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

Table Of Contents
Interoperating Between User Environments
Open System Services Porting Guide520573-006
4-2
Purpose of Interoperability
The ability of an application to use the application program interface (API) of either
the OSS or Guardian environment
The ability of one API to access or manipulate objects of both environments
The ability of utilities to access or manipulate objects of both environments
The primary objective of interoperability is to support and encourage the development
of new applications for the OSS environment and the porting of existing UNIX
applications from other platforms to the OSS environment. Another major objective is
the migration of Guardian applications to the OSS environment. All these applications
running in the OSS environment can take advantage of the parallelism, fault tolerance,
and scalability of a NonStop system.
Open System Services accomplishes interoperability between environments using
standard function calls and HP extensions to these calls and to the Guardian
procedures. Section 1, Introduction to Porting, discusses the relationships of the OSS
and Guardian environments to the NonStop operating system.
Figure 4-1 illustrates interoperability between the OSS and Guardian environments.
The line weight of the arrows represents the degree of availability and effectiveness of
operations within one environment and between environments. The thick, vertical
arrows signify the availability of more services, functions, procedures, utilities and so
on for one-environment operations. The thin arrows pointing to the objects signify that
fewer services are available for these operations. Whenever possible, stay within a
single environment when it makes sense to do so.
For example, it would not be efficient to select an OSS process to use a Guardian
application program interface (API) to access an OSS object; this operation would
involve additional, internal exchanges. The more direct route is to stay in the OSS
environment for this operation.