OSI/MHS Gateway Programmatic Interface (GPI) Programming Guide

GPI Object Management
OSI/MHS Gateway Programmatic Interface (GPI) Programming Guide—424822-001
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Root Objects
When using GPI_OM_CREATE_ to create an object, you specify the desired object
class as a parameter. If the GPI_OM_CREATE_ initialize parameter is set to
OM-TRUE, the object is filled with default first-level attributes for that class.
In a sense, you can view the GPI_OM_CREATE_ procedure as creating a template for
an instance of a particular object class. If you wish to change the newly created
template, you can use GPI_OM_REMOVE_ and GPI_OM_INSERT_ to remove default
attributes and insert new ones, respectively.
Root Objects
Root objects are objects of the following three classes:
•
MH-C-MESSAGE
•
MH-C-PROBE
•
MH-C-REPORT
•
MH-C-P1-ENCODED-PDU
As the name “root” implies, these objects are the starting point for multilevel structures
that represent messages, probes, reports, or P1-encoded objects. As has been shown,
subobjects are inserted into the root object until a complete root object representation is
formed.
The GPI has some design rules related to root objects:
•
You must create a root object before creating any of its subobjects.
•
Only root objects can be transferred in and out of the gateway.
•
No more than 15 root objects can occupy client memory for each client process.
(This is true regardless of the number of sessions used by that process.)
Object Trees
Within GPI library memory space, the information for each object is stored in a data
table. The format of data within this table is called an object tree. Object trees are
Compaq’s internal representations of objects, and they do not relate to the XAPIA
specifications.
EDI-C-SERV-STRING-ADVICE
EDI-C-SYNTAX-ID
Note: The GPI supports only one OM class, OM-C-EXTERNAL (not listed).
Table 3-2. GPI Object Classes (page 2 of 2)
MH Classes IM Classes EDI Classes