Open System Services Porting Guide (G06.24+, H06.03+)

Migrating Guardian Applications to the OSS
Environment
Open System Services Porting Guide—520573-006
8-4
Using OSS Functions in a Guardian Program
Using OSS Functions in a Guardian Program
More open features are available to a Guardian program with the use of OSS
functions, most of which can be called from a Guardian program. Refer to the API
interoperability tables in the Open System Services Programmer’s Guide for a
complete list of OSS functions that you can use to provide open features to Guardian
programs. Moreover, Guardian processes can take on some OSS attributes. Many of
these attributes can be manipulated only using OSS functions, which are noted in the
interoperability tables.
Communicating With OSS Programs
Another way to build more openness into your Guardian application is to support
communication capabilities with OSS programs by using any one of a number of IPC
mechanisms described in some detail in Section 6, OSS Porting Considerations. The
use of these communication mechanisms, along with the ability to create OSS
processes from the Guardian environment, give Guardian programs a significant
degree of interoperability with OSS programs.
Migrating a Guardian Program to the OSS Environment
The greatest degree of openness is provided by migrating the Guardian application to
run in the OSS environment. Before migrating your Guardian application to the OSS
environment, make sure that the Guardian functions used by your application either
are supported in the OSS environment or can be replaced by equivalent OSS
functions. If the functions used by the Guardian application cannot be used in the OSS
environment, they must be replaced with equivalent OSS functions in order to migrate
the application. If the Guardian application is started from the Guardian environment in
a manner not supported in the OSS environment, for example by using ASSIGNs,
DEFINEs, PARAMs, or system startup messages, this capability will need to be
provided by equivalent mechanisms in the OSS environment.
The features of a specific product used by your application might also impose
migration considerations. For example, migration of a SQL/MP or SQL/MX program to
the OSS environment requires considerations about security mechanisms, use of
filenames, recompiling the application, use of certain commands and statements, and
so forth. Refer to the SQL/MP Programming Manual for C or the SQL/MX
Programming Manual for C and COBOL for more information about SQL/MP or
SQL/MX applications in the OSS environment.
C Compiler Issues for Guardian Programs
The Guardian C or C++ programmer has typically used the TNS compiler tools
available in the Guardian environment to build TNS programs. To add open features
and performance to a Guardian TNS program, it is recommended that the programmer
use the native compilation tools described in the C/C++ Programmer’s Guide. The
differences between these two sets of tools are discussed in Section 2, The