running on
each computer system where ACMS applications are
used.
• Audit Trail Logger (ATL) — Writes information about
a running ACMS system to the audit trail log file. The
ATL keeps a record of when the ACMS system starts
and stops, when users log in, and when applications
and tasks start and stop.
• Terminal Subsystem Controller (TSC) — Creates and
controls the number of active Command Processes
(CPs) and assigns terminals to CPs. The TSC starts
and stops CPs as needed, and controls which termi-
nals can access ACMS.
• Software Event Logger (SWL) — Records all ACMS
internal software errors and event messages that oc-
cur during the execution of ACMS application pro-
grams.
Communication among these run-time processes can
occur on a single computer system, or between more
than one computer in a OpenVMS Cluster system or
DECnet network. For example, a Command Process
(CP) on one computer system can initiate a task within
an application on another computer system.
Application Management and Control
Once an application is developed, the user moves that
application into a production (real-use) environment.
ACMS provides support for ACMS applications used in
a production environment.
ACMS includes seven utilities for defining, monitoring
and modifying application management characteristics:
• ACMSGEN — Modifies and displays ACMS system
parameters.
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