GDSX Manual

Extended General Device Support (GDSX) Manual–134303
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About This Manual
This manual describes the operation of the Extended General Device Support (GDSX)
product. GDSX is used to help you develop either a back-end process for message
switching or a front-end process for implementation or modification of data
communications protocols or support of nonstandard terminal devices.
GDSX code contains the following:
•
A set of generic service routines that are supplied by Tandem to support
multithreaded, fault-tolerant processing.
•
User-written code for application-specific data communications requirements.
When the code supplied by Tandem and the user-supplied code are bound, the result is
an operational GDSX process. This operational GDSX process runs as an interface
between a business-oriented application program and either an input/output process
(IOP) or a message-switching process.
Who Should Use This Manual
This manual is written for people doing systems analysis, design, development,
operation, and/or support of GDSX applications. Because, for a given application, one
person may be doing any or all of these functions, headings in the manual refer to
analysis, design, development, operation, and support as roles or phases in the product
life cycle, rather than as job titles for different people.
With the exception of some system operators who may be concerned only with
operations of GDSX applications, readers are assumed to be experienced system
programmers who are experts in the following:
•
TAL programming
•
Guardian procedure calls
•
Transaction Management Facility (TMF)—a component of the NonStop Transaction
Manager/MP (NonStop TM/MP) product
•
Data communications, if their application is to include protocol conversion
Readers are also assumed to be familiar with the following:
•
Principles of multithreading
•
Principles of fault tolerance, if their application is to run as a process pair