Guardian Application Conversion Guide

Appendix C System Compatibility
096047 Tandem Computers Incorporated C–1
This appendix describes the compatibility between processes on C-series and D-series
systems in a network. A typical network has C-series systems with all processes at low
PINs and D-series systems with low-PIN unconverted processes, low-PIN converted
processes, and high-PIN converted processes. Figure C-1 shows three systems in a
typical network.
Figure C-1. Network of C-Series and D-Series Systems
Low PINs
(0-255)
System \CENT
(C-Series System)
High PINs
(≥ 256)
Low PINs
(0-254)
System \WEST
(D-Series System)
System \EAST
(D-Series System)
Low PINs
(0-254)
Converted Process
Unconverted Process
High PINs
(≥ 256)
This appendix describes these compatibility issues for processes on C-series systems
and D-series systems in a network:
Identifying disks and devices using C-series and D-series file names
Identifying processes using C-series and D-series process identifiers
Ensuring compatibility between processes running on a C-series system and
descendent processes that run on a D-series system
Allowing opens by high-PIN requesters of an unconverted process
Communicating with a high-PIN process from an unconverted process
These issues do not consider Guardian file and process security or security provided
by the Safeguard subsystem. For more information about file and process security,
refer to the D-series Guardian Programmer's Guide.