GDSX (Extended General Device Support) Manual

Contents
Extended General Device Support (GDSX) Manual—529931-001
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2. Design and Development
Converted Application Features 2-3
Unconverted Application Features 2-3
GDSX D44 Features Supported 2-4
Coding and Testing Considerations 2-5
Coding the DEVICE^HANDLER 2-6
Coding the LINE^HANDLER 2-6
Debugging Your GDSX Application 2-7
Run-Time Environment 2-7
System Tasks 2-8
User Tasks 2-9
Overview of GDSX Processing 2-10
Calling Restrictions 2-12
Memory Management 2-13
Intertask Communication 2-14
Steps for Coding New Applications and Conversion 2-15
Coding New Applications 2-15
Conversion for Extended Features of D-Series Systems 2-16
Data Declarations 2-16
User Code Declarations 2-17
Space Usages and Limitations 2-19
User Data Segment 2-20
Extended Segment for Control Structures 2-21
Extended Segments for Trace Files 2-24
Memory Pools 2-24
Local Pools 2-25
Extended Memory Pools 2-26
Checkpointing Memory Pool Buffers 2-27
Pool Checking
2-28
Fault Tolerance
2-28
Level 0 Fault Tolerance 2-28
Level 1 Fault Tolerance 2-29
Level 2 Fault Tolerance 2-29
Fault-Tolerance Processing in GDSX Initialization 2-29
Checkpointing 2-31
Takeover Processing
2-34
Transaction Management Facility
2-37
TMF Configuration Parameter 2-37
Using the Pseudo Procedures 2-37
Linked Lists 2-38