GDSX Manual

About This Manual
Extended General Device Support (GDSX) Manual–134303
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Design and Development
Design and Development
Readers doing design and development might need to do the following tasks:
•
Learn the basic internal control flow of a simple GDSX application.
•
Determine what hardware and software would be necessary to use GDSX for an
application.
•
Identify guidelines and restrictions relevant to the design and development effort,
including those applying to space, memory pools, and procedure calls.
•
Understand the restrictions on communication between GDSX and other processes.
•
Understand the different levels of fault tolerance supported by GDSX.
•
Determine whether GDSX can be used to develop a particular application.
•
Configure GDSX to run converted or unconverted, and at a low PIN or a high PIN.
•
Run GDSX with different options and parameters, and change configuration
parameter values after creation time.
•
Compile, bind, and run example programs.
•
Use SCF to configure and manage GDSX objects, and to obtain statistical data on
GDSX operations.
•
Understand the typical environment of executing DEVICE^HANDLER tasks, as
well as the typical basic structure of DEVICE^HANDLER code.
•
Understand the purposes of the various control structures and how to access them.
•
Determine which user exits need to be developed for their application.
•
Code user exits, using the available TSCODE utilities and the pseudo procedures.
•
Interpret GDSX abend, trap, fault, EMS event, and configuration error messages.
•
Run a trace in GDSX.
References
See Section 1 for an overview of GDSX. Unless you are already very familiar with
GDSX, it will probably be helpful to do the tutorial in Sections 4 through 7. If your
application has or will have a DEVICE^HANDLER only, you need only Sections 4 and
5. If your DEVICE^HANDLER is or will be multithreaded, you might find Sections 6
and 7 helpful.
See Section 2 for prerequisites for development; alternatives to using GDSX; general
guidelines on design and development, including information on converting existing
applications; D-series features; instructions for coding, compiling, binding, and testing;
memory pool, calling, and space restrictions; basic internal control flow; fault tolerance;
file system errors; EMS filters; semaphores; linked lists; configuration parameters;
tracing; GDSX internals; and the USAMPLE example program. For information on
running and managing GDSX, see Section 3.