OSI/TS Management Programming Manual

Using SPI to Build Commands and Decode Responses
SPI Programming Considerations for OSI/TS
056786 Tandem Computers Incorporated 3–7
5. If you are resending a command to retrieve the next response message in a series,
call SSMOVE or SSMOVETKN to move the context token from the previous
response buffer into the command buffer.
6. Send the command message using the mechanism appropriate to your
programming language (for example, a WRITEREAD call in TAL).
The recommended buffer size in bytes for an OSI/TS command is a predefined value
with the name ZOS4-VAL-BUFLEN.
The OSI/TS subsystem does not support multiple commands in a single request
message. However, many of the OSI/TS commands accept multiple object names in
one command (as many as will fit in the buffer), so one command can affect a number
of objects. All objects named in a command must be of the same object type.
Object-name templates (wild-card names), an implicit way of specifying more than one
object in a command, can also be used with many commands.
The command buffers for the ADD and ALTER commands contain extensible
structured tokens.
Caution An extensible structured token that is to appear in a command should always be initialized using the SPI
procedure SSNULL. Doing this ensures that every field of the token is initialized to its null value. This is
important because an operation will be performed if a field contains a value other than its null value. For
example, in the ALTER command, if a field of the extensible structured token that describes the command
attributes contains a value other than its null value, that value is assigned to the attribute corresponding to
that field.
Using SSNULL is important even when your application assigns a value to every field of an extensible
structured token. Otherwise, the application will not work correctly later if it is compiled with a new version
of the definition files that add new fields to the token.
For the OSI/TS subsystem, only the LISTOBJECTS PROCESS command supports the
subordinate names option (ZCOM-TKN-SUB) to select subordinate objects. OSI/TS
does not support the summary-state selector token ZCOM-TKN-SEL-SUMSTATE.
In addition to ZCOM-TKN-OBJNAME, a few other tokens can appear more than once
in an OSI/TS command. These tokens are identified in the command descriptions in
Section 5.
Discontinuing a Command
in Progress
In commands operating on multiple objects, OSI/TS supports the use of the token
ZSPI-TKN-ALLOW-TYPE. This token allows an application to specify whether or not
OSI/TS should continue immediately to the next object if it failed on the current one.
If no value is specified for this token, OSI/TS continues to the next object only if no
errors or warnings occurred on the current one.
When the OSI/TS subsystem discontinues a command because of an error or warning,
it immediately sends a reply message to the application. The reply message contains a
context token. The application can choose either to resend the command including the
context token, causing OSI/TS to proceed to the next object, or to abandon the
command.